Proposed Requirements for Designation of Reference and Equivalent Methods for PM<INF>2.5 and Ambient Air Quality Surveillance for Particulate Matter

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

[Federal Register: December 13, 1996 (Volume 61, Number 241)]
[Proposed Rules]
[Page 65779-65872]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]

ENVIRONMENTAL PROTECTION AGENCY
40 CFR Parts 53 and 58
RIN 2060-AH09
[AD-FRL-5659-2]

Proposed Requirements for Designation of Reference and Equivalent
Methods for PM<INF>2.5 and Ambient Air Quality Surveillance for
Particulate Matter

AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.

SUMMARY: The EPA proposes to revise 40 CFR part 58 to establish ambient
air quality monitoring requirements for PM<INF>2.5 (particles with an
aerodynamic diameter less than or equal to a nominal 2.5 micrometers)
as measured by a new reference method being proposed in Appendix L to
40 CFR part 50 or by an equivalent method designated in accordance with
requirements being proposed in 40 CFR part 53. In addition, this
document also proposes certain revisions to existing ambient air
quality monitoring requirements for PM<INF>10 (particles with an
aerodynamic diameter less than or equal to a nominal 10 micrometers).
The changes proposed in this document address among other things,
network design and siting, quality assurance and quality control, and
monitoring methodology. The document also indicates EPA's intent to
explore opportunities to coordinate and integrate the existing
visibility monitoring requirements with the ambient air quality
monitoring requirements for particulate matter being proposed today to
accommodate a better regional haze program and to reduce burdens and
achieve multiple monitoring objectives.

DATES: Comments must be submitted on or before February 18, 1997.

ADDRESSES: Comments should be submitted (in duplicate, if possible) to:
Air Docket (LE-131), U.S. Environmental Protection Agency, Attn. Docket
No. A-96-51, 401 M Street, SW, Washington, DC 20460. The docket may be
inspected between 8:00 a.m. and 5:30 p.m. on weekdays. A reasonable fee
may be charged for copying.

Public hearing: The EPA will announce in a separate Federal
Register document the date, time, and address of the public hearing on
this proposed decision.

FOR FURTHER INFORMATION CONTACT: Mr. Neil Frank (MD-14), Monitoring and
Quality Assurance Group, Emissions, Monitoring, and Analysis Division,
U.S. Environmental Protection Agency, Research Triangle Park, North
Carolina 27711, telephone (919) 541-5560.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Authority

II. Introduction

III. Discussion of Proposed Revisions to Part 53
A. Designation of Reference and Equivalent Methods
B. Quality Assurance

IV. Discussion of Proposed Revisions to Part 58
A. Section 58.1 Definitions

B. Section 58.13 Operating schedule
C. Section 58.14 Special purpose monitors
D. Section 58.15 PM<INF>2.5 NAAQS eligible monitors
E. Section 58.20 Air quality surveillance: plan content
F. Section 58.23 Monitoring network completion
G. Section 58.25 System modification
H. Section 58.26 Annual SLAMS summary report
I. Section 58.30 NAMS network establishment
J. Section 58.31 NAMS network description
K. Section 58.34 NAMS network completion
L. Section 58.35 NAMS data submittal
M. Appendix A--Quality Assurance Requirements for State and
Local Air Monitoring Stations (SLAMS)

N. Appendix B--Quality Assurance Requirements for Prevention of
Significant Deterioration (PSD) Air Monitoring
O. Appendix C--Ambient Air Quality Monitoring Methodology
P. Appendix D--Network Design for State and Local Air Monitoring
Stations (SLAMS), National Air Monitoring Stations (NAMS), and
Photochemical Assessment Monitoring Stations (PAMS)
Q. Appendix E--Probe and Monitoring Path Siting Criteria for
Ambient Air Quality Monitoring

R. Cost Estimates for New PM Networks
S. Reference

V. Administrative Requirements

A. Regulatory Impact Analysis

B. Reporting and Record keeping Requirements
C. Impact on Small Entities

D. Unfunded Mandates Reform Act of 1995

I. Authority

Sections 110, 301(a), and 319 of the Clean Air Act as amended 42
U.S.C. 7410, 7601(a), 7619.

II. Introduction

A. Proposed Revision to the Particulate Matter NAAQS

Elsewhere in today's Federal Register, EPA announced proposed
revisions to the national ambient air quality standards for particulate
matter. In that notice, EPA proposes to amend the current suite of
PM<INF>10 standards by adding new PM<INF>2.5 standards and by revising
the form of the current 24-hour PM<INF>10 standard. Specifically, the
EPA proposes to add two new primary PM<INF>2.5 standards set at 15
<greek-m>g/m3, annual mean, and 50 <greek-m>g/m3, 24-hour
average. The proposed new annual PM<INF>2.5 standard would be met when
the 3-year average of the annual arithmetic mean PM<INF>2.5
concentrations, spatially averaged across an area, is less than or
equal to 15 <greek-m>g/m3. The proposed new 24-hour PM<INF>2.5
standard would be met when the 3-year average of the 98th percentile of
24-hour PM<INF>2.5 concentrations at each monitor within an area is
less than or equal to 50.

The EPA also proposes to retain the current annual PM<INF>10
standard at the level of 50 <greek-m>g/m3, which would be met when
the 3-year average of the annual arithmetic PM<INF>10 concentrations at
each monitor within an area is less than or equal to 50 <greek-m>g/
m3. Further, EPA proposes to retain the current 24-hour PM<INF>10
standard at the level of 150 <greek-m>g/m3, but to revise the form
such that the standard would be met when the 3-year average of the 98th
percentile of the monitored concentrations at the highest monitor in an
area is less than or equal to 150 <greek-m>g/m3.
In the part 50 notice, EPA also proposed to revise the current
secondary standards by making them identical to the suite of proposed
primary standards. The suite of PM<INF>2.5 and PM<INF>10 standards, in
conjunction with the establishment of a regional haze program under
section 169A of the Clean Air Act (Act), are intended to protect
against PM-related welfare effects including soiling and materials
damage and visibility impairment.

As discussed in the part 50 notice, the proposed new PM<INF>2.5
standards are intended to protect against exposures to fine particulate
pollution, while the new PM<INF>10 standards are intended to protect
against coarse fraction particles as measured by PM<INF>10.
For PM<INF>2.5, the annual standard is intended to protect against
both long- and short-term exposures to fine particle pollution. Under
this approach, the PM<INF>2.5 24-hour standard would serve as a ``back
stop'' to provide additional protection against days with high
PM<INF>2.5 concentrations, localized ``hot spots,'' and risks arising
from seasonal emissions that would not be well controlled by a national
annual standard.

In specifying that the calculation of the annual arithmetic mean
for an area (for purposes of comparison to level of PM<INF>2.5 annual
standard) should be

[[Page 65781]]

accomplished by averaging the annual arithmetic means derived from
multiple, population-oriented monitoring sites, EPA took into account
several factors. As discussed in the part 50 notice, many of the
community-based epidemiologic studies examined in this review used
spatial averages, when multiple monitoring sites were available, to
characterize area-wide PM exposure levels and associated public health
risk. Even in those studies that used only one monitoring location, the
selected site was chosen to represent community-wide exposures, not the
highest value likely to be experienced within the community. Because
the annual PM<INF>2.5 standard would be intended to reduce aggregate
population risk from both long- and short-term exposures by lowering
the broad distribution of PM concentrations across the community, an
annual standard based on spatially averaged concentrations from several
population-oriented monitoring sites would better reflect areawide PM
exposure levels and associated health risks than would a standard based
on concentrations from a single monitor with the highest measured
values in the area. The spatial average approach is not appropriate for
PM<INF>10 because the spatial distribution of coarse particles is
different and tends to be more localized in its behavior.
Finally, under the policy approach presented in the part 50 notice,
the 24-hour PM<INF>2.5 standard would be intended to supplement a
spatially-averaged annual PM<INF>2.5 standard by providing protection
against peak 24-hour concentrations arising from situations that would
not be well-controlled by an annual standard. Accordingly, the 24-hour
PM<INF>2.5 standard would be based on the single population-oriented
monitoring site within a monitoring planning area with the highest
measured values.

In EPA's judgment, an annual PM<INF>2.5 standard expressed as a
spatial average, established in conjunction with a 24-hour standard
based on the monitoring site with the highest measured values, would
provide the most appropriate target for reducing area-wide population
exposure to fine particle pollution and would be most consistent with
the underlying epidemiologic data base. On the other hand, EPA is
mindful that adoption of spatial averaging for a PM<INF>2.5 standard
would add a degree of complexity to the monitoring siting requirements
and to the specification of those areas across which spatial averaging
should be permitted. This approach may also require larger monitoring
networks in some areas. By proposing a spatial averaging approach, the
part 50 notice recognizes that some monitoring planning areas may have
to be subdivided into smaller subareas to reflect gradients in particle
levels (e.g., upwind suburban sites, central city sites, downwind
sites) as well as topographical barriers or other factors that may
result in a monitoring planning area having several distinct air
quality regimes.

Recognizing the complexities that spatial averaging may introduce
into risk management programs and that unforeseen issues may arise from
public comment on the requirements presented in this notice, the part
50 notice also requests comment on the alternative of basing the
PM<INF>2.5 annual standard on the population-oriented monitoring site
within the monitoring planning area with the highest 3-year average
annual mean. The part 50 notice indicates, based on comments received,
that EPA may choose either of these two approaches for specifying the
form of the annual PM<INF>2.5 standard at the time of promulgation of
any revisions to the PM standards.

In the part 50 notice, EPA also solicits comments on alternative
levels of both annual and 24-hour PM<INF>2.5 primary standards and on
revoking the current 24-hour primary PM<INF>10 standard.

B. Air Quality Monitoring Requirements

Section 110(a)(2)(C) of the Act requires ambient air quality
monitoring for purposes of the State implementation plans (SIP's) and
for reporting data quality to EPA. Uniform criteria to be followed when
measuring air quality and provisions for daily air pollution index
reporting are required by section 319 of the Act. To satisfy these
requirements, on May 10, 1979 (44 FR 27558), EPA established 40 CFR
part 58 which provided detailed requirements for air quality
monitoring, data reporting, and surveillance for all of the pollutants
for which national ambient air quality standards have been established
(criteria pollutants). Provisions were promulgated subsequently for
particulate matter (PM<INF>10) on July 1, 1987 (52 FR 24740).
The intent of the air quality surveillance requirement being
proposed today is to establish a revised particulate matter monitoring
network that would produce air quality data for the purpose of
comparison to the proposed primary and secondary PM NAAQS and to
facilitate implementation of a possible new regional haze program. In
developing a new particulate matter monitoring network and associated
requirements, consideration has been given to the indicators, forms,
and levels of the proposed primary and secondary PM NAAQS. As a result,
nationwide monitoring would be performed for two indicators of PM:
PM<INF>2.5 and PM<INF>10. To be reflective of the basis for and the
specification of the forms of the proposed new annual and 24-hour
primary and secondary PM<INF>2.5 NAAQS, new monitoring network design
and siting requirements are being proposed. For purposes of comparison
to the proposed PM<INF>2.5 annual standard, such sites would be
population-oriented and be representative of community-wide exposure
levels. The siting criteria for monitors to be used for comparison to
the proposed 24-hour PM<INF>2.5 standard would also be populationoriented
but reflective of the highest measured values within the
community. To ensure PM data of the highest possible quality, new
requirements for quality assurance and designation of new PM<INF>2.5
reference or equivalent samplers are also described.
With respect to NAAQS comparisons and visibility protection in more
rural areas, the new network design and siting requirements would
encourage the placement of PM<INF>2.5 monitors outside population
centers with two purposes in mind: (1) To provide air quality data
necessary to facilitate implementation of the proposed NAAQS, and (2)
augmentation of the existing visibility fine particle monitoring
network. The coordination of these two monitoring objectives would
facilitate implementation of a regional haze program and lead to an
integrated monitoring program for fine particles.
The network design and siting requirements for the annual and 24-
hour PM<INF>10 NAAQS would continue to emphasize identification of
locations at maximum concentrations. The PM<INF>10 network itself,
however, would be revised because the proposed PM<INF>2.5 standards
would likely be the controlling standards in most situations.
The new network for PM<INF>10 would be derived from the existing
network of State and Local Air Monitoring Stations (SLAMS), National
Air Monitoring Stations (NAMS), and other monitors generically
classified as Special Purpose Monitors (SPM's) which include industrial
and special study monitors. Population-oriented NAMS will generally be
maintained, other key sampling locations in existing nonattainment
areas, and in areas whose concentrations are near the levels of the
proposed PM<INF>10 NAAQS will be continued. Currently approved
reference or equivalent PM<INF>10 samplers could continue to be
utilized. The revised network would ensure that analysis of national
trends in PM<INF>10 can

[[Page 65782]]

be continued, that air surveillance in areas with established PM
emission control programs can be maintained, and that the PM<INF>10
NAAQS will not be jeopardized by additional growth in PM<INF>10
emissions. PM<INF>10 sites should be collocated with new PM<INF>2.5
sites at key population-oriented monitoring stations so that better
definition of fine and coarse contributions to PM<INF>10 can be
determined to provide a better understanding of exposure, emission
controls, and atmospheric processes. PM<INF>10 sites not needed for
trends or for monitoring in areas with relatively high PM<INF>10
concentrations would likely be discontinued in a longer-term PM<INF>10
network. The sampling frequency at all PM<INF>10 sites would be reduced
to a minimum of once in 6 days, which would be sufficient to make
comparisons with proposed PM<INF>10 standards. The combination of fewer
PM<INF>10 sites and the reduction in required sampling frequency would
save significant resources that could be redirected to PM<INF>2.5
monitoring.

The new network for PM<INF>2.5 would consist of a ``core'' network
of population-oriented SLAMS monitors, ``core'' regional background and
regional transport SLAMS, a NAMS subset for long-term monitoring, other
SLAMS monitors, and supplementary network of SPM's. The core
population-oriented sites would be reflective of community-wide
exposure and would be required in all of the largest metropolitan areas
and must sample everyday. Frequent measurements are important to
understand episodic behavior of PM<INF>2.5, and to establish effective
emission control strategies to assure protection of the NAAQS. Many of
the new PM<INF>2.5 sites are expected to be located at existing
PM<INF>10 sites, and would be collocated with some PAMS sites.
Consistency with the proposed new PM<INF>2.5 NAAQS necessitates the
adoption of new concepts for identification and establishment of
monitoring stations for the PM<INF>2.5 ambient air monitoring network
as well as use of the data in relation to the proposed PM<INF>2.5
NAAQS. These concepts include: (1) The addition of specially coded
sites whose data would be used to compare to the levels of the annual
and 24-hour PM<INF>2.5 NAAQS, and (2) the inclusion of monitoring
planning areas and spatial averaging zones (SAZ) to correspond to the
population-oriented, spatial averaging approach. These concepts and
associated requirements are discussed in sections 58.15 and sections
2.8.1-2.8.3 of Appendix D below.

Although the major emphasis of the new PM networks is compliance
monitoring in support of the NAAQS, the network is also intended to
assist in reporting of data to the general public, especially during
air pollution episodes and to assist in the SIP planning process. To
these ends, additional monitoring and analysis requirements are
proposed concerning the location of nephelometers (or other continuous
particulate matter measuring devices) at some core monitoring sites and
the archiving of filters for possible subsequent analysis for subsets
of the PM<INF>2.5 SLAMS sites. Moreover, collection of meteorological
data at core SLAMS sites (including background and regional transport
sites) are suggested. The additional requirements should help to
further characterize the composition and trends in PM<INF>2.5 and
better understand the sources and processes leading to elevated
PM<INF>2.5 concentrations. Because these proposed revisions do not
specifically require the chemical analysis of collected PM<INF>2.5 or
PM<INF>10 filters, the Administrator would welcome comments on this
issue. In particular, comments are solicited on the need for
alternative PM<INF>2.5 monitoring methodologies and additional
monitoring requirements which might accompany the part 51
implementation rules to identify the causes of detected PM<INF>2.5
NAAQS violations and to assist in the development of PM<INF>2.5
emission control strategies.

While the proposed siting criteria and network designs are
appropriate for both the proposed revisions to the primary and
secondary NAAQS as a whole, additional consideration must be given to
air quality surveillance in more rural/remote areas to characterize
fine particle levels in order to protect against broader regional scale
visibility impairment. To achieve the appropriate level of air quality
surveillance in such areas, EPA believes it is important to coordinate
and integrate the background and transport monitoring sites specified
in this notice with the existing Interagency Monitoring of Protected
Visual Environments (IMPROVE) monitors that are in place in a number of
locations around the country to characterize fine particle levels and
visibility in mandatory Federal Class I areas (e.g., certain national
parks and wilderness areas). The need for coordination and integration
of visibility-oriented monitoring sites will increase when EPA proposes
rules under section 169A of the Act to supplement the secondary NAAQS
in addressing regional haze. More detailed guidance on monitoring and
assessment requirements will be provided when those rules are proposed.
This will include details on topics such as monitor placement,
monitoring methodology, duration of sampling and frequency of sampling.
It is anticipated, however, that the existing IMPROVE network, together
with sites established under this proposal, would be an integral part
of the network for determining reasonable progress under a regional
haze program.

In the meantime, EPA recommends that States, in conjunction with
EPA and Federal land managers, explore opportunities for expanding and
managing PM<INF>2.5 and visibility monitoring networks in most
efficient and effective ways to meet the collective goals of these
programs. To facilitate this, EPA has proposed changes in Appendix C
below, to allow use of existing or new IMPROVE monitoring sites to meet
the requirements for a transport and/or background site for the
proposed PM<INF>2.5 standards. States should consider the feasibility
of siting new transport/background and/or visibility monitoring
locations at or near mandatory Federal Class I areas currently without
an IMPROVE site so that such sites could provide data to characterize
both fine particle levels and visibility in or near Class I areas. It
is EPA's intent that monitoring conducted for purposes of the PM
primary and secondary NAAQS (including background and transport sites),
and for visibility protection be undertaken as one coordinated national
PM monitoring program, rather than as a number of independent networks.
It is recognized by EPA as well as many outside groups including
the Clean Air Act Advisory Committee's Subcommittee on Ozone,
Particulate Matter, Regional Haze Implementation Programs and the
National Research Council in its 1993 report ``Protecting Visibility in
National Parks and Wilderness Areas'' that chemical speciation of PM
data would permit development of more effective control strategies to
better target those sources of emissions that are causing or
contributing to elevated levels of PM<INF>2.5 and PM<INF>10. Speciation
of PM<INF>2.5 data can also be used to develop reliable estimates of
seasonal and annual average visibility conditions.
Because of the costs associated with conducting filter analysis on
a routine basis, this proposal only requires filters to be archived so
they are available for analysis on an as needed basis. The EPA requests
comment, however, on the extent to which chemical speciation should be
conducted. This would include: (1) Whether specific monitoring sites
should be designated for such analyses; (2) the criteria to be

[[Page 65783]]

used to select sites for speciated sampling and analysis; (3) the
extent and frequency to which speciation should be required by EPA for
at least some monitoring stations and (4) the need for monitoring
methodologies not described in this proposal which may be needed to
facilitate compositional analysis. The EPA recognizes that there is a
need for speciation and other specialized monitoring efforts which are
not specifically required by this proposed rule. Accordingly, EPA will
give these PM monitoring efforts high priority in its section 105
grants program. The Administrator solicits comment on the appropriate
portion of the nation's monitoring resources which should be dedicated
to speciation and collection of special study data relative to the
siting and collection of mass measurements for purposes of comparisons
to the NAAQS and visibility assessments at permanent and temporary
monitoring stations. The estimated cost for the new PM monitoring
program is discussed further in Section IV. R.
Finally, in anticipation of a new regional haze program and
associated additional monitoring requirements, EPA also requests
comment on ways that the future PM and IMPROVE networks can be
coordinated to conserve resources and serve the goals of both the PM
and regional haze implementation program.
This proposed rulemaking is taken in conjunction with the proposed
revisions to the PM NAAQS published elsewhere in today's Federal
Register and pertains to changes in the ambient air monitoring
requirements for particulate matter contained primarily in 40 CFR part
58. A new Federal Reference Method for PM<INF>2.5, and changes to the
definition of PM<INF>10 measurements are proposed in a new Appendix L
and revisions to Appendix J respectively in 40 CR part 50. The
effective date of these proposed monitoring regulations would be 6
months after the actual promulgation date. The EPA is soliciting
comment on all aspects of all of the proposed rules.

III. Proposed Revisions to Part 53

A. Designation of Reference Methods for PM<INF>2.5

The specifications for reference methods for PM<INF>2.5 are
described in Appendix L to part 50, proposed elsewhere in this issue of
the Federal Register. The performance-based specifications for the
operational aspects of a reference method sampler allow various sampler
manufacturers to design and fabricate different samplers that would
meet the specifications. Accordingly, multiple PM<INF>2.5 reference
methods are expected to become available from several manufacturers, as
is the case for reference methods for PM<INF>10 and most gaseous
criteria pollutants. Similarly, each reference method for PM<INF>2.5,
based on a particular sampler, would be formally designated as such by
the EPA under new provisions added to part 53.
These new provisions, primarily contained in a new subpart E, would
require that the applicant submit information and documentation to
demonstrate that a candidate reference method sampler meets the design
specifications set forth in Appendix L of part 50. The provisions would
also require that the applicant carry out specific tests to demonstrate
that the sampler meets all performance specifications. The nature of
these tests and the requirement that they be carried out by the
applicant rather than the EPA is consistent with the current
requirements in part 53 for designating reference methods for other
criteria pollutants.

Since the critical inlet and particle size separation components of
the sampler are specified by design, no wind tunnel or aerodynamic
performance tests of these components would be required. But
documentation would be required to demonstrate that samplers to be sold
as reference methods would be manufactured under an effective quality
control system, such as required in an International Organization for
Standardization (ISO) 1 9001-certified facility, or a quality
control system otherwise certified to meet similar requirements.
Specific tests would be required to verify that the critical PM<INF>2.5
impact or jet diameter was within the design specifications, and that
the surface finish of surfaces required to anodized meets the surface
finish specifications. Also, a checklist certifying that reference
method samplers are or will be manufactured under an acceptable quality
assurance system would have to be completed by an ISO-certified or
equivalent auditor and submitted initially and annually.

\1\ The ISO certification ensures compliance to international
manufacturing standards from the design and engineering
specifications. An ISO certification, or its equivalence for the
manufacturing of the reference samplers is consistent with National
Technology Transfer and Advancement Act Section 12(d), 15 U.S.C.
Section 272 (1996).

The performance tests for reference method samplers would focus on
testing of the sampler's operational performance parameters, the
accuracy of its measurement systems, its field precision, and various
other sampler control functions. A comprehensive test procedure is
proposed for testing a representative candidate sampler for correct
flow rate, flow rate regulation, flow rate measurement accuracy,
ambient air temperature and barometric pressure measurement accuracy,
filter temperature control and measurement accuracy, and sampling time
accuracy. This test procedure would require a temperature-controlled
environmental test chamber, a technique to simulate reduced barometric
pressure, and facilities to generate simulated solar radiation. Other
specific tests are proposed to test the sampler's post-sampling filter
temperature control, leak check procedure, flow rate cut off function,
and field operational precision. It should be noted that work to test
the feasibility of these proposed test procedures has not been
completed at this time; therefore, some technical changes to the
proposed test procedures may be necessary following the results of that
work.

B. Designation of Equivalent Methods for PM<INF>2.5

In keeping with the EPA's largely performance-based approach for
specification of measurement methods for environmental pollutants,
provision is also proposed for designating equivalent methods for
PM<INF>2.5. These provisions are contained in proposed additions to
subparts A and C and proposed new subparts E and F of part 53. To
minimize the number and extent of performance tests to which candidate
equivalent methods would be subjected, three classes of equivalent
method are proposed to be defined.

The first class (Class I) would include PM<INF>2.5 methods based on
samplers that are very similar to a reference method sampler as
specified in appendix L to part 50. Class I would primarily include
methods based on samplers whose primary difference from reference
method samplers is one or more modifications necessary to provide
capability for collection of several sequential samples automatically
without intermediate operator service. Samplers capable of collecting
multiple sequential samples are important because the sampling
schedules proposed in Sec. 58.13 of part 58 call for daily sampling for
certain SLAMS. With such a requirement, there is an expected need for
samplers that will permit the collection of the required daily samples
without the need for an operator to visit the site on a daily basis or
for installing multiple samplers at the site. (Since the samplers would
need to sample from midnight to midnight, a minimum of two single day
samplers would be

[[Page 65784]]

required for full daily sampling; however, as a practical matter,
additional single day samplers would generally be needed at a daily
monitoring site to cover weekends, holidays, and personnel and
scheduling logistics.) A sampler capable of automatically collecting
five sequential samples would permit twice-weekly servicing of a
monitoring site (assuming sample filters can be retrieved and reloaded
on the inactive channels without affecting the actively sampling
channel).

Since the design of sequential samplers is not specified
explicitly, sampler manufacturers would be able to design and develop
their own techniques to provide for this capability. Where the
sequential sample technique consists of relatively minor or simple
modifications of the reference method sampler, the sampler would be
classified as a Class I candidate equivalent method. (Sequential
samplers would also be possible as Class II or III equivalent methods.)
Class I equivalent method sequential samplers would have to be
tested to make sure that the modifications required to provide for
sequential sampling do not significantly compromise sampler
performance. However, because of their similarity to the reference
method sampler, the only additional test requirement for most Class I
candidate equivalent methods--in addition to the tests and performance
requirements applicable to reference method samplers--would be a test
for possible loss of PM in any new or modified components in the
sampler inlet upstream of the sample filter. This additional test for
Class I samplers is set forth in the proposed new Subpart E, along with
the tests for reference method samplers.
Class II equivalent methods would include all other PM<INF>2.5
methods that are based on a 24-hour integrated filter sample which is
subjected to subsequent moisture equilibration and gravimetric mass
analysis, but with an associated sampler having substantial deviations
from the design or performance specifications for reference method
samplers. These samplers may have a different inlet, a different
particle size separator, a different volumetric flow rate, a different
filter or filter face velocity, or other significant differences. More
extensive performance testing would be required for designation of
Class II candidate equivalent methods, with various tests required
depending on the nature and extent of the differences between the
candidate sampler and specified reference method samplers. These tests
include a full wind tunnel evaluation, a wind tunnel inlet aspiration
test, a static fractionator test, a fractionator loading test, and a
volatility test. The tests and their specific applicability to various
types of candidate Class II equivalent method samplers are set forth in
proposed new subpart F.

Finally, Class III equivalent methods would include any candidate
PM<INF>2.5 methods that could not qualify as Class I or Class II. This
class would include any filter-based integrated sampling method having
other than a 24-hour PM<INF>2.5 sample collection interval followed by
moisture equilibration and gravimetric mass. More importantly, class
III would also include filter-based continuous or semi-continuous
methods, such as beta attenuation instruments, harmonic oscillating
element instruments, and other complete in situ monitor types, as well
as non-filter-based methods such as nephelometry or other optical
instruments.

The testing requirements for designation of Class III candidate
methods would be the most stringent, since quantitative comparability
to the reference method would have to be shown under various potential
particle size distributions and aerosol composition. However, because
of the variety of measurement principles and types of methods possible
for Class III candidate equivalent methods, the test requirements would
have to be individually selected or specifically designed or adapted
for each such type of method. Therefore, the EPA believes that it is
not practical to attempt to develop and explicitly describe the test
procedures and performance requirements for all of these potential
Class III methods a priori. Rather, it is proposed that the test
procedures and performance requirements applicable to specific Class
III candidate methods would be determined by the EPA on a case-by-case
basis upon request, in connection with each proposed or anticipated
application for a Class III equivalent method determination. In this
regard, the EPA is interested in receiving comments pertinent to the
nature and extent of tests that would be appropriate and effectual in
determining the performance of various types of Class III candidate
equivalent methods relative to the performance of reference methods for
PM<INF>2.5.

All classes of candidate equivalent methods would have to be fieldtested
to determine their comparability to measurements obtained with
collocated reference methods. For Classes I and II, these collocated
field test requirements are specified explicitly in Subpart C, which is
proposed to be revised to include the specific requirements for
PM<INF>2.5 candidate equivalent methods. The proposed requirements for
PM<INF>2.5 methods are generally patterned after the existing
requirements for PM<INF>10 candidate methods.
However, because of the need for greater measurement precision for
PM<INF>2.5, the comparability specifications, summarized in Table C-4,
are somewhat more stringent than those previously established for
PM<INF>10. Also, for Class II candidate equivalent methods--where two
different test sites are required--more definitive specifications are
proposed for the tests sites in terms of the PM<INF>2.5 to PM<INF>10
measurement ratio for the test samples. This is necessary because
experience with PM<INF>10 measurements has indicated that PM
measurements made with dissimilar samplers are often considerably
affected by differences in the ``character'' of the PM at different
monitoring sites, as represented by differences in particle size
distribution, composition, density, humidity, and other factors. For
purposes of the comparability test, the character of the PM at each
test site is represented by the measured PM<INF>2.5 to PM<INF>10 ratio,
which must be greater than 0.75 for one site and less than 0.40 at the
other site. (More definitive tests of PM character at the test site are
deemed too difficult or costly to carry out for purposes of the
comparability test.) Insuring comparability to reference method
measurements at sites having profoundly different character of PM is
critically important for Class II (and Class III) candidate equivalent
methods. Note, however, that the PM<INF>2.5 to PM<INF>10 ratio
requirement does not apply to testing of Class I candidate methods,
where only one test site is required.

C. Quality Assurance

Accurate measurement of ambient particulate matter concentrations
is severely hampered by the impracticality of providing PM
concentration standards for field (or even laboratory) testing of
ambient samplers or monitors. Therefore, it is necessary to rely on a
specific, well-defined reference method, uniformity of reference method
devices and procedures, and continual assessment of bias and operating
precision. For the purposes of this regulation, PM<INF>2.5
concentration measurements would be referenced to measurements made
with a reference method sampler in accordance with the reference method
as specified in Appendix L of part 50 of this chapter. Monitoring for
PM<INF>2.5 requires greater attention to achieving data of high
quality, with minimal imprecision and

[[Page 65785]]

relative error. These higher quality monitoring data are essential to
reduce the chance that PM<INF>2.5 measurements would potentially cause
unjustified health risk to the population, when measurements
underestimate true concentrations, or unnecessary control requirements,
when measurements overestimate the true concentrations.
To meet a data quality objective of <plus-minus>15% precision for
ambient PM<INF>2.5 attainment measurements, enhanced quality assurance
would be required in all areas relating to sampler performance
including sampler manufacturing and sampler operation. This is
especially important because a reference method sampler is proposed to
be used to audit other field monitors, as described later.
Designated reference and equivalent method samplers and monitors
would be required to be manufactured in a manufacturing facility that
is either (1) an ISO 9001-registered manufacturing facility, with
registration maintained continuously, or (2) a facility that can be
demonstrated, on the basis of information submitted to the EPA, to be
operated according to an EPA-approved and periodically audited quality
system which meets, to the extent appropriate, the same general
requirements as for an ISO-registered facility. (This requirement is
referred to in this document as an ISO-registered facility, regardless
of the procedure taken for EPA approval.)
In addition to the ISO registration (or equivalent) requirement, a
quality assurance manufacturing checklist would have to be submitted
annually attesting that the appropriate quality assurance procedures
are routinely implemented in the manufacturing of samplers sold as
reference or equivalent method samplers. This check list would have to
be signed by an ISO-certified auditor or by an auditor who, based on
information submitted to the EPA, meets the same general requirements
as provided for ISO-certified auditors. (Similarly, an auditor approved
by EPA through either mechanism is referred to in this document as an
ISO-certified auditor.) This requirement allows for the demonstration
of consistency in production and sustained uniformity in design and
operation. Further, all testing related to an application for a
reference or equivalent method determination under part 53 would have
to be carried out in accordance with ISO 9001 and ANSI/ASQC E4
standards.

It is believed that these requirements are necessary to insure that
all samplers or analyzers sold as reference or equivalent methods are
manufactured to the high standard required to achieve the needed data
quality. These procedures are in keeping with the developing
international standards for manufacturing in this and other industries.
However, comments on the appropriateness and impact of these proposed
requirements are solicited. While these requirements are currently
proposed to apply only to the manufacture of PM<INF>2.5 monitors,
extending these requirements to the manufacture of PM<INF>10 monitors
and possibly other types of SLAMS monitors will likely be considered at
a later time.

A new operational requirement would also have to be met by each
PM<INF>2.5 sampler or monitor to retain its designation as a reference
or equivalent method. Each user agency operating a SLAMS site would be
required to obtain at least 6 collocated measurements (audits) per year
with a reference method ``audit'' sampler for each routinely operating
PM<INF>2.5 monitor. The data obtained from these collocated audits
would be used to determine a national network integrated operating
precision and relative accuracy performance indicator for each
designated method. A PM<INF>2.5 monitoring method that fails to meet
the specified limits for this performance indicator would be subject to
possible cancellation of its reference or equivalent method designation
under the provisions of Sec. 53.11. For more information on this
provision, see section 6 of proposed revisions to Appendix A of part 58
and its associated preamble, set forth elsewhere in this Federal
Register.

D. Other Changes

A number of other relatively minor technical changes are proposed
to Appendix A, some of which affect designation of reference or
equivalent methods for other criteria pollutants as well as for
PM<INF>2.5. These changes include new definitions and clarifications of
existing definitions in Sec. 53.1; clarifications of the reference and
equivalent method designation requirements for methods for all
pollutants, including the new classes of equivalent methods for
PM<INF>2.5 and a new table summarizing all the designation
requirements; and updating of the name of the EPA laboratory to which
applications are to be sent. Additional changes include proposed
clarifications of the content of information required in submitted
applications regarding the candidate method test data, manufacturing
quality assurance system, and product warranty, and the content
required in the operation or instruction manual associated with a
candidate method sampler or analyzer.

Also, because of the increasing complexity of anticipated candidate
methods for all criteria pollutants, an increase in the EPA's time
limit for processing applications for reference and equivalent methods,
from 75 to 120 days, is proposed. Finally, it is proposed (under
Sec. 53.4) that applicants for a PM<INF>2.5 reference or equivalent
method determination be required to provide a sampler or analyzer that
is representative of the one associated with the candidate method for
inspection and possible testing by the EPA in connection with
processing of the application.

IV. Discussion of Proposed Revisions to Part 58

A. Section 58.1--Definitions

The revisions proposed today would revise the definition of the
term traceable and add definitions of the terms Consolidated
Metropolitan Statistical Area (CMSA), core SLAMS, equivalent methods,
Metropolitan Statistical Area (MSA), monitoring planning area (MPA),
monitoring plan, PM<INF>2.5, Primary Metropolitan Statistical Area
(PMSA), population-oriented, reference method, SAZ (SAZ), SPM fine
monitors, and Annual State Monitoring Report.

B. Section 58.13--Operating Schedule

PM<INF>10 Sampling. The current operating schedule for PM<INF>10
is based primarily on an analysis of the ratio of measured PM<INF>10
concentrations to the controlling PM<INF>10 standard. Depending upon
the ratio, the sampling frequency is either every day, every other day,
or every sixth day. The proposed operating schedule would reduce the
sampling frequency at all PM<INF>10 sites to once every sixth day.
The Administrator has proposed a new 24-hr PM<INF>10 standard based
on the 98th percentile which offers a more stable statistical form. She
has also solicited comment on the need to retain any 24-hour PM<INF>10
standard. Unlike the current 24-hr PM<INF>10 standard, the proposed
standard, if adopted, would not place emphasis on the most extreme 24-
hr concentrations, especially in areas influenced by fugitive dust.
Furthermore, more emphasis for control requirements is anticipated to
be placed on annual average concentrations and fewer nonattainment
areas (i.e. violation areas) are expected to be based on peak daily
concentrations. Consequently, 1 in 6 day sampling should be sufficient
to support the new PM<INF>10 NAAQS and a less dense monitoring network
would also be needed. Comments are solicited on the appropriate
sampling schedules

[[Page 65786]]

for PM<INF>10 sites if the 24-hour NAAQS for PM<INF>10 is retained.
2. PM<INF>2.5 Sampling. Core PM<INF>2.5 SLAMS (including NAMS and
Core SLAMS collocated at PAMS sites) would be required to sample every
day, unless an exception is approved by EPA during established seasons
of low PM pollution during which time a minimum of once in 6 days
sampling would be permitted. Non-core SLAMS sites would generally be
required to sample a minimum of once every sixth day, although episodic
or seasonal sampling could also be possible (e.g., in areas where
significant violations of the 24-hour NAAQS are expected or at sites
heavily influenced by regional transport or episodic conditions).
Special purpose monitors, however, may sample on any sampling schedule.
There is currently very little PM<INF>2.5 measurement data. New
networks must be established as expeditiously as possible to help
characterize the nature and extent of PM<INF>2.5 ambient air quality
nationwide. Daily sampling for PM<INF>2.5 is especially important
during the first few years of the new PM<INF>2.5 monitoring program to
allow for the collection of complete sets of data in order to help with
identifying temporal patterns and to understand the episodic behavior
of fine particles.

Although daily sampling with manual methods is labor intensive due
to site visits and filter equilibration and weighing, semi-automatic
sequential samplers are anticipated to be approvable as class I
equivalent samplers (under the provisions of Part 53) which will
simplify the data collection process. The EPA solicits comments on the
need to extend the start date for a requirement to perform everyday
sampling until the time when Class I equivalent samplers have been
approved by the Agency.

In addition, alternative PM<INF>2.5 operating schedules which
combine intermittent sampling with the use of acceptable continuous
fine particle samplers are approvable at some core sites. This
alternative is intended to give the States additional flexibility in
designing their PM<INF>2.5 monitoring networks and to permit data from
continuous instruments to be telemetered. This would facilitate public
reporting of fine particle concentrations, allow air pollution alerts
to be issued and episodic controls to be implemented (as currently done
in woodburning areas for PM<INF>10). Furthermore, this would permit
monitoring agencies to take advantage of new and improved monitoring
technologies that should become available during the first few years
following the promulgation. As proposed, applicability of the
alternative depends on population size of the monitoring area and
PM<INF>2.5 air quality status.

After the initial 3 years of PM<INF>2.5 data collection and after
characterization of PM<INF>2.5 levels, determination of violation areas
and development of State Implementation Plans), reductions in the
frequency of PM<INF>2.5 sampling may be appropriate. The EPA welcomes
comments on the need for continued long-term monitoring with reference
or equivalent samplers on an every day schedule at some or all
monitoring stations and on the appropriateness of the criteria for
allowing alternative schedules.

C. Section 58.14--Special Purpose Monitors

Special purpose monitoring is needed to help identify potential
problems, to help define boundaries of problem areas, to better define
temporal (e.g., diurnal) patterns, to determine the spatial scale of
high concentration areas, and to help characterize the chemical
composition of PM (using alternative samplers and supplemental
analyzers), especially on high concentration days or during special
studies. Special purpose monitors are an important part of the overall
PM monitoring program, and sufficient EPA and State resources must be
allocated for their use.

Today's revisions propose that special purpose PM<INF>2.5 and
PM<INF>10 monitors may sample with any measurement method on any
sampling schedule. However, the data from SPM's would not be used for
attainment/nonattainment designations if the monitoring method is not a
reference or equivalent method or does not meet the requirements of
Section 2.4 of Appendix C of Part 58. Moreover, in order to encourage
the deployment of SPM's, today's revisions propose that nonattainment
designations will not be based on data produced at an SPM site with any
monitoring method for a period of 3 years following the promulgation
date of the NAAQS.

The rationale for this concept is based on the need for to
encourage building from ``ground zero'' a monitoring infrastructure.
Such an infrastructure is needed because of the complexity of the
PM<INF>2.5 problem and the relative paucity of PM<INF>2.5 data to
determine where problem areas lie, and the lack of information about
sources and formation of aerosols in particular areas. The requirements
for the NAMS, minimum core SLAMS, and minimum additional SLAMS sites,
described in this notice, are designed to provide much of the
information needed to merely define the location of problem areas.
There is a need, however, to look beyond this minimal network to
create an ``optimal'' network that would gather air quality data over a
wider geographic area. The optimal network would consist of SLAMS
monitors in addition to the required minimums and also SPM's. There are
several reasons for a moratorium on regulatory use of data from the
during the first 3 years following promulgation of the NAAQS:
(1) SPM data have historically supplemented the SLAMS network to
provide the States with a flexible monitoring program. Although the SPM
monitoring does not have to use reference or equivalent monitors, the
States tend to use these monitors for data collection. And although SPM
data are not required to be submitted to EPA, the States tend to enter
all such data into the AIRS data base. Because of the paucity of
PM<INF>2.5 data, we want to encourage both the collection--with
reference or equivalent monitors--and the reporting of as much new
PM<INF>2.5 data as possible. This includes SPM data.
(2) There is a general reluctance among State and local governments
and businesses to monitor ambient air quality beyond those minimum
requirements contained in regulations promulgated by the Environmental
Protection Agency (EPA) in the Code of Federal Regulations at Part 58.
The reluctance is based in part on the fact that areas have
historically been designated to nonattainment where monitoring shows
violations of the NAAQS and then classified according to the
seriousness of the air pollution problem. Currently, such a
nonattainment designation and classification automatically trigger the
State implementation attainment planning and demonstration
requirements, potential stationary and mobile source emission controls,
nonattainment new source review for sources wanting to locate or expand
in the new nonattainment area, and possibly additional requirements
relating to nonattainment of the NAAQS. Thus, to many affected parties,
the current regulatory system results in a disincentive for detecting
violations.

(3) The EPA is evaluating a concept involving the identification of
areas that have measured or modeled violations and subsequent
identification of other areas whose emissions contribute to those
violations. The new required PM<INF>2.5 monitoring network, however,
may be insufficient to determine all such violation areas and
contributing areas, and therefore additional monitors may be desirable.
Ambient air

[[Page 65787]]

monitoring will play an important and expanded role in defining
violating and contributing areas; with a moratorium on the regulatory
use of SPM data, States and businesses would have an additional
incentive to monitor for data to more accurately determine the extent
of these areas.

(4) During the initial stages of development of a new PM<INF>2.5
network, there is a greater need for experimental sampling--to move
samplers around, to sample for short periods of time, and to utilize
different methods. Incomplete data sets may not be fully representative
of local air quality. For these and other similar reasons, there is a
need for a pilot network that would not be subjected to the same rules
as the full SLAMS network.

(5) Finally, collecting data at a number of sites beyond either the
minimum or optimal number proposed in these regulations would support
modeling studies to better define pollution problems, identification of
potential pollution problems for enhanced air management programs, the
design and implementation of episodic control plans to encourage quick
response actions for voluntary emission reduction measures to lower
pollution and thereby possibly avoiding nonattainment or ``bump-ups'',
and to measure progress toward attainment by relating air quality to
population.

The system of SPM's would at first not be part of the full required
or even the ``optimal'' network. To provide the best kind of
information, EPA believes that properly sited Federal Reference or
Equivalent Methods be used for these SPM efforts in order to collect
technically credible data. The EPA also believes that data from those
efforts be reported to AIRS so that they are generally available to the
public at large and to those who need them for understanding the nature
of the problem and for developing solutions and control strategies.
In proposing a 3-year moratorium on the regulatory use of SPM data,
EPA is trying to establish an incentive for States to engage in this
additional SPM monitoring using properly sited Federal Reference or
Equivalent Monitors. The data from these SPM's would supplement the
data collected by SLAMS sites. Although the SPM data would be exempt
from regulatory use during the 3-year moratorium, they would
nevertheless be evaluated by the State during its annual SLAMS network
review. A notice of NAAQS violations resulting from PM SPM``s should be
reported to EPA, such high concentrations should be evaluated by the
State in the design of its overall SLAMS network and considered by EPA
in its review and approval of the State''s monitoring plan. Therefore,
during the first 3 years, the SPM data would still play an important
role in the regulatory process. After the proposed 3-year exemption
period, SPM locations should be considered as potential SLAMS in the
State's development and subsequent EPA reviewal process of their
monitoring plan network, if the sites record high concentrations which
indicate potential violations of the PM NAAQS (for either PM<INF>10 or
PM<INF>2.5) and have been operating for at least 6 months.
The EPA could have taken a different approach to this problem and
not propose a moratorium on the regulatory use of data from the SPM
sites. States would still be able to deploy SPM monitors in ways to
avoid legal consequences if an exceedance of the NAAQS were found. For
instance, any State may use non-reference or non-equivalent methods,
which do not meet EPA specifications. Any State could site monitors so
that they do not meet EPA siting criteria. Such monitoring would avoid
the above-described legal entanglements associated with any NAAQS
exceedances, because the data collected would not, under current EPA
regulations, be valid for use in comparison to the NAAQS. Moreover, any
State could simply not submit the SPM data to EPA.
The approach described in the above paragraph, however, does have
major disadvantages. For instance, an approach that uses unacceptable
monitors or siting would result in data that--even if close to being
representative of the area or what a properly sited acceptable monitor
would measure, would still be clouded with questions regarding its
accuracy or precision, which would limit their value in the kinds of
analyses mentioned above. In the case of data simply not submitted to
EPA, data would not be available to either other States that would be
working on development of a solution to the PM-fine problem, or, more
important, to the public at large so that they could be aware if there
really are problems detected by the monitor.
In light of these concerns, EPA's proposal is an attempt to take a
more straightforward approach, which will encourage collection of
additional data that is technically credible and publicly available,
and therefore address the Act's mandate for EPA to take the lead in
this matter, as found in section 103(c).

D. Section 58.15--PM<INF>2.5 NAAQS Eligible Monitors

This new section is proposed to define the PM<INF>2.5 monitors
eligible for use in determining compliance with the PM<INF>2.5 annual
and 24-hour NAAQS. The EPA proposes that States identify on EPA's AIRS
monitoring site file, all PM<INF>2.5 sites eligible for both annual
NAAQS comparisons and 24-hour comparisons and those only eligible for
24-hour (daily) comparisons. The former sites are intended to be
population oriented spatial averaging sites and the latter are intended
to represent population-oriented ``hot spot'' locations. The reasons
for the different types of monitors are discussed in the preamble to 40
CFR part 50.

E. Section 58.20--Air Quality Surveillance: Plan Content

The revisions proposed today would require States to submit a PM
monitoring plan to the Regional Administrator within 6 months of the
effective date promulgation. The monitoring plan would describe the PM
monitoring strategy based on the use of SLAMS (including NAMS and PAMS)
and SPM's for PM<INF>10 and PM<INF>2.5; describe the phase-in of
PM<INF>2.5 monitors and changes in the existing PM<INF>10 monitoring
program; describe monitoring objectives and scales of
representativeness to facilitate subsequent interpretation of data;
define sampling schedules; denote sites intended for comparison to the
PM NAAQS; and define the monitoring planning areas (MPA's) and SAZ's
(SAZ's) within the State. It should also reference the revised quality
assurance plan which is required by Appendix A to Part 58. In regard to
the use of air quality data for making comparisons to the NAAQS and
other SIP related purposes, the monitoring plan shall also describe the
SPM's whose data the State intends to use for SIP purposes. The
monitoring plan must also provide for an annual review for termination,
relocations, or establishment of new SLAMS or core SLAMS.

F. Section 58.23--Monitoring Network Completion

Under the revisions proposed today, the PM networks would be
expected to be completed within 3 years of the effective date of
promulgation. While new PM<INF>2.5 networks are developed, existing
PM<INF>10 networks should be considered for reductions consistent with
the goals stated in the background section earlier. For PM<INF>2.5, a
3-year phase-in would be used. The proposed schedule for deployment of
new required PM<INF>2.5 monitors is described

[[Page 65788]]

here. During the first year, a minimum of one monitoring planning area
per State would be required to have core PM<INF>2.5 SLAMS. This area
would be selected by the State according to the likelihood of observing
high PM<INF>2.5 concentrations and according to the size of the
affected population. In addition, one PM<INF>2.5 site would be
collocated at one site in each of the PAMS areas. During the second
year, all other core population-oriented PM<INF>2.5 SLAMS, and all core
background and transport sites, must be fully operational. During the
third year, any additional required PM<INF>2.5 (non-core) SLAMS must be
fully deployed and all NAMS sites must be selected from core SLAMS and
proposed to EPA for approval.

G. Section 58.25--System Modification

No changes to the regulatory language are proposed to Sec. 58.25;
however, under the revisions proposed today, the annual system
modifications review must include changes to PM<INF>2.5 site
designations (e.g., NAAQS comparison sites), the number or boundaries
of monitoring planning areas and/or SAZ's.

H. Section 58.26--Annual State Monitoring Report

Under the current regulations, States are required to submit an
annual SLAMS data summary report. Under today's proposed revisions,
this report shall be expanded to include additional information. First,
the new State Monitoring report shall describe the proposed changes to
the State's Monitoring Plan, as defined in Sec. 58.20. It shall include
a new brief narrative report to describe the findings of the annual
SLAMS network review, reflecting within year and proposed changes to
the State air quality surveillance system, and to provide information
on PM SPM's and other PM sites described in the monitoring plan
regardless of whether data from the stations are submitted to EPA
(including number of monitoring stations; general locations; monitoring
objective; scale of measurement; and appropriate concentration
statistics to characterize PM air quality such as number of
measurements, averaging time, and maximum, minimum, and average
concentration). The latter is needed for EPA to ensure that a proper
mix of permanent and temporary monitoring locations are used, that
populated areas throughout the nation are monitored, and to provide
needed flexibility in the State monitoring program. The content of this
brief report shall be in accordance with EPA guidance, and will be
available at the time of promulgation of the final Part 58 rule.
Next, States would be required to describe the proposed changes to
existing PM networks. Proposed changes to the existing networks may
include modifications to the number, size, or boundaries of Monitoring
Planning Areas or SAZ's, number and location of PM SLAMS; number or
location of core PM<INF>2.5 SLAMS; alternative sampling frequencies
proposed for PM<INF>2.5 SLAMS (including core PM<INF>2.5 SLAMS and
PM<INF>2.5 NAMS); core PM<INF>2.5 SLAMS to be designated PM<INF>2.5
NAMS; and PM SLAMS to be designated PM NAMS. SLAMS with NAAQS
violations should be considered to become new or replacement core
sites, and SPM's with NAAQS violations could become part of the SLAMS
network. The proposed changes should be developed in close consultation
with the appropriate EPA Regional Office and submitted to the
appropriate Regional Office for approval. The portion of the plan
pertaining to NAMS would be submitted to the Administrator (through the
appropriate Regional Office).

Finally, as a continuation of current regulations, the States shall
be required to submit the Annual SLAMS summary report and to certify to
the Administrator that the SLAMS data submitted are accurate and in
conformance with applicable Part 58 requirements. Under the revisions
proposed today, States would also be required to submit annual
summaries of SPM data to the Regional Administrator for sites included
in their Monitoring Plan and to certify that such data are similarly
accurate and likewise in conformance with applicable Part 58
requirements or other requirements approved by the Regional
Administrator, if these data are intended to be used for SIP purposes.
During the first 3 years following promulgation, the monitoring
plan and any modifications of it must be submitted to EPA by July 1
(starting on the year following promulgation) or by alternate annual
date to be negotiated between the State and Regional Administrator,
with review and approval/disapproval by the Regional Administrator
within 45 days. After the initial 3-year period or once a SAZ has been
determined to be violating any PM<INF>2.5 NAAQS, then changes to a
monitoring planning area will require public review and notification to
ensure that the appropriate monitoring locations and site types are
included. Specific comment on or suggestions for alternate procedures
that are not unduly time consuming or burdensome to allow public review
and comment on changes in MPA's, SAZ's, or other elements of a
monitoring plan developed by a State or local air pollution control
agency are especially welcome.

I. Section 58.30--NAMS Network Establishment

The revision proposed today would designate 6 months after the
effective date of promulgation as the date by which the NAMS network
portion (to be derived from core PM<INF>2.5 SLAMS) of each State's
SLAMS network must be fully described and documented in a submittal to
the Administrator (through the appropriate EPA Regional Office). At
this time, a State's NAMS PM<INF>10 network must be reaffirmed if no
changes are made to the existing network and if changed must also be
fully described and documented in a submittal to the Administrator
(through the appropriate EPA Regional Office).

J. Section 58.31--NAMS Network Description

Today's proposed revision would require that the NAMS network
description also include for PM<INF>2.5 the monitoring planning area,
SAZ, and the site code designation to identify which site will be used
to determine violation of the appropriate NAAQS (annual or 24-hour).

K. Section 58.34--NAMS Network Completion

The revision proposed today would designate 3 years after the
effective date of promulgation as the date by which the State must have
all PM<INF>2.5 NAMS in operation, and 1 year after the effective date
of promulgation as the date by which the State must have made all
changes to the existing PM<INF>10 NAMS.

L. Section 58.35--NAMS Data Submittal

This section defines the data submittal requirements for NAMS and
SLAMS. Consistent with current requirements, only the total mass
derived from PM<INF>10 and PM<INF>2.5 SLAMS would be required to be
submitted to EPA. However, EPA encourages reporting all data from
monitors proposed in the State monitoring plan. These optional data
would include data from SPM's and compositional data from all monitors.

M. Appendix A--Quality Assurance Requirements for SLAMS

Meeting the more stringent data quality objectives for ambient
PM<INF>2.5 monitoring will require considerably enhanced quality
assurance in the areas of sampler operation, filter handling, data
quality assessment, and other

[[Page 65789]]

operator-related aspects of the PM<INF>2.5 measurement process.
Most operational quality control aspects are specified in Appendix
A in general terms. For PM<INF>2.5, however, explicit, more stringent,
requirements are proposed for sample filter treatment--including the
moisture equilibration protocol, weighing procedures, temperature
limits for collected samples, and time limits for prompt analysis of
samples. These requirements, which are specified in the reference
method set forth in proposed new Appendix L to part 50, will help to
control measurement precision. Additional or supplemental detailed
quality assurance procedures and guidance for all operator-related
aspects of the PM<INF>2.5 monitoring process will be developed and
published as a new Section 2.12 of the EPA's, Quality Assurance
Handbook for Air Pollution Measurement Systems series to assist
monitoring personnel in maintaining high standards of data quality.
Procedures for continually assessing the operational quality of the
SLAMS monitoring data are specified explicitly in Appendix A of part
58. Perhaps the most significant new data quality assessment
requirement proposed for PM<INF>2.5 monitoring is the requirement that
each routinely operating PM<INF>2.5 ``compliance'' monitor must be
``audited'' at least 6 times per year. A compliance monitor is a
monitor at a site which is included in the PM monitoring plan and whose
data is intended for comparison to the NAAQS as described in Appendix
D. This is the first time a requirement has been proposed to assess the
relative accuracy of the mass concentration measured by a SLAMS PM
monitor.

Each of these 6 ``audits'' would be performed by the monitoring
agency and would consist of concurrent operation of a collocated
reference method audit sampler along with the routinely operated
compliance sampler or monitor. The data from these collocated audits
would be pooled by the EPA to assess the performance of PM<INF>2.5
monitoring methods on a national basis and for each reporting
organization. These data would also be used in a screening test of the
performance of individual monitors at each monitoring location. Six has
been determined to be the minimum number of audit data points needed to
yield a reasonable assessment of individual monitor operational
performance on an annual basis. This number is analagous to the data
requirements for the precision and accuracy assessments for PM<INF>10,
PM<INF>2.5 and other pollutants described in Section 5.
The integrated operating precision and relative accuracy, evaluated
annually, would have to meet a limit of <plus-minus>15 percent. A
monitoring method that fails this requirement nationally would be
placed in a probationary status pending resolution of the inadequate
performance or possible cancellation of its reference or equivalent
method designation under the provisions of Sec. 53.11 of part 53 of
this chapter. While this action would not result in immediate
cancellation of the designation, it would require the method applicant
(e.g., the manufacturer) to correct the method performance problems or
to submit alternative evidence or arguments (possibly in collaboration
with other affected entities) that the method's designation should not
be canceled.

Reporting organizations whose monitoring data failed to meet this
requirement (or are significantly worse than the national norm) would
be notified that its quality assurance plan or procedures need
improvement. Similarly, monitoring data from individual sites that fail
the screening test would require remedial action or replacement of the
monitoring method. Note, however, that failure of either of these tests
or the national test would not automatically cause the associated
monitoring data to be invalid.

Comments are solicited on these method operating performance audits
and particularly on the potential use of the audit data by EPA to: (1)
Determine a national network operating precision and accuracy
performance indicator for each type of designated method, (2) determine
the operational performance of methods used by reporting organizations
relative to the national norm, and (3) consider cancellation of the
reference or equivalent method designation of methods failing to meet
the <plus-minus>15 percent operational performance specification.
Other data assessment requirements proposed in Appendix A for
PM<INF>2.5 monitoring networks are patterned after the current
requirements for PM<INF>10 networks and are intended to supplement the
audit procedure. PM<INF>2.5 network monitors would be subject to
precision and accuracy assessments for both manual and automated
methods, using procedures similar or identical to the current
procedures required for PM<INF>10 monitoring networks. Results of these
field tests performed by the monitoring agencies (along with the
results of the field audits) would be sent to the EPA, which then would
carry out the specified calculations. These calculated statistics would
become part of the annual assessment of the quality of the monitoring
data.

For automated methods, the additional assessment of the precision
would consist of a one-point precision check performed at least once
every 2 weeks on each automated analyzer used to measure PM<INF>2.5.
This precision check would be made by checking the operational flow
rate of the analyzer. A standard precision flow rate check procedure
similar to that currently used for PM<INF>10 network assessments is
proposed. Also proposed is an alternative procedure where, under
certain specific conditions, it would be permissible to obtain the
precision check flow rate data from the analyzer's internal flow meter
without the use of an external flow rate transfer standard. (This
alternative procedure would also be made applicable to PM<INF>10
methods.)

The additional accuracy assessment procedure proposed for
PM<INF>2.5 automated methods is also similar to that used for PM<INF>10
networks, although each PM<INF>2.5 analyzer would have to be audited
quarterly rather than annually, as is the current requirement for
PM<INF>10 analyzers. The assessment would be performed on the
analyzer's operational flow rate using a flow rate transfer standard,
with the accuracy calculated from the percent difference between the
actual flow rate and the corresponding flow rate indicated by the
analyzer.

For manual methods, an additional precision assessment would be
calculated from the data collected from collocated samplers, as is
currently required for manual PM<INF>10 methods. The number of
collocated samplers within each PM<INF>2.5 network is proposed to be
based upon the total number of samplers within the reporting
organization's network. For 1 to 10 total sites, 1 site would be
selected for collocation; for 11 to 20 total sites, 2 sites would be
selected for collocation; and if a reporting organization has over 20
total sites, then 3 sites would be selected for collocation. As for
PM<INF>10, one sampler of the collocated pair would be designated as
the primary sampler whose samples would be used to report air quality
for the site, and the other would be designated as the duplicate
sampler. The percent differences in measured concentration between the
two collocated samplers would be used to calculate this additional
network precision.

The accuracy of the flow rate system of manual methods for
PM<INF>2.5 would be determined, as for automated methods, by auditing
each sampler each calendar quarter. Using a flow rate transfer
standard, each sampler would be audited at its normal operating flow

[[Page 65790]]

rate. The percent differences between these flow rates would be used to
calculate an additional indicator of accuracy.
Although the new quality assurance requirements for PM<INF>2.5
would result in an increase in the quality of the PM monitoring data,
the additional QA/QC checks would entail additional cost to the
monitoring agency. Some of the new QA/QC assessment requirements may
somewhat overlap the similar information provided by other checks, such
as the periodic flow rate checks and the use of collocated samplers in
monitoring networks. Consequently, the EPA solicits comments on the
need to maintain all of these QA requirements and also on the adequacy
of the proposed QA data assessments to ensure the defined quality for
PM<INF>2.5 measurements.

Table A-1, which summarizes the minimum data quality assessment
requirements, would be updated to include the new requirements for
PM<INF>2.5 methods, and other minor, mostly editorial changes are
proposed to Appendix A to update and clarify the language and specific
requirements.

A change to section 2.5 of Appendix A is also being proposed to
provide for technical system audits to be performed by EPA at least
every three years rather than every year. This change to a less
frequent system audit schedule recognizes the fact that for many well
established agencies, an extensive system audit and rigorous inspection
may not be necessary every year. The determination of the extent and
frequency of system audits at an even lower frequency than the proposed
three year interval is being left to the discretion of the appropriate
Regional Office, based on an evaluation of the Agency's data quality
measures. This change would afford both the EPA and the air monitoring
agencies flexibility to manage their air monitoring resources to better
address the most critical data quality issues.
N. Appendix C--Monitoring Methodology

Section 2.2 of Appendix C is proposed to be amended to allow the
use of PM<INF>10 monitors as surrogates for PM<INF>2.5 monitors for
purposes of demonstrating compliance with the NAAQS. However, following
the measurement of a PM<INF>10 concentration higher than the 24-hour
PM<INF>2.5 standard or an annual average concentration higher than the
annual average PM<INF>2.5 standard, the PM<INF>10 monitor would have to
be replaced with a PM<INF>2.5 monitor. In addition, for NAMS that are
converted to PM<INF>2.5 monitoring from PM<INF>10 monitoring, the
PM<INF>10 monitoring must continue concurrently with the PM<INF>10
monitoring for 1 year following the beginning of the PM<INF>2.5
monitoring.

Appendix C would also be amended to add a new section 2.4
containing provisions that would allow the use at a SLAMS of a
PM<INF>2.5 method that had not been designated as a reference or
equivalent method under part 53. Such a method would be allowed to be
used at a particular SLAMS site to make comparisons to the NAAQS if it
met the basic requirements of the test for comparability to a reference
method sampler for PM<INF>2.5, as specified in Subpart C of part 53 of
this chapter, in each of the four seasons of the year at the site at
which it is intended to be used. A method that meets this test would
then be further subjected to the operating precision and accuracy
requirements specified in section 6 of Appendix A of this part, at
twice the normal evaluation interval (6 audits in 6 months instead of 6
audits in 12 months). A method that meets these requirements would not
become an equivalent method, but the method could be used at that
particular SLAMS site for any regulatory purpose. The method would be
assigned a special method code, and monitoring data obtained with the
method would be accepted into AIRS as if they had been obtained with a
reference or equivalent method. This provision could thus allow the use
of non-conventional PM<INF>2.5 methods, such as optical or open path
measurement methods, which would be difficult to test under the
equivalent method test procedures proposed for part 53.
In addition, Appendix C would also be amended to add two new
sections. A proposed new section 2.5 would clarify that correlated
acceptable continuous (CAC) methods for PM<INF>2.5 approved for use in
a SLAMS under proposed new provisions in Sec. 58.13(f) would not become
de facto equivalent methods. This applies to methods that have not been
designated equivalent and do not satisfy the requirement of Section 2.4
described above. The new section would further clarify that the
monitoring data obtained with CAC methods would be restricted to use
for the purposes of Sec. 58.13(f) and would not be used for making
comparisons to the NAAQS. Proposed new section 2.9 would define socalled
``IMPROVE'' samplers for fine particulate matter and clarify
that IMPROVE samplers, although not designated as equivalent methods,
could be used in SLAMS for monitoring regional background
concentrations of fine particulate matter.
Finally, minor changes are proposed to section 2.7.1 to update the
address to which requests for approval for the use of methods under the
various provisions of Appendix C should be sent, and section 5 to add
additional references.

O. Appendix D

The revisions to Appendix D proposed today would revise Sections 1,
2, 2.8, 3, 3.7, and 5 to incorporate changes made necessary by the
proposed new PM<INF>2.5 NAAQS. Section 1 is revised to add criteria for
core PM<INF>2.5 stations. Two additional SLAMS monitoring objectives
are added: the first is to determine the extent of regional pollutant
transport among populated areas, which may originate from distant
pollutant sources; the second is in support of secondary NAAQS, to
determine the welfare-related impacts in more rural and remote areas
(such as visibility impairment and effects on vegetation). Section 2 is
revised to include information that would be useful in designing
regulatory networks. Section 2.8 and 3.7 are revised to apply to
PM<INF>2.5 as well as PM<INF>10. Section 2.8.1 is added to discuss
monitoring planning areas and SAZ's. Section 2.8.2 is added to address
the PM<INF>2.5 monitoring sites and other requirements to be discussed
in the State PM monitoring plan. Finally, section 2.8.3 is added to
describe the selection of monitoring locations and SAZ's within the
monitoring planning area. A series of diagrams are used to illustrate
the basic principles.

The PM<INF>2.5 NAMS shall be selected from the core PM<INF>2.5
SLAMS. This network will focus on population-oriented surveillance and
is intended to provide a national trends network to study the impact of
PM<INF>2.5 emission sources including regional transport. A new Table
5, which lists the goals for the number of PM<INF>2.5 NAMS by EPA
Region, is added to Section 3.7. Table 5 in Section 5 is redesignated
as Table 6 and revised to include PM<INF>2.5.
In Section 2.8.1, in particular, MPA's and SAZ's are introduced to
conform to the population-oriented, spatial averaging approach taken in
the proposed new PM<INF>2.5 NAAQS under 40 CFR Part 50. This approach
is more directly related to the epidemiological studies used as the
basis for the proposed revisions to the particulate matter NAAQS. This
proposal recognizes that the use of MPA's and SAZ's introduces greater
complexity into the network design process and the assessment of
violations of the NAAQS. Thus, the Administrator would specifically
welcome comments on the

[[Page 65791]]

network design approach described in Section 2.8.1 through Section
2.8.3.

Previous requirements for number of monitors in this appendix have
been related to the urbanized area populations. The boundaries for the
urbanized populations to do not follow political or geographical
boundaries. Hence, it is difficult at times to determine the component
populations, emissions, or location of monitoring sites. A new concept
is being introduced with this proposal to change from urbanized area
population to MSA/PMSA populations for PM<INF>10 and PM<INF>2.5. This
will make it easier to track monitors for the above reasons, and to
more accurately relate measured concentrations to population exposures.

NAAQS Comparison Sites and New Site Codes
Through its monitoring plan, which is reviewed and approved by the
Regional Administrator, a State would select the population-oriented
2 sites eligible for NAAQS comparisons which are included in each
monitoring planning area and its SAZ's. Comparisons with the annual
primary PM<INF>2.5 NAAQS would be based on population oriented SLAMS
sites as well as other sites representative of area-wide concentrations
in SAZ's. Comparisons to the 24-hour primary PM<INF>2.5 NAAQS would be
based on these sites as well as all other sites which are populationoriented.
To encourage PM<INF>2.5 monitoring initially, for the first 3
years after effective date of promulgation a moratorium is proposed on
using data from all eligible SPM's to determine violations of the
NAAQS. After this time, any operating SPM site which records a
violation of the NAAQS would become eligible for NAAQS comparisons,
should be included in the State monitoring plan, and should be
considered during the State's review and development of their
monitoring network.

\2\ As currently used in Part 58, population-oriented monitoring
or sites applies to residential areas, commercial areas,
recreational areas, industrial areas where workers from more than
one company are located, and other areas where a substantial number
of people may spend a significant fraction of their day.

Figure 1 in Appendix D shows a conceptual Venn diagram that
illustrates which PM<INF>2.5 sites in a MPA would be eligible for
comparison to the 24-hour and annual PM<INF>2.5 NAAQS. To be eligible
for NAAQS comparisons, sites must meet all three of the following
requirements: (1) Are NAMS/SLAMS or other population oriented sites,
(2) are included in the monitoring plan, and (3) meet the requirements
of 58.13 and Appendices A, C, and E. Sites that meet the additional
requirement of generally representing areawide concentrations in the
SAZ are also eligible for comparison to the annual PM<INF>2.5 NAAQS
using the spatial averaging procedure specified in Part 50 Appendix K.
Such sites are designated ``B''. All core monitoring sites and NAMS
sites, which are a subset of the core sites, are B sites as are many
other SLAMS and some non-SLAMS sites. Other population-oriented sites
which are more representative of localized hot spots are only eligible
for comparison on a site-by-site basis to the 24-hour PM<INF>2.5 NAAQS
and are designated ``D''. These may include population-oriented
industrial monitors which meet the applicable Part 58 requirements and
are also included in the PM monitoring plan. The figure shows that all
PM<INF>2.5 SLAMS sites are designated ``B'' or ``D''. Sites not
designated as ``B'' or ``D'' sites would be designated as ``O'' sites.
These codes would become new pollutant specific codes on the AIRS
monitoring site file. In addition, core SLAMS PM<INF>2.5 sites will
receive a new AIRS site type code. These data reporting changes will be
described more fully in future AIRS guidance.
A network design issue that relates to the spatial averaging form
of the annual standard is the selection of the first (and/or only) site
in a prospective SAZ. Because the intent of the spatial average form of
the PM<INF>2.5 NAAQS is to estimate community, area-wide air pollution,
the emphasis on the first selected SLAMS sites (including core SLAMS)
would be ``typical population exposure.''
2. Monitoring Planning Areas and SAZ's

In order to acquire population-oriented, spatially averaged
monitoring data that correspond more closely to the data that are the
basis for the proposed PM<INF>2.5 NAAQS, the concepts of monitoring
planning areas and SAZ's are used in Section 2.8.1. As part of its
monitoring plan, a State will propose monitoring planning areas and
also propose non-overlapping SAZ's for each monitoring planning area.
The number of monitoring planning areas is determined by the State.
This may be one area to cover a small State like Rhode Island or be as
many as 25 to correspond to existing air pollution control districts in
a State like California. Information to be considered includes
topography, PM emissions, number and type of significant PM sources as
well as population density and distribution. Monitoring planning areas
are required to include all metropolitan statistical areas (MSA's) and
Primary Metropolitan Statistical areas (PMSA's) with population greater
than 500,000, and generally recommended to include MSA's/PMSA's with
population greater than 250,000 and high pollution (defined as
producing measurements greater than or equal to 0.8 times the level of
the PM<INF>2.5 NAAQS) as well as other areas determined to be likely to
have high concentration of PM<INF>2.5. In addition, optional MPA's may
include other designated parts of a State. An MPA should not include
different areas separated by topographical barriers. Each MPA can have
one or more SAZ's representing the area. The SAZ define the area within
which all eligible monitoring data (from ``B'' sites) will be averaged
for comparisons with the annual PM<INF>2.5 NAAQS. The MPA's and SAZ's
would be reviewed and approved annually by the Regional Administrator.
Until the monitoring plan is approved, EPA intends to have the SLAMS
and sites eligible for NAAQS comparisons default to the SLAMS
previously approved. Sites which have discontinued monitoring would
continue to be used for comparisons to the NAAQS until their monitoring
type status changes.

Multiple zones within an MPA are most appropriate for large
metropolitan areas, large geographical monitoring regions and areas in
which concentrated source regions are in low population portions of an
MPA. All MPA's and SAZ's must be defined on the basis of some existing
delineated mapping data such as county boundaries, zip codes, census
blocks or groups of census blocks. This will assist in the proper
characterization of the spatial representativeness of air monitoring
sites and facilitate better presentations of air monitoring data on
national, regional, and local maps.

All areas in the ambient air may become a SAZ based on
considerations of population density, pollution concentration gradients
and or the physical size of the area. Generally, a SAZ should
characterize an area of relatively homogeneous air quality (i.e., the
annual average concentration of the individual monitoring locations
within the area should be within <plus-minus>20 percent of the spatial
average) and be affected by the same major source categories of
particulate matter. In MSA's, the SAZ's must completely cover the
entire MPA. In other MPA's, the SAZ's might not completely cover the
entire MPA. For example, small networks consisting of say one or two
monitoring sites may not adequately characterize the air quality in a
large geographic area or in large areas of relatively low population or
pollution density. In another situation,

[[Page 65792]]

population centers and pollution regions represented by monitoring
sites may be geographically disjoint. In these cases, the spatial
representativeness of the monitoring site should be considered in
defining the SAZ boundaries. Until more monitoring sites are
established, the monitored air quality in areas outside of SAZ's is not
known. Although ideally all areas of a State should be included in a
SAZ, monitoring density may be insufficient to completely characterize
a specific MPA and more monitors would be needed. Nonetheless, in some
circumstances a SAZ can be represented by a single monitoring location
and this may be sufficient to properly characterize an MPA. The SAZ's
should generally include a minimum population of 250,000 and not more
than 2 million. Deviations from this criteria should be based on the
area's physical size and population density.
The Administrator recognizes that the designation of SAZ's within
Monitoring Planning Areas introduces a certain degree of complexity
into the monitoring network planning and data usage process. Comments
are therefore solicited on the use of a simpler approach to satisfy the
requirements for spatial averaging which are proposed in Part 50. In
particular, comments are solicited on a approach wherein there is only
one SAZ in each MPA which has the same boundaries as the MPA.
3. Core Monitoring Sites

To provide a minimal PM<INF>2.5 network in all high population
areas for protection of the annual and 24-hour PM NAAQS, each required
monitoring planning area must have at least two core monitors. The new
core monitoring locations would be an important part of the basic PMfine
SLAMS regulatory network. These sites are intended to primarily
reflect community-wide air pollution, which would reflect monitoring
locations in residential areas or where people spend a substantial part
of the day take. In addition to the population-oriented monitoring
sites, core monitors would also be established for background and
transport monitoring. States should work cooperatively in establishing
their State networks in order to maximize the value of monitoring data
to best understand the regional behavior of PM<INF>2.5.
To permit interface with measurements of ozone precursors which are
also contributors to PM<INF>2.5, an additional core monitor collocated
at a PAMS site is required in those MSA's where both PAMS and
PM<INF>2.5 monitoring are required. The core monitor to be collocated
at a PAMS site is considered part of the MPA PM<INF>2.5 SLAMS network
and is not considered as a part of the PAMS network as described in
Section 4 of Appendix D.

The new core population-oriented PM-fine network is conceptually
similar to the existing NAMS for other pollutants, but would allow for
some year to year changes in site location to ensure that the typical
areas of high pollution, high population areas are always monitored.
Core sites will be the key sampling locations designated for initial
monitoring, and a subset would be selected for longer-term monitoring.
The latter would become the NAMS.

The core sites will also produce the most complete data in the PMfine
network. Daily sampling would be required, except during low
pollution seasons or other periods as exempted by EPA. As such, a
subset of these sites should be considered as candidate locations for
adding state-of-the-art research monitoring devices whose data might
need to be considered in future reviews of the PM NAAQS. This will
ensure continuity and comparability of past, present and future PM data
bases.

Finally, because the core sites would produce the most data, many
would be the most likely locations for determining violations of a
short-term NAAQS. The core locations would become critical for judging
future attainment in an area that has been determined to violate the
NAAQS, again putting emphasis on areas with the largest population
impact. Complete data at background and transport core sites will also
provide the needed data base to better understand the source-receptor
relationships and assist the implementation program.
Each SAZ in a required MPA must have at least one core monitor; the
SAZ's in optional MPA's should have at least one core monitor; and it
is also suggested that SAZ's should have at least one core site for
every four SLAMS. Exemptions are allowed for required core stations in
MSA's with population greater than 500,000, if measured or modeled
concentrations of PM<INF>2.5 are less than 80 percent of the NAAQS for
PM<INF>2.5. Specific comments on the required and suggested number of
core monitoring locations are requested.
4. Examples of MPA's, SAZ's and NAAQS Eligible Monitors
Some examples may better illustrate how the concepts of monitoring
planning areas and SAZ's may be realized in practice. The San Joaquin
Valley air basin in California could be an MPA. If emission sources are
distributed throughout this region, then the entire MPA could also be
the SAZ. For large counties, such as California's San Bernardino
County, which have non-uniform emission sources and population density,
there could be at least two SAZ's, such as an eastern SAZ and a western
SAZ which is part of the South Coast Air Basin. For an MSA, such as the
Philadelphia MSA, or MSA/MPA which crosses State boundaries, separate
SAZ's are suggested for each State portion, with substantial population
(e.g. greater than 250,000). For the Philadelphia PA-NJ MSA, this could
mean at least separate zones for the Philadelphia, PA and NJ portions.
In this manner, each State would be responsible for the networks in its
SAZ portion of the MPA. (Each of these SAZ's must have at least one
core monitor for a total of two for the MPA). Furthermore, for MSA's
and large geographic areas with concentrated source regions or
industrial areas, such as Philadelphia, separate SAZ's are suggested
for the residential/city center and the industrial area to better
characterize the gradients in PM<INF>2.5 concentrations. Downtown
street canyons may be appropriate SAZ's if they also include
residential areas, such as is the case in mid-town Manhattan, NY or if
they include commercial areas which have higher PM<INF>2.5
concentrations within the MPA and where significant numbers of people
work during the day. Comments are solicited on criteria for defining
SAZ's.

A series of figures is presented to illustrate the concept of MPA's
and SAZ's. A hypothetical MPA representing an Eastern urban area is
given in Figure 2 of appendix D and illustrates how monitors can be
located in relation to population and areas of poor quality. Figure 3
in Appendix D shows the same MPA as Figure 2, but includes three SAZ's:
an industrial zone, a downtown central business district, and
residential areas. Figure 4 in Appendix D shows the same MPA
illustrated in Figures 2 and 3. However, sites are denoted by whether
they are eligible for comparison with the 24-hour PM<INF>2.5 NAAQS or
both the 24-hour and the annual PM<INF>2.5 NAAQS. Figure 5 in Appendix
D shows potential SAZ's in a hypothetical Western State. Figure 6 in
Appendix D illustrates State coverage by SAZ's both within and outside
MPA's. More detailed guidance for network design for PM<INF>2.5 using
the concepts of core monitoring stations, MPA's, and SAZ's will be
available shortly in an EPA guidance document which is in preparation.

[[Page 65793]]

5. Substitute PM Samplers

Appendix C (Section 2.2) to Part 58 describes conditions under
which TSP samplers may be used as substitutes for PM<INF>10 samplers
and when such TSP samplers must be replaced with PM<INF>10 samplers.
The proposed rule will describe similar language regarding PM<INF>10
samplers which may be used as substitutes for PM<INF>2.5 and provide
clarification to ensure that only the appropriate TSP or PM<INF>10
sites are required to be converted to PM<INF>10 and PM<INF>2.5,
respectively. This provision is intended to be used when PM
concentrations are low and substitute samplers can be used to satisfy
the minimum number of PM samplers needed for an adequate PM network.
This may be most appropriate when sufficient resources to purchase new
PM samplers may not exist and existing samplers can be temporarily used
to serve a new PM network.

6. NAMS Network Design

In Section 3.7, the PM<INF>10 design criteria for NAMS, namely
monitoring objectives, spatial representativeness, the category ``a''
maximum concentration site, number of sites, etc., remains in effect.
In addition, the traditional concept of NAMS as long-term monitoring
stations to assess trends and to support national assessments and
decisions is reiterated. However, concerning PM<INF>2.5 network design,
a more flexible approach is proposed. First, the PM<INF>2.5 NAMS will
be concentrated in metropolitan areas in keeping with the risk
management approach of the proposed new PM<INF>2.5 NAAQS. Next, a
numeric range of prospective PM<INF>2.5 NAMS by EPA Region are
identified. These are based on consideration of a number of factors set
by Regions to provide maximum flexibility for State and local agencies,
but should represent the range of conditions occurring in the Regions
taking into consideration such factors as the total number and types of
sources, ambient characteristics of particulate matter, regional
transport, geographic area, and affected population. The goals for
Regions varies from a low of 10 to 15 for Regions VII, VIII and X to a
high of 35 to 50 for Regions IV and V while the total ranges from 205
to 295 with an expected national target of 250. In particular, comments
are requested about the general approach of goals by Region and the
numbers estimated.

P. Appendix E

Today's revision to Appendix E consists of relatively minor changes
to Section 8 which currently provides the sampler siting criteria for
PM<INF>10. The modifications basically expand the siting requirements
to include PM<INF>2.5 as well as PM<INF>10 by selectively replacing the
term PM<INF>10 with PM which would be defined as applying to PM<INF>10
and PM<INF>2.5. This will permit existing PM<INF>10 sites to continue
to be used and, when appropriate, to serve as platforms for new
PM<INF>2.5 sampling.

Q. Appendix F

A new section has been added for the annual summary statistics for
PM<INF>2.5 in Appendix F. It should be noted that the current
procedures for reporting and certifying the air quality data may be
changed later, since the AIRS system is undergoing reengineering.

R. Cost Estimates for New PM Networks

The costs associated with the start-up of a PM<INF>2.5 network and
the phase-down of the existing PM<INF>10 sampling network depend on the
3-year phase-in of the new proposed requirements and the number of PM
monitors that the Administrator believes are necessary in a mature
network.

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

Table 1. PM-2.5 Network Costs
[Thousands of dollars]

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

Number of Number of Capital Sampling Filter Special Total

Year sites samplers cost & QA analysis studies cost
------------------------------------------------\1\--------------------------------\2\--------------------------
1997........................... 0 0 $4,095 ......... ........... ......... $4,095
1998........................... 216 318 7,908 $4,382 $1,558 $2,600 16,478
1999........................... 714 1,004 6,850 11,514 926 1,300 20,590
2000........................... 1,200 1,490 ......... 17,833 926 1,300 20,059

\1\ The PM-2.5 Network includes 160 collocated monitors for QA purposes, and 130 collocated monitors to avoid

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

weekend site visits.

\2\ Three different types of filter analyses are anticipated (exceedances analyses, screening analyses, and

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

detailed analyses).

Table 2.--Cost for PM<INF>2.5 Filter Analyses

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

Estimated
Type of filter analysis cost per
sample

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

Exceedance Analysis: $200

High PM<INF>2.5 concentration events are optically analyzed
for particle size and composition utilizing electron
microscopy..............................................

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

Screening Analysis:

X-Ray Fluorescence (XRF) for elemental composition
(crustal material, sulfur, and heavy metals)............ 50
Thermo-optical analysis for elemental/organic/total
carbon.................................................. 50

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

Detailed Analysis:

Inductively Coupled Argon Plasma (ICAP) Analysis for
elemental composition................................... 100
Analysis for speciated organic composition............... 400
Analysis for sulfate, aerosol acidity.................... 100

Table 3 presents the change in PM<INF>10 network costs. The costs
are shown for a current network of 1,650 sites and the phase down to a
future projected network of 600 sites. PM<INF>10 costs have been
calculated for the continued operation on a one in 6-day schedule, and
for the relocation or discontinuance of monitoring sites. Table 4 shows
the cost of PM monitoring according to sampling frequency and the type
of PM monitor. Details of this information can be found in the
``Information Collection Request'' for these proposed requirements.

[[Page 65794]]

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

Table3.--PM-10 Network Costs
[Thousands of dollars]

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

Capital
Number of Number of cost to Operation & Total
Year sites samplers\1\ remove maintenance cost
sites cost

1997................................................. 1,650 1,810 ......... $15,474 $15,473
1998................................................. 1,374 1,544 $110 12,181 12,291
1999................................................. 972 1,132 174 8,914 9,088
2000................................ 600 760 161 5,966 6,127

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

\1\ The PM<INF>10 network includes 160 collocated monitors for QA purposes.

Table 4.--Costs for Particulate Monitoring

PM monitor and sampling One-time capital Annual operation &

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

frequency cost maintenance cost

PM-10 1-in-6 day sampling $14,500............ $8,700.

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

schedule.

PM-2.5 1-in-6 day sampling $9,600 to $16,900.. $11,200.

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

schedule.

PM-2.5 every day sampling...... $14,600 to $21,900. $18,900.
Nephelometer (continuous)...... $20,100 to $26,300. $16,700 to

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

$17,500.

S. Reference

Information Collection Request, 40 CFR 58 Ambient Air Quality
Surveillance, OMB #2060-0084, EPA ICR #0940.14, U.S. Environmental
Protection Agency, Office of Air Quality Planning and Standards,
Research Triangle Park, NC 27711 (October 23, 1996).

V. Administrative Requirements

A. Regulatory Impact Analysis

Under Executive Order 12866 (58 FR 51735, October 4, 1993), the
Agency must determine whether the regulatory action is ``significant''
and therefore subject to Office of Management and Budget (OMB) review
and to the requirements of the Executive Order. The Order defines
``significant regulatory action'' as one that is likely to result in a
rule that may:

(1) Have an annual effect on the economy of $100 million or more or
adversely affect in a material way the economy, a sector of the
economy, productivity, competition, jobs, the environment, public
health or safety, or State, local, or governments or communities;
(2) Create a serious inconsistency or otherwise interfere with an
action taken or planned by another Agency;
(3) Materially alter the budgetary impact of entitlements, grants,
user fees, or loan programs or the rights and obligations or recipients
thereof; or

(4) Raise novel legal or policy issues arising out of legal
mandates, the President's priorities, or the principles set forth in
the Executive Order.

It has been determined that this rule is not a ``significant
regulatory action'' under the terms of the Executive Order 12866 and is
therefore not subject to formal OMB review. However, this rule is being
reviewed by OMB under Reporting and Record keeping Requirements (see
below).

B. Paperwork Reduction Act

The information collection requirements contained in this proposed
rule have been submitted for approval to OMB under the Paperwork
Reduction Act, 44 U.S.C. 3501 et seq. An Information Collection Request
document has been prepared by the EPA (ICR No. 0940.14) and a copy may
be obtained from Sandy Farmer, Information Policy Branch, EPA, 401 M
Street SW, Mail Code 2137, Washington, DC 20460; or by calling (202)
260-2740.

Need and Use of the Collection

The main use for the collection of the data is to support the PM
NAAQS revisions. The various parameters reported as part of this ICR
are necessary to ensure that the information and data collected by
State and local agencies to assess the nation's air quality are
defensible, of known quality, and meet the EPA's data quality goals of
completeness, precision, and accuracy.

The need and authority for this information collection is contained
in Section 110(a)(2)(C) of the Act, which requires ambient air quality
monitoring for purposes of the SIP and reporting of the data to EPA,
and Section 319, which requires the reporting of a daily air pollution
index. The legal authority for this requirement is the Ambient Air
Quality Surveillance Regulations, 40 CFR 58.20, 58.21, 58.25, 58.26,
58.28, 58.30, 58.31, 58.35, and 58.36.

The EPA's Office of Air Quality Planning and Standards uses ambient
air monitoring data for a wide variety of purposes, including making
NAAQS attainment/nonattainment decisions; determining the effectiveness
of air pollution control programs; evaluating the effects of air
pollution levels on public health; tracking the progress of SIP's;
providing dispersion modeling support; developing responsible, costeffective
control strategies; reconciling emission inventories; and
developing air quality trends. The collection of PM<INF>2.5 data is
necessary to support the PM<INF>2.5 NAAQS, and the information
collected will have practical utility as a data analysis tool.
The State and local agencies with responsibility for reporting
ambient air quality data and information as requested by these proposed
regulations will submit these data electronically to the U.S. EPA's
Aerometric Information Retrieval System, Air Quality Subsystem (AIRSAQS).
Quality assurance/quality control records and monitoring network
documentation are also maintained by each State/local agency, in AIRSAQS
electronic format where possible.

Reporting and Recordkeeping Burden
The total annual collection and reporting burden associated with
this proposal is estimated to be 490,526 hours. Of this total, 484,545
hours are estimated to be for data reporting, or an average of 3,327
hours for the estimated 130 respondents. The remainder of 5,981 hours
for recordkeeping burden averages 46 hours for the estimated 130
respondents. The capital O/M costs associated with this proposal are
estimated to be $19,714,453. These estimates include time for reviewing
instructions, searching existing data sources, gathering and
maintaining the data needed, and completing and reviewing the
collection of information.

The frequency of data reporting for the NAMS and the SLAMS air
quality data as well as the associated precision and accuracy data are
submitted to EPA according to the schedule defined in 40 CFR part 58.
This regulation currently requires that State and local air quality

[[Page 65795]]

management agencies report their data within 90 days after the end of
the quarter during which the data were collected. The annual SLAMS
report is submitted by July 1 of each year for data collected from
January 1 through December 31 of the previous year in accordance with
40 CFR 58.26. This certification also implies that all SPM data to be
used for regulatory purposes by the affected State or local air quality
management agency have been submitted by July 1.
3. Burden

Burden means the total time, effort, or financial resources
expended by persons to generate, maintain, retain, or disclose or
provide information to or for a Federal agency. This includes the time
needed to review instructions; develop, acquire, install, and utilize
technology and systems for the purpose of collecting, validating, and
verifying information, processing and maintaining information, and
disclosing and providing information; adjust the existing ways to
comply with any previously applicable instructions and requirements;
train personnel to be able to respond to a collection of information;
search data sources; complete and review the collection of information;
and transmit or otherwise disclose the information.
An Agency may not conduct or sponsor, and a person is not required
to respond to a collection of information unless it displays a
currently valid OMB control number. The OMB control numbers for EPA's
regulations are listed in 40 CFR Part 9 and 48 CFR Chapter 15.
Comments are requested on the Agency's need for this information,
the accuracy of the provided burden estimates, and any suggested
methods for minimizing respondent burden, including through the use of
automated collection techniques. Send comments on the ICR to the
Director, OPPE Regulatory Information Division; U.S. Environmental
Protection Agency (2137); 401 M St., SW.; Washington, DC 20460; and to
the Office of Information and Regulatory Affairs, Office of Management
and Budget, 725 17th St., NW., Washington, DC 20503, marked
``Attention: Desk Officer for EPA.'' Include the ICR number in any
correspondence. Since OMB is required to make a decision concerning the
ICR between 30 and 60 days after December 13, 1996, a comment to OMB is
best assured of having its full effect if OMB receives it by January
13, 1997. The final rule will respond to any OMB or public comments on
the information collection requirements contained in this proposal.

C. Impact on Small Entities

Pursuant to section 605(b) of the Regulatory Flexibility Act, 5
U.S.C. 605(b), the Administrator certifies that this rule will not have
a significant economic impact on a substantial number of small
entities. This rulemaking package does not impose any additional
requirements on small entities because it applies to governments whose
jurisdictions cover more than 200,000 population. Under the Regulatory
Flexibility Act, governments are small entities only if they have
jurisdictions of less than 50,000 people. In addition, this rule
imposes no enforceable duties on small businesses.

D. Unfunded Mandates Reform Act of 1995

Under sections 202, 203 and 205 of the Unfunded Mandates Reform Act
of 1995 (``Unfunded Mandates Act''), signed into law on March 22, 1995,
the EPA must undertake various actions in association with proposed or
final rules that include a Federal mandate that may result in estimated
costs of $100 million or more to the private sector, or to State or
local governments in the aggregate.

The EPA has determined that this rule does not contain a Federal
mandate that may result in expenditures of $100 million or more for
State, and local governments, in the aggregate, or the private sector
in any one year. Our economic analysis indicates that the total
implementation cost will be approximately $88,728,000 in 1996 dollars
for the 3 years to phase in the network, or an average of $29,576,000
for the 3-year implementation. The table below shows how this 3-year
average was derived for the various cost elements of monitoring. While
this table represents the 3-year period 1998-2000, the total cost for
PM<INF>2.5 monitoring include the initial capital costs anticipated in
1997. In addition, this rule imposes no enforceable duties on small
businesses.

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

Cost Based on 3-Year Average
[Thousands of dollars]

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

3 year

Cost/Element PM<INF>10 PM<INF>2.5 totals

Network design......................... $0 $571 $571
Site installation...................... 311 5,013 5,324
Sampling & analysis.................... 2,647 6,758 9,405
Maintenance............................ 1,233 1,928 3,161
Data management........................ 1,245 1,574 2,819
Quality assurance...................... 1,745 3,373 5,118
Supervision............................ 1,988 1,189 3,177

Summary \1\........................ 9,169 20,407 29,576

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

\1\ Totals are rounded.

List of Subjects

40 CFR Part 53

Environmental protection, Administrative practice and procedure,
Air pollution control, Reporting and recordkeeping requirements.

40 CFR Part 58

Air pollution control, Intergovernmental relations, Reporting and
recordkeeping requirements.

Dated: November 27, 1996.

Carol M. Browner,

Administrator.

For the reasons set forth in the preamble, title 40, chapter I,
part 53 and part 58 of the Code of Federal Regulations are proposed to
be amended as follows:

[[Page 65796]]

PART 53--[AMENDED]

The authority citation for part 53 continues to read as follows:

Authority: Sec. 301(a) of the Clean Air Act (42 U.S.C. Sec.
1857g(a)) as amended by sec. 15(c)(2) of Pub. L. 91-604, 84 Stat.
1713, unless otherwise noted.

2. Subpart A is revised to read as follows:

Subpart A--General Provisions

Sec.

53.1 Definitions.

53.2 General requirements for a reference method determination.
53.3 General requirements for an equivalent method determination.
53.4 Applications for reference or equivalent method determinations.
53.5 Processing of applications.

53.6 Right to witness conduct of tests.
53.7 Testing of methods at the initiative of the Administrator.
53.8 Designation of reference and equivalent methods.
53.9 Conditions of designation.

53.10 Appeal from rejection of application.
53.11 Cancellation of reference or equivalent method designation.
53.12 Request for hearing on cancellation.
53.13 Hearings.

53.14 Modification of a reference or equivalent method.
53.15 Trade secrets and confidential or privileged information.
53.16 Supersession of reference methods.

Tables to Subpart A of Part 53

Table A-1--Summary of Applicable Requirements for Reference &
Equivalent Methods for Air Monitoring of Criteria Pollutants

Appendix A to Subpart A of Part 53--References

Subpart A--General Provisions

Sec. 53.1 Definitions.

(a) Terms used but not defined in this part shall have the meaning
given them by the Act.

(b) Act means the Clean Air Act (42 U.S.C. 1857-1857l), as amended.
(c) Agency means the Environmental Protection Agency.
(d) Administrator means the Administrator of the Environmental
Protection Agency or the Administrator's authorized representative.
(e) Reference method means a method of sampling and analyzing the
ambient air for an air pollutant that is specified as a reference
method in an appendix to part 50 of this chapter, or a method that has
been designated as a reference method in accordance with this part; it
does not include a method for which a reference method designation has
been canceled in accordance with Sec. 53.11 or Sec. 53.16.
(f) Equivalent method means a method of sampling and analyzing the
ambient air for an air pollutant that has been designated as an
equivalent method in accordance with this part; it does not include a
method for which an equivalent method designation has been canceled in
accordance with Sec. 53.11 or Sec. 53.16.
(g) Candidate method means a method of sampling and analyzing the
ambient air for an air pollutant for which an application for a
reference method determination or an equivalent method determination is
submitted in accordance with Sec. 53.4, or a method tested at the
initiative of the Administrator in accordance with Sec. 53.7.
(h) Manual method means a method for measuring concentrations of an
ambient air pollutant in which sample collection, analysis, or
measurement, or some combination thereof, is performed manually. A
method for PM<INF>10 or PM<INF>2.5 which utilizes a sampler that
requires manual preparation, loading, and weighing of filter samples is
considered a manual method even though the sampler may be capable of
automatically collecting a series of sequential samples.
(i) Automated method or analyzer means a method for measuring
concentrations of an ambient air pollutant in which sample collection
(if necessary), analysis, and measurement are performed automatically
by an instrument.

(j) Test analyzer means an analyzer subjected to testing as part of
a candidate method in accordance with subparts B, C, D, E, or F of this
part, as applicable.

(k) Applicant means a person or entity who submits an application
for a reference or equivalent method determination under Sec. 53.4, or
a person or entity who assumes the rights and obligations of an
applicant under Sec. 53.7. Applicant may include a manufacturer,
distributer, supplier, or vendor.

(l) Ultimate purchaser means the first person who purchases a
reference method or an equivalent method for purposes other than
resale.

(m) PM<INF>10 sampler or PM<INF>2.5 sampler means a device,
associated with a manual method for measuring PM<INF>10 or PM<INF>2.5
(respectively), designed to collect PM<INF>10 or PM<INF>2.5
(respectively) from an ambient air sample, but lacking the ability to
automatically analyze or measure the collected sample to determine the
mass concentration of PM<INF>10 or PM<INF>2.5 in the sampled air.
(n) Test sampler means a PM<INF>10 sampler or a PM<INF>2.5 sampler
subjected to testing as part of a candidate method in accordance with
subparts C, D, E or F of this part.

(o) Collocated describes two or more air samplers, analyzers, or
other instruments which sample the ambient air that are operated
simultaneously while located side by side, separated by a distance that
is large enough to preclude the air sampled by any of the devices from
being affected by any of the other devices, but small enough so that
all devices obtain identical or uniform ambient air samples that are
equally representative of the general area in which the group of
devices is located.

(p) Sequential samples for particulate matter samplers means two or
more particulate matter samples for sequential (but not necessarily
contiguous) time periods that are collected automatically by the same
sampler without the need for intervening operator service.
(q) Class I equivalent method means an equivalent method for
PM<INF>2.5 which is based on a sampler that is very similar to the
sampler specified for reference methods in Appendix L of part 50 of
this chapter, with only minor deviations or modifications, as
determined by the EPA. A common example of a Class I PM<INF>2.5 sampler
is a reference method sampler that has been modified to provide
automatic collection of sequential samples, as defined in paragraph (p)
of this section.

(r) Class II equivalent method means an equivalent method for
PM<INF>2.5 that utilizes a PM<INF>2.5 sampler in which an integrated
PM<INF>2.5 sample is obtained from the atmosphere by filtration and
subjected to a subsequent filter equilibration process followed by a
gravimetric mass determination, but which is not a Class I equivalent
method because of substantial deviations from the design specifications
of the sampler specified for reference methods in Appendix L of part 50
of this chapter, as determined by the EPA.
(s) Class III equivalent method means an equivalent method for
PM<INF>2.5 that has been determined by the EPA not to be a Class I or
Class II equivalent method. This fourth type of PM<INF>2.5 method
includes alternative equivalent method samplers and continuous
analyzers, based on designs and measurement principles different from
those specified for reference methods (e.g., a means for estimating
aerosol mass concentration other than by conventional integrated
filtration followed by equilibration and gravimetric analysis). These
samplers (or monitors) are those deemed to be substantially different
from reference method samplers and may use components and methods other
than

[[Page 65797]]

those specified for reference method samplers. Class III candidate
samplers or analyzers require full equivalency testing and must meet
all requirements specified in subpart F of this chapter.
(t) An ISO-registered facility shall be defined as a manufacturing
facility that is either:

(1) An International Organization for Standardization (ISO) 9001-
registered manufacturing facility, with registration maintained
continuously; or

(2) A facility that can be demonstrated, on the basis of
information submitted to the EPA, to be operated according to an EPAapproved
and periodically audited quality system which meets, to the
extent appropriate, the same general requirements as an ISO registered
facility for the design and manufacture of designated reference and
equivalent method samplers and monitors.
(u) An ISO-certified auditor shall be defined as an auditor either
certified by an ISO accredited registrar or an auditor who, based on
information submitted to the EPA, meets the same general requirements
as provided for ISO-certified auditors.

Sec. 53.2 General requirements for a reference method determination.

The following general requirements for a reference method
determination are summarized in Table A-1 of this subpart.
(a) Manual methods. (1) For measuring SO<INF>2 and lead, Appendices
A and G of part 50 of this chapter specify unique manual reference
methods for those pollutants. Except as provided in Sec. 53.16, other
manual methods for SO<INF>2 and lead will not be considered for
reference method determinations under this part.
(2) A reference method for measuring PM<INF>10 must be a manual
method that meets all requirements specified in Appendix J of part 50
of this chapter and must include a PM<INF>10 sampler that has been
shown in accordance with this part to meet all requirements specified
in subpart D of this part.

(3) A reference method for measuring PM<INF>2.5 must be a manual
method that meets the requirements specified in Appendix L of part 50
of this chapter and must include a PM<INF>2.5 sampler that has been
shown in accordance with this part to meet the applicable requirements
specified in subpart E of this part. Further, reference method samplers
must be manufactured in an ISO 9001-registered facility as defined in
Sec. 53.1(t) and , as set forth in Sec. 53.51 (subpart E, of this
part), and the Product Manufacturing Checklist set forth in subpart E
of this part must be completed by an ISO 9001-certified auditor, as
defined in Sec. 53.1(u), and submitted to the EPA annually to retain a
PM<INF>2.5 reference method designation. In addition, all designated
reference methods for PM<INF>2.5 must meet requirements for network
operating performance determined annually as set forth in section 6 of
Appendix A of part 58 of this chapter.

(b) ``Automated methods.'' An automated reference method for
measuring CO, O<INF>3, and NO<INF>2 must utilize the measurement
principle and calibration procedure specified in the appropriate
appendix to part 50 of this chapter and must have been shown in
accordance with this part to meet the requirements specified in subpart
B of this part.

Sec. 53.3 General requirements for an equivalent method determination.

(a) Manual methods. A manual equivalent method must have been shown
in accordance with this part to satisfy the applicable requirements
specified in subpart C of this part. In addition, PM<INF>10 or
PM<INF>2.5 samplers associated with manual equivalent methods for
PM<INF>10 or PM<INF>2.5 must have been shown in accordance with this
part to satisfy the following additional requirements:
(1) A PM<INF>10 sampler associated with a manual method for
PM<INF>10 must satisfy the requirements of subpart D of this part.
(2) A PM<INF>2.5 Class I equivalent method sampler must satisfy all
requirements of subparts C and E of this part, which include
appropriate demonstration that each and every deviation or modification
from the reference method sampler specifications does not significantly
alter the performance of the sampler.

(3) A PM<INF>2.5 Class II equivalent method sampler must satisfy
the requirements of subparts C, E, and F of this chapter.
(4) Requirements for PM<INF>2.5 Class III equivalent method
samplers are not provided in this part because of the wide range of nofilter
-based measurement technologies that could be applied and the
likelihood that these requirements will have to be specifically adapted
for each such type of technology. Specific requirements will be
developed as needed.

(5) All designated equivalent methods for PM<INF>2.5 must be
manufactured in an ISO 9001-registered facility, as defined in
Sec. 53.1(t) and as set forth in Sec. 53.51 (subpart E) of this part,
and the Product Manufacturing Checklist set forth in Appendix E of this
part must be completed by an ISO 9001-certified auditor, as defined in
Sec. 53.1(u), and submitted to the EPA annually to retain a PM<INF>2.5
equivalent method designation.

(6) All designated equivalent methods for PM<INF>2.5 must also meet
annual requirements for network operating performance determined as set
forth in section 6 of Appendix A of part 58 of this chapter.
(b) Automated methods. (1) Automated equivalent methods for
pollutants other than PM<INF>2.5 or PM<INF>10 must have been shown in
accordance with this part to satisfy the requirements specified in
subparts B and C of this part.

(2) Automated equivalent methods for PM<INF>10 must have been shown
in accordance with this part to satisfy the requirements of subparts C
and D of this part.

(3) Requirements for PM<INF>2.5 Class III automated equivalent
methods for PM<INF>2.5 are not provided in this part because of the
wide range of non-filter-based measurement technologies that could be
applied and the likelihood that these requirements will have to be
specifically adapted for each such type of technology. Specific
requirements will be developed as needed.
(4) All designated equivalent methods for PM<INF>2.5 must be
manufactured in an ISO 9001-registered facility, as set forth in
Appendix E of this part, and the Product Manufacturing Checklist set
forth in Appendix E of this part must be completed by an ISO 9001-
certified auditor and submitted to the EPA annually to retain a
PM<INF>2.5 equivalent method designation.
(5) All designated equivalent methods for PM<INF>2.5 must also meet
annual requirements for network operating performance determined as set
forth in section 6 of Appendix A of part 58 of this chapter.

Sec. 53.4 Applications for reference or equivalent method
determinations.

(a) Applications for reference or equivalent method determinations
shall be submitted in duplicate to: Director, National Exposure
Research Laboratory, Department E (MD-77B), U.S. Environmental
Protection Agency, Research Triangle Park, North Carolina 27711.
(b) Each application shall be signed by an authorized
representative of the applicant, shall be marked in accordance with
Sec. 53.15 (if applicable), and shall contain the following:
(1) A clear identification of the candidate method, which will
distinguish it from all other methods such that the method may be
referred to unambiguously. This identification must consist of a unique
series of descriptors such as title, identification

[[Page 65798]]

number, analyte, measurement principle, manufacturer, brand, model,
etc., as necessary to distinguish the method from all other methods or
method variations, both within and outside the applicant's
organization.

(2) A detailed description of the candidate method, including but
not limited to the following: The measurement principle, manufacturer,
name, model number and other forms of identification, a list of the
significant components, schematic diagrams, design drawings, and a
detailed description of the apparatus and measurement procedures.
Drawings and descriptions pertaining to candidate methods or samplers
for PM<INF>2.5 must meet all applicable requirements in Reference 1 of
Appendix A to this subpart, using appropriate graphical, nomenclature,
and mathematical conventions such as those specified in References 3
and 4 of Appendix A to this subpart.

(3) A copy of a comprehensive operation or instruction manual
providing a complete and detailed description of the operational and
calibration procedures prescribed for field use of the candidate method
and all instruments utilized as part of that method (see Sec. 53.9a).
(i) As a minimum this manual shall include:
(A) Description of the method and associated instruments;
(B) Explanation of all indicators, information displays, and
controls;

(C) Complete setup and installation instructions, including any
additional materials or supplies required;
(D) Details of all initial or startup checks or acceptance tests
and any auxiliary equipment required;

(E) Complete operational instructions;
(F) Calibration procedures and required calibration equipment and
standards;

(G) Instructions for verification of correct or proper operation;
(H) Trouble-shooting guidance and suggested corrective actions for
abnormal operation;

(I) Required or recommended routine, periodic, and preventative
maintenance and maintenance schedules,

(J) Any calculations required to derive final concentration
measurements; and

(K) Appropriate references to 40 CFR part 50, Appendix L, Reference
6, and any other pertinent guidelines.

(ii) The manual shall also include adequate warning of potential
safety hazards that may result from normal use and/or malfunction of
the method and a description of necessary safety precautions. [See
Sec. 53.9(b)] However, the previous requirement shall not be
interpreted to constitute or imply any warranty of safety of the method
by the EPA. For samplers and automated methods, the manual shall
include a clear description of all procedures pertaining to
installation, operation, preventative maintenance, and troubleshooting
and shall also include parts identification diagrams. The manual may be
used to satisfy the requirements of paragraphs (b) (1) and (2) of this
section to the extent that it includes information necessary to meet
those requirements.

(4) A statement that the candidate method has been tested in
accordance with the procedures described in subparts B, C, D, E, and/or
F of this part, as applicable.

(5) Test data, records, calculations, and test results as specified
in subparts B, C, D, E, and/or F of this part, as applicable. Data must
be sufficiently detailed to meet appropriate principles described in
paragraphs 4 through 6 of Reference 2, Part b, sections 3.3.1
(paragraph 1) and 3.5.1 (paragraphs 2 and 3) and in paragraphs 1
through 3 of Reference 5 (section 4.8, Records) of appendix A of this
subpart. Salient requirements from these references include the
following:

(i) The applicant shall maintain and include records of all
relevant measuring equipment, including the make, type, and serial
number or other identification, and most recent calibration with
identification of the measurement standard or standards used and their
NIST traceability. These records shall demonstrate the measurement
capability of each item of measuring equipment used for the application
and include a description and justification (if needed) of the
measurement setup or configuration in which it was used for the tests.
The calibration results shall be recorded and identified in sufficient
detail so that the traceability of all measurements can be determined
and any measurement could be reproduced under conditions close to the
original conditions, if necessary, to resolve any anomalies.
(ii) Test data shall be collected according to the standards of
good practice and by qualified personnel. Test anomalies or
irregularities shall be documented and explained or justified. The
impact and significance of the deviation on test results and
conclusions shall be determined. Data collected shall correspond
directly to the specified test requirement and be labeled and
identified clearly so that results can be verified and evaluated
against the test requirement. Calculations or data manipulations must
be explained in detail so that they can be verified.
(6) A statement that the method, analyzer, or sampler tested in
accordance with this part is representative of the candidate method
described in the application.

(c) For candidate automated methods and candidate manual methods
for PM<INF>10 and PM<INF>2.5, the application shall also contain the
following:

(1) A detailed description of the quality system that will be
utilized, if the candidate method is designated as a reference or
equivalent method, to ensure that all analyzers or samplers offered for
sale under that designation will have essentially the same performance
characteristics as the analyzer(s) or samplers tested in accordance
with this part. In addition, the quality system requirements for
candidate methods for PM<INF>2.5 must be described in sufficient
detail, based on the elements described in section 4 of Reference 1
(Quality System Requirements) of appendix A of this subpart. Further
clarification is provided in the following sections of Reference 2:
Part A (Management Systems), sections 2.2 (Quality System and
Description), 2.3 (Personnel Qualification and Training), 2.4
(Procurement of Items and Services), 2.5 (Documents and Records), and
2.7 (Planning); Part B (Collection and Evaluation of Environmental
Data), sections 3.1 (Planning and Scoping), 3.2 (Design of Data
Collection Operations), and 3.5 (Assessment and Verification of Data
Usability); and Part C (Operation of Environmental Technology),
sections 4.1 (Planning), 4.2 (Design of Systems), and 4.4 (Operation of
Systems) of appendix A of this subpart .
(2) A description of the durability characteristics of such
analyzers or samplers [see Sec. 53.9(c)]. For methods for PM<INF>2.5,
the warranty program must ensure that the required specifications (see
Table A-1 of this subpart) will be met throughout the warranty period
and that the applicant accepts responsibility and liability for
ensuring this conformance, or resolving any nonconformities, including
all necessary components of the system, regardless of the original
manufacturer. The warranty program must be described in sufficient
detail to meet appropriate provisions of the ANSI/ASQC and ISO 9001
standards (References 1 and 2 in appendix A of this subpart) for
controlling conformance and resolving nonconformance, particularly
sections 4.12, 4.13, and 4.14 of Reference 1 in appendix A of this
subpart.

[[Page 65799]]

(i) Section 4.12 in appendix A of this subpart requires the
manufacturer to establish and maintain a system of procedures for
identifying and maintaining the identification of inspection and test
status throughout all phases of manufacturing to ensure that only
instruments that have passed the required inspections and tests are
released for sale.

(ii) Section 4.13 in appendix A of this subpart requires documented
procedures for control of nonconforming product, including review and
acceptable alternatives for disposition; section 4.14 requires
documented procedures for implementing corrective (4.14.2) and
preventive (4.14.3) action to eliminate the causes of actual or
potential nonconformities. In particular, section 4.14.3 requires that
potential causes of nonconformities be eliminated by using information
such as service reports and customer complaints to eliminate potential
causes of nonconformities.

(d) For candidate reference or equivalent methods for PM<INF>2.5,
the applicant shall provide to EPA for test purposes one sampler or
analyzer that is representative of the sampler or analyzer associated
with the candidate method. The sampler or analyzer shall be shipped FOB
destination to Department E, (MD-77B), U.S. EPA, 79 T.W. Alexander
Drive, Research Triangle Park, NC 27709, scheduled to arrive concurrent
with or within 30 days of the arrival of the other application
materials. This analyzer or sampler may be subjected to various tests
that the EPA determines to be necessary or appropriate under
Sec. 53.5(e), and such tests may include special tests not otherwise
described in this part. If the instrument submitted under this
paragraph malfunctions, becomes inoperative, or fails to perform as
represented in the application before the necessary EPA testing is
completed, the applicant shall be afforded an opportunity to repair or
replace the device at no cost to the EPA. Upon completion of the EPA
testing, the analyzer or sampler submitted under this paragraph shall
be repacked by the EPA for return shipment to the applicant, using the
same packing materials used for shipping the instrument to the EPA
unless alternative packing is provided by the applicant. Arrangements
for, and the cost of, return shipment shall be the responsibility of
the applicant. The EPA does not warrant or assume any liability for the
condition of the analyzer or sampler upon return to the applicant.

Sec. 53.5 Processing of applications.

After receiving an application for a reference or equivalent method
determination, the Administrator will publish notice of the application
in the Federal Register and, within 120 calendar days after receipt of
the application, take one or more of the following actions:
(a) Send notice to the applicant, in accordance with Sec. 53.8,
that the candidate method has been determined to be a reference or
equivalent method;

(b) Send notice to the applicant that the application has been
rejected, including a statement of reasons for rejection;
(c) Send notice to the applicant that additional information must
be submitted before a determination can be made and specify the
additional information that is needed (in such cases, the 120-day
period shall commence upon receipt of the additional information);
(d) Send notice to the applicant that additional test data must be
submitted and specify what tests are necessary and how they shall be
interpreted (in such cases, the 120-day period shall commence upon
receipt of the additional test data);

(e) Send notice to the applicant that the application has been
found to be substantially deficient or incomplete and cannot be
processed until additional information is submitted to complete the
application and specify the general areas of substantial deficiency; or
(f) Send notice to the applicant that additional tests will be
conducted by the Administrator, specifying the nature of and reasons
for the additional tests and the estimated time required (in such
cases, the 120-day period shall commence one calendar day after the
additional tests have been completed).

Sec. 53.6 Right to witness conduct of tests.

(a) Submission of an application for a reference or equivalent
method determination shall constitute consent for the Administrator or
the Administrator's authorized representative, upon presentation of
appropriate credentials, to witness or observe any tests required by
this part in connection with the application or in connection with any
modification or intended modification of the method by the applicant.
(b) The applicant shall have the right to witness or observe any
test conducted by the Administrator in connection with the application
or in connection with any modification or intended modification of the
method by the applicant.

(c) Any tests by either party that are to be witnessed or observed
by the other party shall be conducted at a time and place mutually
agreeable to both parties.

Sec. 53.7 Testing of methods at the initiative of the Administrator.

(a) In the absence of an application for a reference or equivalent
method determination, the Administrator may conduct the tests required
by this part for such a determination, may compile such other
information as may be necessary in the judgment of the Administrator to
make such a determination, and on the basis of the tests and
information may determine that a method satisfies applicable
requirements of this part.

(b) In the absence of an application requesting the Administrator
to consider revising an appendix to part 50 of this chapter in
accordance with Sec. 53.16, the Administrator may conduct such tests
and compile such information as may be necessary in the Administrator's
judgment to make a determination under Sec. 53.16(d) and on the basis
of the tests and information make such a determination.
(c) If a method tested in accordance with this section is
designated as a reference or equivalent method in accordance with
Sec. 53.8 or is specified or designated as a reference method in
accordance with Sec. 53.16, any person or entity who offers the method
for sale as a reference or equivalent method thereafter shall assume
the rights and obligations of an applicant for purposes of this part,
with the exception of those pertaining to submission and processing of
applications.

Sec. 53.8 Designation of reference and equivalent methods.

(a) A candidate method determined by the Administrator to satisfy
the applicable requirements of this part shall be designated as a
reference method or equivalent method (as applicable), and a notice of
the designation shall be submitted for publication in the Federal
Register not later than 15 days after the determination is made.
(b) A notice indicating that the method has been determined to be a
reference method or an equivalent method shall be sent to the
applicant. This notice shall constitute proof of the determination
until a notice of designation is published in accordance with paragraph
(a) of this section.

(c) The Administrator will maintain a current list of methods
designated as reference or equivalent methods in accordance with this
part and will send a copy of the list to any person or group

[[Page 65800]]

upon request. A copy of the list will be available for inspection or
copying at EPA Regional Offices.

Sec. 53.9 Conditions of designation.

Designation of a candidate method as a reference method or
equivalent method shall be conditioned on the applicant's compliance
with the following requirements. Failure to comply with any of the
requirements shall constitute a ground for cancellation of the
designation in accordance with Sec. 53.11.
(a) Any method offered for sale as a reference or equivalent method
shall be accompanied by a copy of the manual referred to in
Sec. 53.4(b)(3) when delivered to any ultimate purchaser.
(b) Any method offered for sale as a reference or equivalent method
shall generate no unreasonable hazard to operators or to the
environment during normal use or when malfunctioning.
(c) Any analyzer, PM<INF>10 sampler, or PM<INF>2.5 sampler offered
for sale as a reference or equivalent method shall function within the
limits of the performance specifications referred to in Sec. 53.20(a),
Sec. 53.40(a), Sec. 53.50(a), or Sec. 53.60(a), as applicable, for at
least 1 year after delivery and acceptance when maintained and operated
in accordance with the manual referred to in Sec. 53.4(b)(3).
(d) Any analyzer, PM<INF>10 sampler or PM<INF>2.5 sampler offered
for sale as a reference or equivalent method shall bear a prominent,
permanently affixed label or sticker indicating that the analyzer or
sampler has been designated by EPA as a reference method or as an
equivalent method (as applicable) in accordance with this part and
displaying any designated method identification number that may be
assigned by the EPA.

(e) If an analyzer is offered for sale as a reference or equivalent
method and has one or more selectable ranges, the label or sticker
required by paragraph (d) of this section shall be placed in close
proximity to the range selector and shall indicate clearly which range
or ranges have been designated as parts of the reference or equivalent
method.

(f) An applicant who offers analyzers, PM<INF>10 samplers, or
PM<INF>2.5 samplers for sale as reference or equivalent methods shall
maintain an accurate and current list of the names and mailing
addresses of all ultimate purchasers of such analyzers or samplers. For
a period of 7 years after publication of the reference or equivalent
method designation applicable to such an analyzer or sampler, the
applicant shall notify all ultimate purchasers of the analyzer or
PM<INF>2.5 or PM<INF>10 sampler within 30 days if the designation has
been canceled in accordance with Sec. 53.11 or Sec. 53.16 or if
adjustment of the analyzer or sampler is necessary under Sec. 53.11(b).
(g) If an applicant modifies an analyzer, PM<INF>10 sampler, or
PM<INF>2.5 sampler that has been designated as a reference or
equivalent method, the applicant shall not sell the modified analyzer
or sampler as a reference or equivalent method nor attach a label or
sticker to the modified analyzer or sampler under paragraph (d) or (e)
of this section until the applicant has received notice under
Sec. 53.14(c) that the existing designation or a new designation will
apply to the modified analyzer, PM<INF>10 sampler, or PM<INF>2.5
sampler or has applied for and received notice under Sec. 53.8(b) of a
new reference or equivalent method determination for the modified
analyzer or sampler.

(h) An applicant who has offered PM<INF>2.5 samplers or analyzers
for sale as part of a reference or equivalent method may continue to do
so only so long as the reference or equivalent method meets the annual
requirements for network operating performance determined as set forth
in section 6 of Appendix A of part 58 of this chapter. In the event
that the annual network operating performance does not meet those
requirements, the EPA shall, within 90 days after the end of the
calendar year, notify the applicant of the unacceptable network
performance assessment and issue a preliminary finding and notification
of possible cancellation of the reference or equivalent method
designation under Sec. 53.11. (Net performance is generally assessed
for each calendar year, although when the number of samples for a
specific method is not great enough to determine precision with
adequate confidence, more than 1 calendar year of data may be
combined.)

(i) An applicant who has offered PM<INF>2.5 samplers or analyzers
for sale as part of a reference or equivalent method may continue to do
so only so long as the facility in which the samplers or analyzers are
manufactured continues to be an ISO-registered facility, as set forth
in subpart E of this part. In the event that the ISO registration for
the facility is withdrawn, suspended, or otherwise becomes
inapplicable, either permanently or for some specified time interval,
such that the facility is no longer an ISO-registered facility, the
applicant shall notify EPA within 30 days of the date the facility
becomes other than an ISO-registered facility, and upon such
notification, the EPA shall issue a preliminary finding and
notification of possible cancellation of the reference or equivalent
method designation under Sec. 53.11.

(j) An applicant who has offered PM<INF>2.5 samplers or analyzers
for sale as part of a reference or equivalent method may continue to do
so only so long as updates of the Product Manufacturing Checklist set
forth in subpart E of this part are submitted annually. In the event
that an annual Checklist update is not received by the EPA within 12
months of the date of the last such submitted Checklist or Checklist
update, the EPA shall notify the applicant within 30 days that the
Checklist update has not been received and shall, within 30 days from
the issuance of such notification, issue a preliminary finding and
notification of possible cancellation of the reference or equivalent
method designation under Sec. 53.11.

Sec. 53.10 Appeal from rejection of application.

Any applicant whose application for a reference or equivalent
method determination has been rejected may appeal the Administrator's
decision by taking one or more of the following actions:
(a) The applicant may submit new or additional information in
support of the application.

(b) The applicant may request that the Administrator reconsider the
data and information already submitted.
(c) The applicant may request that any test conducted by the
Administrator that was a material factor in the decision to reject the
application be repeated.

Sec. 53.11 Cancellation of reference or equivalent method designation.

(a) Preliminary finding. If the Administrator makes a preliminary
finding on the basis of any available information that a representative
sample of a method designated as a reference or equivalent method and
offered for sale as such does not fully satisfy the requirements of
this part or that there is any violation of the requirements set forth
in Sec. 53.9, the Administrator may initiate proceedings to cancel the
designation in accordance with the following procedures.
(b) Notification and opportunity to demonstrate or achieve
compliance.

(1) After making a preliminary finding in accordance with paragraph
(a) of this section, the Administrator will send notice of the
preliminary finding to the applicant, together with a statement of the
facts and reasons on which the preliminary finding is based, and will
publish notice of the preliminary finding in the Federal Register.
(2) The applicant will be afforded an opportunity to demonstrate or
to

[[Page 65801]]

achieve compliance with the requirements of this part within 60 days
after publication of notice in accordance with paragraph (b)(1) of this
section or within such further period as the Administrator may allow,
by demonstrating to the satisfaction of the Administrator that the
method in question satisfies the requirements of this part, by
commencing a program to make any adjustments that are necessary to
bring the method into compliance, or by taking such action as may be
necessary to cure any violation of the requirements of Sec. 53.9. If
adjustments are necessary to bring the method into compliance, all such
adjustments shall be made within a reasonable time as determined by the
Administrator. If the applicant demonstrates or achieves compliance in
accordance with this paragraph (b)(2), the Administrator will publish
notice of such demonstration or achievement in the Federal Register.
(c) Request for hearing. Within 60 days after publication of a
notice in accordance with paragraph (b)(1) of this section, the
applicant or any interested person may request a hearing as provided in
Sec. 53.12.

(d) Notice of cancellation. If, at the end of the period referred
to in paragraph (b)(2) of this section, the Administrator determines
that the reference or equivalent method designation should be canceled,
a notice of cancellation will be published in the Federal Register and
the designation will be deleted from the list maintained under
Sec. 53.8(c). If a hearing has been requested and granted in accordance
with Sec. 53.12, action under this paragraph (d) will be taken only
after completion of proceedings (including any administrative review)
conducted in accordance with Sec. 53.13 and only if the decision of the
Administrator reached in such proceedings is that the designation in
question should be canceled.

Sec. 53.12 Request for hearing on cancellation.

Within 60 days after publication of a notice in accordance with
Sec. 53.11(b)(1), the applicant or any interested person may request a
hearing on the Administrator's action. If, after reviewing the request
and supporting data, the Administrator finds that the request raises a
substantial issue of fact, a hearing will be granted in accordance with
Sec. 53.13 with respect to such issue. The request shall be in writing,
signed by an authorized representative of the applicant or interested
person, and shall include a statement specifying:
(a) Any objections to the Administrator's action; and
(b) Data or other information in support of such objections.

Sec. 53.13 Hearings.

(a)(1) After granting a request for a hearing under Sec. 53.12, the
Administrator will designate a presiding officer for the hearing.
(2) If a time and place for the hearing have not been fixed by the
Administrator, the hearing will be held as soon as practicable at a
time and place fixed by the presiding officer, except that the hearing
shall in no case be held sooner than 30 days after publication of a
notice of hearing in the Federal Register.
(3) For purposes of the hearing, the parties shall include the
Environmental Protection Agency, the applicant or interested person(s)
who requested the hearing, and any person permitted to intervene in
accordance with paragraph (c) of this section.
(4) The Deputy General Counsel or the Deputy General Counsel's
representative will represent the Environmental Protection Agency in
any hearing under this section.

(5) Each party other than the Environmental Protection Agency may
be represented by counsel or by any other duly authorized
representative.

(b)(1) Upon appointment, the presiding officer will establish a
hearing file. The file shall contain copies of the notices issued by
the Administrator pursuant to Sec. 53.11(b)(1), together with any
accompanying material, the request for a hearing and supporting data
submitted therewith, the notice of hearing published in accordance with
paragraph (a)(2) of this section, and correspondence and other material
data relevant to the hearing.

(2) The hearing file shall be available for inspection by the
parties or their representatives at the office of the presiding
officer, except to the extent that it contains information identified
in accordance with Sec. 53.15.

(c) The presiding officer may permit any interested person to
intervene in the hearing upon such a showing of interest as the
presiding officer may require; provided that permission to intervene
may be denied in the interest of expediting the hearing where it
appears that the interests of the person seeking to intervene will be
adequately represented by another party (or by other parties),
including the Environmental Protection Agency.
(d)(1) The presiding officer, upon the request of any party or at
the officer's discretion, may arrange for a prehearing conference at a
time and place specified by the officer to consider the following:
(i) Simplification of the issues.

(ii) Stipulations, admissions of fact, and the introduction of
documents.

(iii) Limitation of the number of expert witnesses.
(iv) Possibility of agreement on disposing of all or any of the
issues in dispute.

(v) Such other matters as may aid in the disposition of the
hearing, including such additional tests as may be agreed upon by the
parties.

(2) The results of the conference shall be reduced to writing by
the presiding officer and made part of the record.
(e)(1) Hearings shall be conducted by the presiding officer in an
informal but orderly and expeditious manner. The parties may offer oral
or written evidence, subject to exclusion by the presiding officer of
irrelevant, immaterial, or repetitious evidence.
(2) Witnesses shall be placed under oath.
(3) Any witness may be examined or cross-examined by the presiding
officer, the parties, or their representatives. The presiding officer
may, at his discretion, limit cross-examination to relevant and
material issues.

(4) Hearings shall be reported verbatim. Copies of transcripts of
proceedings may be purchased from the reporter.
(5) All written statements, charts, tabulations, and data offered
in evidence at the hearing shall, upon a showing satisfactory to the
presiding officer of their authenticity, relevancy, and materiality, be
received in evidence and shall constitute part of the record.
(6) Oral argument shall be permitted. The presiding officer may
limit oral presentations to relevant and material issues and designate
the amount of time allowed for oral argument.
(f)(1) The presiding officer shall make an initial decision which
shall include written findings and conclusions and the reasons therefor
on all the material issues of fact, law, or discretion presented on the
record. The findings, conclusions, and written decision shall be
provided to the parties and made part of the record. The initial
decision shall become the decision of the Administrator without further
proceedings unless there is an appeal to, or review on motion of, the
Administrator within 30 calendar days after the initial decision is
filed.

(2) On appeal from or review of the initial decision, the
Administrator will have all the powers consistent with making the
initial decision, including the discretion to require or allow briefs,
oral argument, the taking of additional evidence or the remanding to
the presiding officer for additional proceedings. The decision by the

[[Page 65802]]

Administrator will include written findings and conclusions and the
reasons or basis therefor on all the material issues of fact, law, or
discretion presented on the appeal or considered in the review.

Sec. 53.14 Modification of a reference or equivalent method.

(a) An applicant who offers a method for sale as a reference or
equivalent method shall report to the Administrator prior to
implementation any intended modification of the method, including but
not limited to modifications of design or construction or of
operational and maintenance procedures specified in the operation
manual [see Sec. 53.9(g)]. The report shall be signed by an authorized
representative of the applicant, marked in accordance with Sec. 53.15
(if applicable), and addressed as specified in Sec. 53.4(a).
(b) A report submitted under paragraph (a) of this section shall
include:

(1) A description, in such detail as may be appropriate, of the
intended modification;

(2) A brief statement of the applicant's belief that the
modification will, will not, or may affect the performance
characteristics of the method;

(3) A brief statement of the probable effect if the applicant
believes the modification will or may affect the performance
characteristics of the method; and

(4) Such further information, including test data, as may be
necessary to explain and support any statement required by paragraphs
(b)(2) and (b)(3) of this section.

(c) Within 30 calendar days after receiving a report under
paragraph (a) of this section, the Administrator will take one or more
of the following actions:

(1) Notify the applicant that the designation will continue to
apply to the method if the modification is implemented.
(2) Send notice to the applicant that a new designation will apply
to the method (as modified) if the modification is implemented, submit
notice of the determination for publication in the Federal Register,
and revise or supplement the list referred to in Sec. 53.8(c) to
reflect the determination.

(3) Send notice to the applicant that the designation will not
apply to the method (as modified) if the modification is implemented
and submit notice of the determination for publication in the Federal
Register;

(4) Send notice to the applicant that additional information must
be submitted before a determination can be made and specify the
additional information that is needed (in such cases, the 30-day period
shall commence upon receipt of the additional information);
(5) Send notice to the applicant that additional tests are
necessary and specify what tests are necessary and how they shall be
interpreted (in such cases, the 30-day period shall commence upon
receipt of the additional test data); or
(6) Send notice to the applicant that additional tests will be
conducted by the Administrator and specify the reasons for and the
nature of the additional tests (in such cases, the 30-day period shall
commence one calendar day after the additional tests are completed).
(d) An applicant who has received a notice under paragraph (c)(3)
of this section may appeal the Administrator's action as follows:
(1) The applicant may submit new or additional information
pertinent to the intended modification.
(2) The applicant may request the Administrator to reconsider data
and information already submitted.

(3) The applicant may request that the Administrator repeat any
test conducted that was a material factor in the Administrator's
determination. A representative of the applicant may be present during
the performance of any such retest.

Sec. 53.15 Trade secrets and confidential or privileged information.

Any information submitted under this part that is claimed to be a
trade secret or confidential or privileged information shall be marked
or otherwise clearly identified as such in the submittal. Information
so identified will be treated in accordance with part 2 of this chapter
(concerning public information).

Sec. 53.16 Supersession of reference methods.

(a) This section prescribes procedures and criteria applicable to
requests that the Administrator specify a new reference method, or a
new measurement principle and calibration procedure on which reference
methods shall be based, by revision of the appropriate appendix to 50
part of this chapter. Such action will ordinarily be taken only if the
Administrator determines that a candidate method or a variation thereof
is substantially superior to the existing reference method(s).
(b) In exercising discretion under this section, the Administrator
will consider:

(1) The benefits, in terms of the requirements and purposes of the
Act, that would result from specifying a new reference method or a new
measurement principle and calibration procedure;
(2) The potential economic consequences of such action for State
and local control agencies; and

(3) Any disruption of State and local air quality monitoring
programs that might result from such action.
(c) An applicant who wishes the Administrator to consider revising
an appendix to part 50 of this chapter on the ground that the
applicant's candidate method is substantially superior to the existing
reference method(s) shall submit an application for a reference or
equivalent method determination in accordance with Sec. 53.4 and shall
indicate therein that such consideration is desired. The application
shall include, in addition to the information required by Sec. 53.4,
data and any other information supporting the applicant's claim that
the candidate method is substantially superior to the existing
reference method(s).

(d) After receiving an application under paragraph (c) of this
section, the Administrator will publish notice of its receipt in the
Federal Register and, within 120 calendar days after receipt of the
application, take one of the following actions:
(1) Determine that it is appropriate to propose a revision of the
appendix to part 50 of this chapter in question and send notice of the
determination to the applicant;

(2) Determine that it is inappropriate to propose a revision of the
appendix to part 50 of this chapter in question, determine whether the
candidate method is a reference or equivalent method, and send notice
of the determinations, including a statement of reasons for the
determination not to propose a revision, to the applicant;
(3) Send notice to the applicant that additional information must
be submitted before a determination can be made and specify the
additional information that is needed (in such cases, the 120-day
period shall commence upon receipt of the additional information);
(4) Send notice to the applicant that additional tests are
necessary, specifying what tests are necessary and how they shall be
interpreted (in such cases, the 120-day period shall commence upon
receipt of the additional test data); or
(5) Send notice to the applicant that additional tests will be
conducted by the Administrator, specifying the nature of and reasons
for the additional tests and the estimated time required (in such
cases, the 120-day period shall

[[Page 65803]]

commence one calendar day after the additional tests have been
completed).

(e)(1)(i) After making a determination under paragraph (d)(1) of
this section, the Administrator will publish a notice of proposed
rulemaking in the Federal Register. The notice will indicate that the
Administrator proposes:

(A) To revise the appendix to part 50 of this chapter in question;
(B) Where the appendix specifies a measurement principle and
calibration procedure, to cancel reference method designations based on
the appendix; and

(ii) The notice will include the terms or substance of the proposed
revision, will indicate what period(s) of time the Administrator
proposes to allow for replacement of existing methods under section 2.3
of Appendix C to part 58 of this chapter, and will solicit public
comments on the proposal with particular reference to the
considerations set forth in paragraphs (a) and (b) of this section.
(2) If, after consideration of comments received, the Administrator
determines that the appendix to part 50 in question should be revised,
the Administrator will by publication in the Federal Register
promulgate the proposed revision, with such modifications as may be
appropriate in view of comments received; where the appendix to part 50
(prior to revision) specifies a measurement principle and calibration
procedure, cancel reference method designations based on the appendix;
cancel equivalent method designations based on the existing reference
method(s); and specify the period(s) that will be allowed for
replacement of existing methods under section 2.3 of Appendix C to part
58 of this chapter, with such modifications from the proposed period(s)
as may be appropriate in view of comments received. Canceled
designations will be deleted from the list maintained under
Sec. 53.8(c). The requirements and procedures for cancellation set
forth in Sec. 53.11 shall be inapplicable to cancellation of reference
or equivalent method designations under this section.
(3) If the appendix to part 50 of this chapter in question is
revised to specify a new measurement principle and calibration
procedure on which the applicant's candidate method is based, the
Administrator will take appropriate action under Sec. 53.5 to determine
whether the candidate method is a reference method.
(4) Upon taking action under paragraph (e)(2) of this section, the
Administrator will send notice of the action to all applicants for
whose methods reference and equivalent method designations are canceled
by such action.

(f) An applicant who has received notice of a determination under
paragraph (d)(2) of this section may appeal the determination by taking
one or more of the following actions:

(1) The applicant may submit new or additional information in
support of the application.

(2) The applicant may request that the Administrator reconsider the
data and information already submitted.
(3) The applicant may request that any test conducted by the
Administrator that was a material factor in making the determination be
repeated.

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

Tables to Subpart A of Part 53 Table A-1 to Subpart A--Summary of Applicable Requirements for Reference and Equivalent Methods for Air Monitoring of Criteria Pollutants

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

                                                                                                      Applicable subparts of part 53

Pollutant Ref. or equivalent Manual or automated Applicable part -----------------------------------------------

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

                                                                                          50 appendix      A     B     C     D     E     F

SO<INF>2....... Reference.............. Manual................ A ...... ...... ...... ...... ...... ......

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

                  Equivalent.............  Manual................  .................  <check  ......  <check  ......  ......  ......
                                                                                                              >               >
                  Automated.............  .................  <check  <check  <check  ......  ......  ......
                                                                                                              >       >       >

CO............... Reference.............. Automated............. C <check <check ...... ...... ...... ......

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

                                                                                                              >       >
                 Equivalent.............  Manual................  .................  <check  ......  <check  ......  ......  ......
                                                                                                              >               >
                 Automated.............  .................  <check  <check  <check  ......  ......  ......
                                                                                                              >       >       >

O<INF>3....... Reference.............. Automated............. D <check <check ...... ...... ...... ......

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

                                                                                                              >       >
                Equivalent.............  Manual................  .................  <check  ......  <check  ......  ......  ......
                                                                                                              >               >
                Automated.............  .................  <check  <check  <check  ......  ......  ......
                                                                                                              >       >       >

NO<INF>2.. Reference.............. Automated............. F <check <check ...... ...... ...... ......

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

                                                                                                              >       >
             Equivalent.............  Manual................  .................  <check  ......  <check  ......  ......  ......
                                                                                                              >               >
             Automated.............  .................  <check  <check  <check  ......  ......  ......
                                                                                                              >       >       >

Pb.......... Reference.............. Manual................ G ...... ...... ...... ...... ...... ......

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

            Equivalent.............  Manual................  .................  <check  ......  <check  ......  ......  ......
                                                                                                              >               >

PM<INF>10.. Reference.............. Manual............... J <check ...... ...... <check ...... ......

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

                                                                                                              >         >
              Equivalent.............  Manual................  ..............  <check  ......  <check  <check  ......  ......
                                                                                                              >         >       >
              Automated.............  .................  <check  ......  <check  <check  ......  ......
                                                                                                              >         >       >

PM<INF>2.5... Reference.............. Manual................ L <check .... .... .... <check ....

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

                                                                                                              >                    >
              Equivalent Class I.....  Manual................  L      <check  ......  <check  ......  <check  ......
                                                                                                              >          >          >
              Equivalent Class II....  Manual................  L      <check  ......  <check  ......  <check  <check
                                                                                                              >          >          >       >
             Equivalent Class III...  Manual or Automated...  ..............  <check  ......  <check  ......  <check  <check
                                                                                                          >      > \1\       > \1\   > \1\

\1\ Because of the wide variety of potential devices possible, the specific requirements applicable to a Class III candidate equivalent method for PM<INF>2.5 are not specified explicitly in this part but, instead, shall be determined on a case-by-case basis for each such candidiate method. [[Page 65804]] Appendix A to Subpart A of Part 53--References

American National Standard.Quality Systems-Model for Quality Assurance in Design, Development, Production, Installation, and Servicing, ANSI/ISO/ASQC Q9001-1994. Available from American Society for Quality Control, 611 East Wisconsin Avenue, Milwaukee, WI 53202.
American National Standard--Specifications and Guidelines for Quality Systems for Environmental Data Collection and Environmental Technology Programs, ANSI/ASQC E4.1994. Available from American Society for Quality Control, 611 East Wisconsin Avenue, Milwaukee, WI 53202.
Dimensioning and Tolerancing, ASME Y14.5M-1994. Available from the American Society of Mechanical Engineers, 345 East 47th Street, New York, NY 10017.
Mathematical Definition of Dimensioning and Tolerancing Principles, ASME Y14.5.1M-1994. Available from the American Society of Mechanical Engineers, 345 East 47th Street, New York, NY 10017.
ISO 10012, Quality assurance requirements for measuring equipment.Part 1: Meteorological confirmation system for measuring equipment):1992(E). Available from American Society for Quality Control, 611 East Wisconsin Avenue, Milwaukee, WI 53202.
Quality Assurance Handbook for Air Pollution Measurement Systems, Volume II, Ambient Air Specific Methods (Interim Edition), Section 2.12. EPA/600/R-94/038b, April 1994. Available from CERI, ORD Publications, U.S. Environmental Protection Agency, 26 West Martin Luther King Drive, Cincinnati, Ohio 45268. [Note: Section 2.12 of Volume II is currently under development and will not be available from the CERI address until it is published as an addition to EPA/ 600/R-94/038b. Prepublication draft copies of Section 2.12 will be available from Department E (MD-77B), U. S. EPA, Research Triangle Park, NC 27711 or from the contact identified at the beginning of this proposed rule.]
Subpart C is revised to read as follows: Subpart C--Procedures for Determining Comparability Between Candidate Methods and Reference Methods
Sec.
53.30 General provisions.
53.31 Test conditions.
53.32 Test procedures for methods for SO<INF>2, CO, O<INF>3, and NO<INF>2.
53.33 Test procedure for methods for lead. 53.34 Test procedure for methods for PM<INF>10 and PM<INF>2.5 Tables to Subpart C of Part 53 Table C-1--Test Concentration Ranges, Number of Measurements Required, and Maximum Discrepancy Specification Table C-2--Sequence of Test Measurements Table C-3--Test Specifications for Lead Methods Table C-4--Specifications for PM<INF>10 and PM<INF>2.5 Methods Figures to Subpart C Figure C-1--Suggested Format for Reporting Test Results Appendix A to Subpart C to Part 53--References Subpart C--Procedures for Determining Comparability Between Candidate Methods and Reference Methods Sec. 53.30 General provisions. (a) Determination of comparability. The test procedures prescribed in this Subpart shall be used to determine if a candidate method is comparable to a reference method when both methods measure pollutant concentrations in ambient air.
(1) Comparability is shown for SO<INF>2, CO, O<INF>33, and NO<INF>2 methods when the differences between:
(i) Measurements made by a candidate manual method or by a test analyzer representative of a candidate automated method; and (ii) Measurements made simultaneously by a reference method, are less than or equal to the values specified in the last column of Table C-1 of this subpart.
(2) Comparability is shown for lead methods when the differences between:
(i) Measurements made by a candidate method, and (ii) Measurements made by the reference method on simultaneously collected lead samples (or the same sample, if applicable), are less than or equal to the value specified in Table C-3 of this subpart.
(3) Comparability is shown for PM<INF>10 and PM<INF>2.5 methods when the relationship between:
(i) Measurements made by a candidate method; and (ii) Measurements made by a reference method on simultaneously collected samples (or the same sample, if applicable) at each of two test sites, is such that the linear regression parameters (slope, intercept, and correlation coefficient) describing the relationship meet the values specified in Table C-4 of this subpart. (b) Selection of test sites. (1) All methods. Each test site shall be in a predominately urban area which can be shown to have at least moderate concentrations of various pollutants. The site shall be clearly identified and shall be justified as an appropriate test site with suitable supporting evidence such as maps, population density data, vehicular traffic data, emission inventories, pollutant measurements from previous years, concurrent pollutant measurements, and meteorological data. If approval of a proposed test site is desired prior to conducting the tests, a written request for approval of the test site or sites must be submitted prior to conducting the tests and must include the supporting and justification information required. The Administrator may exercise discretion in selecting a different site (or sites) for any additional tests the Administrator decides to conduct. (2) Methods for SO<INF>2, CO, O<INF>3, and NO<INF>2. All test measurements are to be made at the same test site. If necessary, the concentration of pollutant in the sampled ambient air may be augmented with artificially generated pollutant to facilitate measurements in the specified ranges. [See paragraph (d)(2) of this section.] (3) Methods for lead. Test measurements may be made at any number of test sites. Augmentation of pollutant concentrations is not permitted, hence an appropriate test site or sites must be selected to provide lead concentrations in the specified range. (4) Methods for PM<INF>10. Test measurements must be made, or derived from particulate samples collected, at not less than two test sites, each of which must be located in a geographical area characterized by ambient particulate matter that is significantly different in nature and composition from that at the other test site(s). Augmentation of pollutant concentrations is not permitted, hence appropriate test sites must be selected to provide PM10 concentrations in the specified range. The tests at the two sites may be conducted in different calendar seasons, if appropriate, to provide PM<INF>10 concentrations in the specified ranges. (5) Methods for PM<INF>2.5. Augmentation of pollutant concentrations is not permitted, hence appropriate test sites must be selected to provide PM<INF>2.5 concentrations and PM<INF>2.5/PM<INF>10 ratios (if applicable) in the specified ranges. (i) Where only one test site is required, as specified in Table C-4 of this subpart, the site need only meet the PM<INF>2.5 ambient concentration levels required by Sec. 53.34(c)(3). (ii) Where two sites are required, as specified in Table C-4 of this subpart, each site must be selected to provide the ambient concentration levels required by Sec. 53.34(c)(3). In addition, one site [[Page 65805]] must be selected such that all acceptable test sample sets, as defined in Sec. 53.34(c)(3), have a PM<INF>2.5/PM<INF>10 ratio of more than 0.75; the other site must be selected such that all acceptable test sample sets, as defined in Sec. 53.34(c)(3), have a PM<INF>2.5/ PM<INF>10 ratio of less than 0.40. At least two reference method PM<INF>10 samplers shall be collocated with the candidate and reference method PM<INF>2.5 samplers and operated simultaneously with the other samplers at each test site to measure concurrent ambient concentrations of PM<INF>10 to determine the PM<INF>2.5/PM<INF>10 ratio for each sample set. The PM<INF>2.5/PM<INF>10 ratio for each sample set shall be the average of the PM<INF>2.5 concentration, as determined in Sec. 53.34(c)(1), divided by the average PM<INF>10 concentration, as measured by the PM<INF>10 samplers. The tests at the two sites may be conducted in different calendar seasons, if appropriate, to provide PM<INF>2.5 concentrations and PM<INF>2.5/PM<INF>10 ratios in the specified ranges.
(c) Test atmosphere. Ambient air sampled at an appropriate test site or sites shall be used for these tests. Simultaneous concentration measurements shall be made in each of the concentration ranges specified in Table C-1, C-3, or C-4 of this subpart, as appropriate. (d) Sample collection.
(1) All methods. All test concentration measurements or samples shall be taken in such a way that both the candidate method and the reference method receive air samples that are homogenous or as nearly identical as practical.
(2) Methods for SO<INF>2, CO, O<INF>3, and NO<INF>2. Ambient air shall be sampled from a common intake and distribution manifold designed to deliver homogenous air samples to both methods. Precautions shall be taken in the design and construction of this manifold to minimize the removal of particulates and trace gases, and to insure that identical samples reach the two methods. If necessary, the concentration of pollutant in the sampled ambient air may be augmented with artificially generated pollutant. However, at all times the air sample measured by the candidate and reference methods under test shall consist of not less than 80 percent ambient air by volume. Schematic drawings, physical illustrations, descriptions, and complete details of the manifold system and the augmentation system (if used) shall be submitted.
(3) Methods for lead, PM<INF>10 and PM<INF>2.5. The ambient air intake points of all the candidate and reference method collocated samplers for lead, PM<INF>10 or PM<INF>2.5 shall be positioned at the same height above the ground level, and between 2 and 5 meters apart. The samplers shall be oriented in a manner that will minimize spatial and wind directional effects on sample collection. (4) PM<INF>10 methods employing the same sampling procedure as the reference method but a different analytical method. Candidate methods for PM<INF>10 which employ a sampler and sample collection procedure that are identical to the sampler and sample collection procedure specified in the reference method, but use a different analytical procedure, may be tested by analyzing common samples. The common samples shall be collected according to the sample collection procedure specified by the reference method and shall be analyzed in accordance with the analytical procedures of both the candidate method and the reference method.
(e) Submission of test data and other information. All recorder charts, calibration data, records, test results, procedural descriptions and details, and other documentation obtained from (or pertinent to) these tests shall be identified, dated, signed by the analyst performing the test, and submitted. For candidate methods for PM<INF>2.5, all submitted information must meet the requirements of the ANSI/ASQC E4, sections 3.3.1, paragraphs 1 and 2 (Reference 1) of Appendix A of this Subpart. Sec. 53.31 Test conditions. (a) All methods. All test measurements made or test samples collected by means of a sample manifold as specified in Sec. 53.30(d)(2) shall be at a room temperature between 20 deg. and 30 deg.C, and at a line voltage between 105 and 125 volts. All methods shall be calibrated as specified in paragraph (c) of this section prior to initiation of the tests.
(b) Samplers and automated methods. (1) Setup and start-up of the test analyzer, test sampler(s), and reference method (if applicable) shall be in strict accordance with the applicable operation manual(s). If the test analyzer does not have an integral strip chart or digital data recorder, connect the analyzer output to a suitable strip chart or digital data recorder. This recorder shall have a chart width of at least 25 centimeters, a response time of 1 second or less, a deadband of not more than 0.25 percent of full scale, and capability of either reading measurements at least 5 percent below zero or offsetting the zero by at least 5 percent. Digital data shall be recorded at appropriate time intervals such that trend plots similar to a strip chart recording may be constructed with a similar or suitable level of detail.
(2) Other data acquisition components may be used along with the chart recorder during the conduct of these tests. Use of the chart recorder is intended only to facilitate visual evaluation of data submitted.
(3) Allow adequate warmup or stabilization time as indicated in the applicable operation manual(s) before beginning the tests. (c) Calibration. The reference method shall be calibrated according to the appropriate appendix to part 50 of this chapter (if it is a manual method) or according to the applicable operation manual(s) (if it is an automated method). A candidate manual method (or portion thereof) shall be calibrated, according to the applicable operation manual(s), if such calibration is a part of the method. (d) Range. Except as provided in paragraph (d)(2) of this section, each method shall be operated in the range specified for the reference method in the appropriate appendix to part 50 of this chapter (for manual reference methods), or specified in Table B-1 of subpart B of this part (for automated reference methods). (e) Operation of automated methods. (1) Once the test analyzer has been set up and calibrated and tests started, manual adjustment or normal periodic maintenance is permitted only every 3 days. Automatic adjustments which the test analyzer performs by itself are permitted at any time. At 3-day intervals only adjustments and periodic maintenance as specified in the manual referred to in Sec. 53.4(b)(3) are permitted. The submitted records shall show clearly when manual adjustments were made and describe the operations performed. (2) All test measurements shall be made with the same test analyzer; use of multiple test analyzers is not permitted. The test analyzer shall be operated continuously during the entire series of test measurements.
(3) If a test analyzer should malfunction during any of these tests, the entire set of measurements shall be repeated, and a detailed explanation of the malfunction, remedial action taken, and whether recalibration was necessary (along with all pertinent records and charts) shall be submitted. Sec. 53.32 Test procedures for methods for SO<INF>2, CO, O<INF>3, and NO<INF>2. (a) Conduct the first set of simultaneous measurements with the candidate and reference methods:
(1) Table C-1 of this subpart specifies the type (1- or 24-hour) and number of [[Page 65806]] measurements to be made in each of the three test concentration ranges. (2) The pollutant concentration must fall within the specified range as measured by the reference method. (3) The measurements shall be made in the sequence specified in Table C-2 of this subpart, except for the 1-hour SO<INF>2 measurements, which are all in the high range.
(b) For each pair of measurements, determine the difference (discrepancy) between the candidate method measurement and reference method measurement. A discrepancy which exceeds the discrepancy specified in Table C-1 of this subpart constitutes a failure. (See Figure C-1 of this subpart for a suggested format for reporting the test results.)
(c) The results of the first set of measurements shall be interpreted as follows:
(1) Zero (0) failures. The candidate method passes the test for comparability.
(2) Three (3) or more failures. The candidate method fails the test for comparability.
(3) One (1) or two (2) failures. Conduct a second set of simultaneous measurements as specified in Table C-1 of this subpart. The results of the combined total of first-set and second-set measurements shall be interpreted as follows: (i) One (1) or two (2) failures. The candidate method passes the test for comparability.
(ii) Three (3) or more failures. The candidate method fails the test for comparability.
(4) For sulfur dioxide, the 1-hour and 24-hour measurements shall be interpreted separately, and the candidate method must pass the tests for both 1- and 24-hour measurements to pass the test for comparability.
(d) A 1-hour measurement consists of the integral of the instantaneous concentration over a 60-minute continuous period divided by the time period. Integration of the instantaneous concentration may be performed by any appropriate means such as chemical, electronic, mechanical, visual judgment, or by calculating the mean of not less than 12 equally spaced instantaneous readings. Appropriate allowances or corrections shall be made in cases where significant errors could occur due to characteristic lag time or rise/fall time differences between the candidate and reference methods. Details of the means of integration and any corrections shall be submitted. (e) A 24-hour measurement consists of the integral of the instantaneous concentration over a 24-hour continuous period divided by the time period. This integration may be performed by any appropriate means such as chemical, electronic, mechanical, or by calculating the mean of twenty-four (24) sequential 1-hour measurements. (f) For oxidant and carbon monoxide, no more than six (6) 1-hour measurements shall be made per day. For sulfur dioxide, no more than four (4) 1-hour measurements or one (1) 24-hour measurement shall be made per day. One-hour measurements may be made concurrently with 24- hour measurements if appropriate.
(g) For applicable methods, control or calibration checks may be performed once per day without adjusting the test analyzer or method. These checks may be used as a basis for a linear interpolation-type correction to be applied to the measurements to correct for drift. If such a correction is used, it shall be applied to all measurements made with the method, and the correction procedure shall become a part of the method. Sec. 53.33 Test procedure for methods for lead. (a) Sample collection. Collect simultaneous 24-hour samples (filters) of lead at the test site or sites with both the reference and candidate methods until at least 10 filter pairs have been obtained. If the conditions of Sec. 53.30(d)(4) apply, collect at least 10 common samples (filters) in accordance with Sec. 53.30(d)(4) and divide each to form the filter pairs.
(b) Audit samples. Three audit samples must be obtained from the Quality Assurance Branch (MD-77B), Air Measurements Research Division, National Exposure Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711. The audit samples are \3/4\ x 8-inch glass fiber strips containing known amounts of lead at the following nominal levels: 100 <greek-m>g/strip; 300 <greek-m>g/strip; 750 <greek-m>g/strip. The true amount of lead in total <greek-m>g/strip will be provided with each audit sample. (c) Filter analysis.
(1) For both the reference method and the audit samples, analyze each filter extract 3 times in accordance with the reference method analytical procedure. The analysis of replicates should not be performed sequentially (i.e., a single sample should not be analyzed three times in sequence). Calculate the indicated lead concentrations for the reference method samples in <greek-m>g/m3 for each analysis of each filter. Calculate the indicated total lead amount for the audit samples in <greek-m>g/strip for each analysis of each strip. Label these test results as R<INF>1A, R<INF>1B, R<INF>1C, R<INF>2A, R<INF>2B, * * *, Q<INF>1A, Q<INF>1B, Q<INF>1C, * * *., where R denotes results from the reference method samples; Q denotes results from the audit samples; 1, 2, 3 indicates filter number and A, B, C indicates the first, second, and third analysis of each filter, respectively. (2) For the candidate method samples, analyze each sample filter or filter extract three times and calculate, in accordance with the candidate method, the indicated lead concentration in <greek-m>g/ m3 for each analysis of each filter. Label these test results as C<INF>1A, C<INF>1B, C<INF>2C, * * *, where C denotes results from the candidate method. (For candidate methods which provide a direct measurement of lead concentrates without a separable procedure, C<INF>1A=C<INF>1B=C<INF>1C, C<INF>2A=C<INF>2B=C<INF>2C, etc.) [GRAPHIC] [TIFF OMITTED] TP13DE96.051 (d) For the reference method, calculate the average lead concentration for each filter by averaging the concentrations calculated from the three analyses: where I is the filter number. (e) Disregard all filter pairs for which the lead concentration as determined in the previous paragraph (d) of this section by the average of the three reference method determinations, falls outside the range of 0.5 to 4.0 <greek-m>g/m3. All remaining filter pairs must be subjected to both of the following tests for precision and comparability. At least five filter pairs must be within the 0.5 to 4.0 <greek-m>g/m3 range for the tests to be valid. (f) Test for precision. (1) Calculate the precision (P) of the analysis (in percent) for each filter and for each method, as the maximum minus the minimum divided by the average of the three concentration values, as follows: [GRAPHIC] [TIFF OMITTED] TP13DE96.052 or
[GRAPHIC] [TIFF OMITTED] TP13DE96.053 where I indicates the filter number.
(2) If any reference method precision value (P<INF>Ri) exceeds 15 percent, the precision of the reference method analytical procedure is out of control. Corrective action must be taken to determine the source(s) of imprecision and the reference method determinations must be repeated [[Page 65807]] according to paragraph (c) of this section, or the entire test procedure (starting with paragraph (a) of this section) must be repeated.
(3) If any candidate method precision value (P<INF>Ci) exceeds 15 percent, the candidate method fails the precision test. (4) The candidate method passes this test if all precision values (i.e., all P<INF>Ri's and all P<INF>Ci's) are less than 15 percent. (g) Test for accuracy.
(1) (i) For the audit samples calculate the average lead concentration for each strip by averaging the concentrations calculated from the three analyses: [GRAPHIC] [TIFF OMITTED] TP13DE96.054 where i is audit sample number.
(ii) Calculate the percent difference (D<INF>q) between the indicated lead concentration for each audit sample and the true lead concentration (T<INF>q) as follows: [GRAPHIC] [TIFF OMITTED] TP13DE96.055 (2) If any difference value (D<INF>qi) exceeds <plus-minus>5 percent the accuracy of the reference method analytical procedure is out of control. Corrective action must be taken to determine the source of the error(s) (e.g., calibration standard discrepancies, extraction problems, etc.) and the reference method and audit sample determinations must be repeated according to paragraph (c) of this section or the entire test procedure (starting with paragraph (a) of this section) must be repeated.
(h) Test for comparability.
(1) For each filter pair, calculate all nine possible percent differences (D) between the reference and candidate methods, using all nine possible combinations of the three determinations (A, B, and C) for each method, as: [GRAPHIC] [TIFF OMITTED] TP13DE96.056 where i is the filter number, and n numbers from 1 to 9 for the nine possible difference combinations for the three determinations for each method (j= A, B, C, candidate; k= A, B, C, reference). (2) If none of the percent differences (D) exceed <plus-minus>20 percent, the candidate method passes the test for comparability. (3) If one or more of the percent differences (D) exceed <plus-minus>20 percent, the candidate method fails the test for comparability.
(i) The candidate method must pass both the precision test and the comparability test to qualify for designation as an equivalent method. Sec. 53.34 Test procedure for methods for PM<INF>10 and PM<INF>2.5. (a) Collocated measurements. Set up three reference method samplers collocated with three candidate method samplers or analyzers at each of the number of test sites specified in Table C-4 of this subpart. At each site, obtain as many sets of simultaneous PM<INF>10 or PM<INF>2.5 measurements as necessary (see 53.34(c)(3)), each set consisting of three reference method and three candidate method measurements, all obtained simultaneously. For PM<INF>2.5 Class II candidate methods, at least two collocated PM<INF>10 reference method samplers are also required to obtain PM<INF>2.5/PM<INF>10 ratios for each sample set. Candidate PM<INF>10 method measurements shall be 24-hour integrated measurements; PM<INF>2.5 measurements may be either 24- or 48-hour integrated measurements. All collocated measurements in a sample set must cover the same 24- or 48-hour time period. For samplers, retrieve the samples promptly after sample collection and analyze each sample according to the reference method or candidate method, as appropriate, and determine the PM<INF>10 or PM<INF>2.5 concentration in <greek-m>g/ m3. If the conditions of Sec. 53.30(d)(4) apply, collect sample sets only with the three reference method samplers. Guidance for quality assurance procedures for PM<INF>2.5 methods is found in section 2.12 of the Quality Assurance Handbook. (b) Sequential samplers. For sequential samplers, the sampler shall be configured for the maximum number of sequential samples and shall be set for automatic collection of all samples sequentially such that the test samples are collected equally, to the extent possible, among all available sequential channels or utilizing the full available sequential capability. At least 2 valid samples, one each above and below the applicable concentration limit specified in paragraph (c)(3) of this section, shall be obtained from each sequential channel in the maximum-channel configuration of the sampler. (c) Test for comparability. (1) For each of the measurement sets, calculate the average PM<INF>10 or PM<INF>2.5 concentration obtained with the reference method samplers: [GRAPHIC] [TIFF OMITTED] TP13DE96.057 where R denotes results from the reference method, I is the sampler number, and j is the set.
(2)(i) For each of the measurement sets, calculate the precision of the reference method PM<INF>10 or PM<INF>2.5 measurements as: [GRAPHIC] [TIFF OMITTED] TP13DE96.058 if R<INF>j is below: 80 <greek-m>g/m3 for PM<INF>10 methods; 40 <greek-m>g/m3 for 24-hour PM<INF>2.5 at single test sites for Class I candidate methods;
40 <greek-m>g/m3 for 24-hour PM<INF>2.5 at sites having PM<INF>2.5/PM<INF>10 ratios >0.75; 30 <greek-m>g/m3 for 48-hour PM<INF>2.5 at single test sites for Class I candidate methods;
30 <greek-m>g/m3 for 48-hour PM<INF>2.5 at sites having PM<INF>2.5/PM<INF>10 ratios >0.75; 30 <greek-m>g/m3 for 24-hour PM<INF>2.5 at sites having PM<INF>2.5/PM<INF>10 ratios <0.40; and 20 <greek-m>g/m3 for 48-hour PM<INF>2.5 at sites having PM<INF>2.5/PM<INF>10 ratios >0.75. (ii) Otherwise, calculate the precision of the reference method PM<INF>10 or PM<INF>2.5 measurements as: [[Page 65808]] [GRAPHIC] [TIFF OMITTED] TP13DE96.059 (3) If R<INF>j falls outside the acceptable concentration range specified in Table C-4 of this subpart for any set, or if P<INF>j or RP<INF>j, as applicable, exceeds the value specified in Table C-4 of this subpart for any set, that set of measurements shall be discarded. For each site, Table C-4 of this subpart specifies the minimum number of sample sets required for various conditions, and Sec. 53.30(b)(5) specifies the PM<INF>2.5/PM<INF>10 ratio requirements applicable to Class II candidate equivalent methods. Additional measurement sets shall be collected and analyzed, as necessary, to provide a minimum of 10 acceptable measurement sets for each test site. If more than 10 measurement sets are collected that meet the above criteria, all such measurement sets shall be used to demonstrate comparability. (4) For each of the acceptable measurement sets, calculate the average PM<INF>10 or PM<INF>2.5 concentration obtained with the candidate method samplers:
[GRAPHIC] [TIFF OMITTED] TP13DE96.060 where C denotes results from the candidate method, I is the sampler number, and j is the set.
(5) For each site, plot the average PM<INF>10 or PM<INF>2.5 measurements obtained with the candidate method (C<INF>j) against the corresponding average PM<INF>10 or PM<INF>2.5 measurements obtained with the reference method (R<INF>j). For each site, calculate and record the linear regression slope and intercept, and the correlation coefficient.
(6) If the linear regression parameters calculated above meet the values specified in Table C-4 of this subpart for all test sites, the candidate method passes the test for comparability. Tables to Subpart C of Part 53
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
Table C-1.--Test Concentration Ranges, Number of Measurements Required, and Maximum Discrepancy Specification 
```
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 Simultaneous measurements required Maximum
 ---------------------------------------------------- discrepancy 
Pollutant Concentration range parts per million 1-hr 24-hr specification, 
 -------------------------------------------------- parts per 
 First set Second set First set Second set million 
```
Oxidants.................... Low 0.06 to 0.10................ 5 6 ........... ........... 0.02
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 Med 0.15 to 0.25................ 5 6 ........... ........... .03
 High 0.35 to 0.45............... 4 6 ........... ........... .04
 ------------------------------------------------------
 Total............................ 14 18 ........... ........... ................
 ======================================================
```
Carbon monoxide........... Low 7 to 11........................ 5 6 ........... ........... 1.5
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 Med 20 to 30....................... 5 6 ........... ........... 2.0
 High 35 to 45...................... 4 6 ........... ........... 3.0
 ------------------------------------------------------
 Total.............................. 14 18 ........... ........... ................
 ======================================================
```
Sulfur dioxide............ Low 0.02 to 0.05............... ........... ........... 3 3 0.02
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 Med 0.10 to 0.15................ ........... ........... 2 3 .03
 High 0.30 to 0.50............... 7 8 2 2 .04
 ------------------------------------------------------
 Total.................................. 7 8 7 8 ................
 =======================================================
```
Nitrogen dioxide.......... Low 0.02 to 0.08................ ........... ........... 3 3 0.02
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 Med 0.10 to 0.20................ ........... ........... 2 3 .03
 High 0.25 to 0.35............... ........... ........... 2 2 .03
 -----------------------------------------------------
 Total......................... ........... ........... 7 8 ................
```
[[Page 65809]] Table C-2.--Sequence of Test Measurements

Note: EPA no longer updates this information, but it may be useful as a reference or resource.
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 Concentration range
```
Measurement ----------------------------------------
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 First set Second set 
```
1.............................. Low............... Medum. 2.............................. High.............. High. 3.............................. Medium............ Low. 4.............................. High.............. High. 5.............................. Low............... Medium. 6.............................. Medium............ Low. 7.............................. Low............... Medium. 8.............................. Medium............ Low. 9.............................. High.............. High. 10............................. Medium............ Low. 11............................. High.............. Medium. 12............................. Low............... High. 13............................. Medium............ Medium. 14............................. Low............... High. 15............................. .................. Low. 16............................. .................. Medium. 17............................. .................. Low. 18............................. .................. High.
Table C-3.--Test Specifications for Lead Methods

Note: EPA no longer updates this information, but it may be useful as a reference or resource.
Concentration range, <greek-m>g/m\3\.......................... 0.5-4.0 Minimum number of 24-hr measurements.......................... 5 Maximum analytical precision, percent......................... 5 Maximum analytical accuracy, percent.......................... <plus-mi
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 n5
```
Maximum difference, percent of reference method............... <plus-mi
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 n20
```
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 Table C-4.--Test Specifications for PM<INF>10 and PM<INF>2.5 Methods
```
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 PM<INF>2.5
 Specification PM<INF>10 -----------------------------------------------------
 Class I Class II
```
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
Acceptable concentration range 30-300................... 10-200................... 10-200
 (R<INF>j), <greek-m>g/m3.
Minimum number of test sites... 2........................ 1........................ 2 
Number of candidate method 3........................ 3........................ 3 
 samplers per site.
Number of reference method 3........................ 3........................ 3 
 samplers per site.
Minimum number of acceptable
 sample sets per site for PM<INF>10:
```
R<INF>j < 80 <greek-m>g/m3...... 3........................ ......................... ......................... R<INF>j > 80 <greek-m>g/m3...... 3........................ ......................... ......................... Total.................. 10....................... ......................... .........................
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
Minimum number of acceptable
 sample sets per site for
 PM<INF>2.5:
 Single test site for Class
 I candidate equivalent
 methods:
```
R<INF>j < 40 <greek-m>g/m3 ....................... 3a....................... .........................
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 for 24-hr or R<INF>j < 30
 <greek-m>g/m3 for 48-
 hr samples.
```
R<INF>j > 40 <greek-m>g/m3 ....................... 3a....................... .........................
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 for 24-hr or R<INF>j > 30
 <greek-m>g/m3 for 48-
 hr samples.
 Sites at which the PM<INF>2.5/
 PM<INF>10 ratio must be > 0.75:
 R<INF>j < 40 <greek-m>g/m3 ....................... ......................... 3a
 for 24-hr or R<INF>j < 30
 <greek-m>g/m3 for 48-
 hr samples.
 R<INF>j > 40 <greek-m>g/m3 ....................... ......................... 3a
 for 24-hr or R<INF>j > 30
 <greek-m>g/m3 for 48-
 hr samples.
 Sites at which the PM<INF>2.5/
 PM<INF>10 ratio must be < 0.40:
 R<INF>j < 30 <greek-m>g/m3 ....................... ......................... 3a
 for 24-hr or R<INF>j < 20
 <greek-m>g/m3 for 48-
 hr samples.
 R<INF>j > 30 <greek-m>g/m3 ....................... ......................... 3a
 for 24-hr or R<INF>j > 20
 <greek-m>g/m3 for 48-
 hr samples.
Total, each site............... ....................... 10a...................... 10a
```
Precision of replicate 5 <greek-m>g/m3 or 7%.... 2 <greek-m>g/m3 or 5%.... 2 <greek-m>g/m3 or 5%
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 reference method measurements,
 P<INF>j or RP<INF>j.
```
Slope of regression 1<plus-minus>0.1......... 1<plus-minus>0.05........ 1<plus-minus>0.05
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 relationship.
```
Intercept of regression 0<plus-minus>5........... 0<plus-minus>1........... 0<plus-minus>1
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 relationship, <greek-m>g/m3.
```
Correlation of reference method <gr-thn-eq>0.97.......... <gr-thn-eq>0.97.......... <gr-thn-eq>0.97
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 and candidate method
 measurements.
```
a For sequential samplers, at least 2 samples, one above and one below the applicable concentration limit shall be obtained from each sequential channel in the maximum sequential configuration of the sampler. Therefore, the number of samples in each category, and possibly the total number of samples, will be dependent on the
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 number of sequential channels available.
```
BILLING CODE 6560-50-P [[Page 65810]] FIGURES TO SUBPART C OF PART 53 Figure C-1.--Suggested Format for Reporting Test Results [GRAPHIC] [TIFF OMITTED] TP13DE96.061 [[Page 65811]] BILLING CODE 6560-50-C Appendix A to Subpart C of Part 53--References
1. American National Standard--Specifications and Guidelines for Quality Systems for Environmental Data Collection and Environmental Technology Programs, ANSI/ASQC E4-1994. Available from American Society for Quality Control, 611 East Wisconsin Avenue, Milwaukee, WI 53202.
2. Subpart E is added to read as follows: Subpart E--Procedures for Testing Physical (Design) and Performance Characteristics of Reference Methods and Class I Equivalent Methods for PM.<INF>2.5
 Sec.
 53.50 General provisions.
 53.51 Requirements to show compliance with design specifications. 53.52 Comprehensive procedure to test sampler performance under various environmental conditions (environmental chamber tests). 53.53 Post-sampling filter temperature control test. 53.54 Leak check test.
 53.55 Flow rate cut-off test.
 53.56 Operational field precision test. 53.57 Aerosol transport test for Class I sequential samplers. Tables to Subpart E of Part 53 Table E-1--Test conditions for Sec. 53.52 comprehensive 24-hour tests
 Table E-2--Summary of test requirements for reference and Class I equivalent methods for PM.<INF>2.5 Figures to Subpart E of Part 53 Figure E-1--Designation Check List
 Figure E-2--Product Manufacturing Check List Figure E-3--Suggested test configuration for simulating reduced barometric pressure for comprehensive test procedure (Sec. 53.52) Appendix to Subpart E of Part 53--References Subpart E--Procedures for Testing Physical (Design) and Performance Characteristics of Reference Methods and Class I Equivalent Methods for PM.<INF>2.5 Sec. 53.50 General provisions. (a) This subpart sets forth the specific tests that must be carried out and the test results, evidence, documentation, and other materials that must be provided to EPA to demonstrate that a PM<INF>2.5 sampler associated with a candidate reference method or Class I equivalent method meets all design and performance specifications set forth in Appendix L of part 50 of this chapter as well as additional requirements specified in this subpart E. Some of these tests may also be applicable to portions of a Class II or III equivalent method sampler, as determined under subpart F of this part. (b) Samplers associated with candidate reference methods for PM<INF>2.5 shall be subject to the provisions, specifications, and test procedures prescribed in Secs. 53.51 through 53.56. Samplers associated with candidate Class I equivalent method for PM<INF>2.5 shall be subject to the provisions, specifications, and test procedures prescribed in all sections of this Subpart. Samplers associated with candidate Class II or Class III equivalent method for PM<INF>2.5 shall be subject to the provisions, specifications, and test procedures prescribed in all applicable sections of this Subpart, as specified in subpart F of this part.
 (c) Section 53.51 pertains to test results and documentation required to demonstrate compliance of a candidate method sampler with the design specifications set forth in Appendix L of part 50 of this chapter. Test procedures prescribed in Secs. 53.52 through 53.56 pertain to performance tests required to demonstrate compliance of a candidate method sampler with the performance specifications set forth in Appendix L of part 50 of this chapter, as well as additional requirements specified in this subpart E. These latter test procedures shall be used to test the performance of candidate samplers against the performance specifications and requirements specified in each procedure and summarized in Table E-1 of this subpart. [[Page 65812]] (d) Test procedures prescribed in Sec. 53.57 do not apply to candidate reference method samplers. These procedures apply primarily to candidate class I equivalent method samplers for PM<INF>2.5 that have a sample air flow path configuration upstream of the sample filter that is modified from that specified for the reference method sampler-- as set forth in Drawings L-18 and L-24 of Appendix L to part 50 of this chapter to provide for sequential sample capability. The additional tests determine the adequacy of aerosol transport through any altered components or supplemental devices that are used in a candidate sampler upstream of the filter to achieve the sequential sample capability. These tests may also apply, with appropriate adaptation, if necessary, to candidate samplers having minor deviations from the specified reference method sampler for purposes other than sequential operation. In addition to the other test procedures in this subpart, these test procedures shall be used to further test the performance of such equivalent method samplers against the performance specifications given in Table E-2 of this subpart.
 (e) Tests of a candidate sampler for sample flow rate capacity and regulation, flow rate control, flow rate measurement accuracy, ambient temperature and pressure measurement accuracy, filter temperature control during sampling, and correct determination of elapsed sample time, average volumetric flow rate, and flow rate variation are all combined into a comprehensive test procedure (Sec. 53.52) that is carried out over four 24-hour test periods under multiple test conditions. Other performance parameters are tested individually with specific test procedures (Secs. 53.53--53.57). (f) A 10-day field test of measurement precision is required for both reference and equivalent method samplers. This test requires collocated operation of 3 candidate method samplers at a field test site. For candidate equivalent method samplers, this test may be combined and carried out concurrently with the test for comparability to the reference method specified under Sec. 53.34, which requires collocated operation of three reference method samplers and three candidate equivalent method samplers.
 (g) All tests and collection of test data shall be in accordance with the requirements of Reference 1, section 4.10.5 (ISO 9001) and Reference 2, Part B, section 3.3.1, paragraphs 1 and 2 and Part C, section 4.6 (ANSI/ASQC E4) in appendix A of this subpart. All test data and other documentation obtained specifically from or pertinent to these tests shall be identified, dated, signed by the analyst performing the test, and submitted to EPA in accordance with subpart A of this part. Sec. 53.51 Requirements to show compliance with design specifications. For the purposes of this document the definitions of ISO registered facility and ISO-certified auditor are found in Sec. 53.1(t) and (u). An exception to this reliance by EPA on ISO affiliate audits is the requirement of the submission of the operation or instruction manual associated with the candidate method to EPA prior to designation. This manual is required under Sec. 53.4(b)(3). The EPA has determined that acceptable technical judgment for review of this manual may not be assured by ISO affiliates, and approval of this manual will therefore be accomplished by the EPA.
 (a) Overview. (1) In the absence of performance standards for some features of the FRM sampler system, and of the EPA resources to directly review and ensure manufacturer performance in producing samplers according to the EPA design specifications in 40 CFR part 50, Appendix L, EPA considers it necessary to require manufacturers to meet two kinds of requirements to ensure their compliance with the design specifications of 40 CFR part 50, Appendix L. (2) The subsequent paragraphs of this section specify certain documentation that must be submitted and tests that are required to demonstrate that instruments associated with a designated reference or equivalent method for PM<INF>2.5 are properly manufactured to meet all applicable design specifications and have been properly tested according to all applicable test requirements for such designation. Documentation is required to show that instruments and components are manufactured or assembled in an ISO-9001-registered (or equivalent) facility under a quality system that meets ISO-9001 [[Page 65813]] requirements for manufacturing quality control and testing. (3) In addition, specific tests are required to verify that two critical features of reference method samplers.impactor jet diameter and the surface finish of surfaces specified to be anodized.meet the specifications of 40 CFR part 50, Appendix L. A checklist is required to provide certification by an ISO-certified auditor that all performance and other required tests have been properly and appropriately conducted. Following designation of the method, another checklist is required, initially and annually, to provide an ISOqualified (or equivalent) auditor's certification that an adequate and appropriate quality system is being implemented in the instrument manufacturing process.
 (b) ISO Registration of manufacturing facility. (1) The applicant must submit documentation verifying that the samplers associated with the candidate method will be manufactured in an ISO 9001-registered facility (as defined in Sec. 53.1(u)) and that the manufacturing facility is maintained in compliance with all applicable ISO 9001 requirements (Reference 1 in appendix A of this subpart). The documentation shall indicate the date of the original ISO 9001 registration for the facility and shall include a copy of the most recent certification of continued ISO 9001 facility registration. If the manufacturer does not wish to initiate or complete ISO 9001 registration for the manufacturing facility, documentation must be included in the application to EPA describing an alternative method to demonstrate that the facility meets the same general requirements as required for ISO registration. In this case, the applicant must provide documentation in the application to demonstrate, by required ISOcertified auditor's inspections, that a quality system is in place which is adequate to document and monitor that the sampler system components all conform to the design, performance and other requirements specified in Appendix L of part 50 of this chapter. (2) Phase-in period. For a period of 1 year following the effective date of this subpart, a candidate reference or equivalent method for PM<INF>2.5 that utilizes a sampler manufactured in a facility that is not ISO 9001-registered or otherwise approved by the EPA under paragraph (b)(1) of this section may be conditionally designated as a reference or equivalent method under this part. Such conditional designation will be considered on the basis of evidence submitted in association with the candidate method application showing that appropriate efforts are currently underway to seek ISO 9001 registration or alternative approval of the facility's quality system under paragraph (b)(1) of this section within the next 12 months. Such conditional designation shall expire 1 year after the date of the Federal Register notice of the conditional designation unless documentation verifying successful ISO 9001 registration for the facility or other EPA-acceptable quality system review and approval process of the production that will manufacture the samplers is submitted at least 30 days prior to the expiration date. (c) Sampler Manufacturing Quality Control. The manufacturer must ensure that all components used in the manufacture of PM<INF>2.5 samplers to be sold as reference or equivalent methods and that are specified by design in Appendix L of part 50 of this chapter are fabricated or manufactured exactly as specified. If the manufacturer's QC records show that its QC and QA system of standard process control inspections (of a set number and frequency of testing that is less than 100%) complies with the applicable QA provisions of section 4 of Reference 4 in Appendix A of this subpart and prevents nonconformances, 100% testing shall not be required until that conclusion is disproved by customer return or other independent manufacturer or customer test records. If problems are uncovered, inspection to verify conformance to the drawings, specifications, and tolerances shall be performed. See also paragraph (e) of this section (final assembly and inspection requirements).
 (d) Specific tests and supporting documentation required to verify conformance to critical component specifications. (1) Verification of PM<INF>2.5 impactor jet diameter. The diameter of the jet of each impactor manufactured for a PM<INF>2.5 sampler under the impactor design specifications set forth in Appendix L of part 50 of this chapter shall be verified against the tolerance specified on the drawing, using standard, NIST-traceable plug gages. This test shall be a final check of the jet diameter following all fabrication operations, and a record shall be kept of this final check. Submit evidence that this procedure is incorporated in the ISO 9001-certified manufacturing procedure, that the test is or will be routinely implemented, and that an appropriate procedure is in place for the disposition of units that fail this tolerance test.
 (2) Verification of surface finish. The anodization process used to treat surfaces specified to be anodized shall be verified by testing treated specimen surfaces for weight and corrosion resistance to ensure that the coating obtained conforms to the coating specification. The specimen surfaces shall be finished in accordance with military standard specification 8625F, Type II, Class I (Reference 4) in the same way the sampler surfaces are finished, and tested, prior to sealing, as specified in Section 4.5.2 of Reference 4 in Appendix A of this subpart.
 (e) Final assembly and inspection requirements. Each sampler shall be tested after manufacture and before delivery to the final user. Each manufacturer shall document its post-manufacturing test procedures. As a minimum, each test shall consist of the following: Tests of the overall integrity of the sampler, including leak tests; calibration or verification of the calibration of the flow measurement device, barometric pressure sensors, and temperature sensors; and operation of the sampler with a filter in place over a period of at least 48 hours. The results of each test shall be suitably documented and shall be subject to review by an ISO 9001 auditor. (f) Manufacturer's audit checklists. Manufacturers shall require ISO 9001 auditors to sign and date a statement indicating that the auditor is aware of the appropriate manufacturing specifications contained in Appendix L of part 50 of this chapter and the test or verification requirements in this subpart. Manufacturers shall also require ISO 9001 auditors to complete the checklists, shown in Figures E-1 and E-2 of this subpart, which describe the manufacturer's ability to meet the requirements of the standard for both designation testing and product [[Page 65814]] manufacture. Refer to Reference 5 for additional guidance on the scope and detail required for the checklist evaluations. (1) Designation testing checklist. The completed statement and checklist as shown in Figure E-1 of this subpart shall be submitted with the application for reference or equivalent method determination. (2) Product manufacturing checklist. Manufacturers shall require ISO 9001 auditors to complete the attached Production Checklist, which evaluates the manufacturer on its ability to meet the requirements of the standard in maintaining quality control in the production of reference or equivalent devices. The completed statement and checklist shall be submitted with the application for reference or equivalent method determination. As set forth in subpart A of this part, this checklist must be completed and submitted annually to retain a reference or equivalent method designation for a PM<INF>2.5 method. (3) If the conditions of paragraph (b)(2) of this section apply, a candidate reference or equivalent method for PM<INF>2.5 may be conditionally designated as a reference or equivalent method under this part 53 without the submission of the checklists described in paragraphs (f) (1) and (2) of this section. Such conditional designation shall expire 1 year after the date of the Federal Register notice of the conditional designation unless the checklists are submitted at least 30 days prior to the expiration date. Sec. 53.52 Comprehensive procedure to test sampler performance under various environmental conditions (environmental chamber tests). (a) Overview. This test procedure is a combined procedure to test the following performance parameters:
 (1) Sample flow rate, flow rate regulation, and flow rate measurement accuracy;
 (2) Ambient air temperature and barometric pressure measurement accuracy;
 (3) Filter temperature control during sampling; and (4) Elapsed sampling time accuracy. The performance parameters tested under this procedure, the corresponding minimum performance specifications, and the applicable test conditions are summarized in Table E-2 of this subpart. Each performance parameter tested, as described or determined in the test procedure, must meet or exceed the performance specification given in Table E-2 of this subpart. The candidate sampler must meet all specifications for the associated PM<INF>2.5 method to be considered for designation as a reference or equivalent method. (b) Technical definition. Sample flow rate means the quantitative volumetric flow rate of the air stream caused by the sampler to enter the sampler inlet and pass through the sample filter, measured in actual volume units at the temperature and pressure of the air as it enters the inlet.
 (c) Required test equipment.
 (1) Environmental chamber or other temperature-controlled environment or environments, capable of obtaining and maintaining the various temperatures between -20 deg.C to +40 deg.C as required for the test with an accuracy of <plus-minus>2 deg.C. The test environment(s) must be capable of maintaining temperature within the specified limits continuously with the additional heat load of the operating test sampler in the environment. [Henceforth, where the test procedures specify a test or environmental ``chamber,'' an alternative temperature-controlled environmental area or areas may be substituted, provided the required test temperatures and all other test requirements are met. See paragraph (f)(1) of this section] (2) Variable voltage ac power transformer, range 100 to 130 Vac, with sufficient VA capacity to operate the test sampler continuously under the test conditions.
 (3) Flow rate meter, suitable for measuring the actual volumetric sampler flow rate at the sampler downtube in either an open system or in a closed system operating below atmospheric pressure, range 10 to 25 actual L/min, 2 percent certified accuracy, NIST-traceable, over a temperature range of -30 deg.C to +50 deg.C and pressure range of 600 to 800 mm Hg, with continuous (analog) recording capability or digital recording at intervals of not more than 5 minutes. Mass flow meter type recommended; however, note that temperature and pressure corrections are generally required to convert measured mass flow rate to actual volumetric flow rate.
 (4) Ambient air temperature recorder, range -30 deg.C to +50 deg.C, certified accurate to within 0.5 deg.C with a radiation error of 0.2 deg.C or less under a solar radiation intensity of 1000 watts/m2, as described in Reference 6 in appendix A of this subpart. (5) Barometric pressure meter, range 600 to 800 mm Hg, certified accurate to 2 mm Hg.
 (6) Miniature temperature sensor, capable of being installed in the sampler without introducing air leakage and capable of measuring the sample air temperature within 1 cm of the center of the filter, downstream of the filter, certified accurate to within 0.5 deg.C, NIST traceable, with continuous (analog) recording capability or digital recording at intervals of not more than 5 minutes. (7) Means for creating or simulating the effect of a reduced barometric pressure on the test sampler during sampler operation, capable of simulating barometric pressures ranging from 730 to 600 mm Hg. A suggested, closed-system technique for a hypothetical sampler is illustrated in Figure E-3 of this subpart, but the configuration shown may have to be modified or adapted to accommodate the specific design of the actual candidate method sampler. The sampler-specific technique or apparatus proposed by the applicant for simulating barometric pressure for purposes of this test may be submitted for pre-approval of concept prior to conducting the test. Alternatively, a hypobarometric chamber or other test environment with capability of maintaining barometric pressures ranging from local actual barometric pressure to 600 mm Hg, as well as the temperature capability specified in paragraph (c)(1) of this section, shall be used.
 (8) Means, such as a solar-spectrum lamp or lamps, for generating or simulating thermal radiation in approximate spectral content and intensity equivalent to solar insolation of 1000 watts/m2 (1.43 langleys/min) inside the environmental chamber. (9) AC rms voltmeter, accurate to 0.5 volts. (10) Means for creating an additional pressure drop of 55 mm Hg in the sampler to simulate a heavily loaded filter, such as an orifice or flow restrictive plate installed in the filter holder or a valve or other flow restrictor temporarily installed in the flow path near the filter.
 (11) Time measurement system, accurate to within 10 seconds per day.
 (12) Radiometer, to measure the intensity of the simulated solar radiation in the test environment, range 0--1500/m2. (d) Calibration of test measurement instruments. Submit documentation showing evidence of recent calibration, calibration accuracy, and NIST-traceability (if required) of all measurement instruments used in the tests. The accuracy of flow meters shall be verified at the highest and lowest pressures and temperatures used in the tests and shall be checked at zero and one or more non-zero flow rates within 7 days of test use. Where an instrument's measurements are to be recorded with an analog recording [[Page 65815]] device, the accuracy of the entire instrument-recorder system shall be calibrated or verified.
 (e) Test setup. (1) The test sampler shall be set up for testing in the temperature-controlled chamber. Setup of the sampler shall be performed as described in the sampler's operation or instruction manual referred to in Sec. 53.4(b)(3). The sampler shall be installed upright and set up in its normal configuration for collecting PM<INF>2.5 samples, except that the sample air inlet shall be removed to permit measurement of the sampler flow rate.
 (2) The certified flow rate meter shall be connected to the test sampler so as to accurately measure the sampler flow rate at the entrance to the sampler (i.e., the flow rate that would enter the sampler inlet if the inlet had not been removed). (3) The sampler shall be provided with ac line power from the variable voltage ac power transformer, which shall be initially set to a nominal voltage of 115 volts ac (rms). (4) The miniature temperature sensor shall be installed in the test sampler such that it accurately measures the air temperature 1 cm from the center of the filter on the downstream side of the filter. The sensor shall be installed in a way such that no external or internal leakage is created by the sensor installation. (5) If a closed-system means for simulating reduced barometric pressure in the sampler, as suggested in paragraph (c)(7) of this section, is to be used in lieu of a hypobarometric chamber, the necessary apparatus shall be installed on the test sampler as appropriate, in such a way that the certified flow rate meter will still accurately measure the sampler flow rate. Also, the barometric pressure meter shall be installed to accurately measure the simulated or actual reduced barometric pressure to which the sampler is subjected during the test.
 (6) The solar radiant energy source shall be installed in the test chamber such that the entire test sampler is irradiated in a manner similar to the way it would be irradiated by solar radiation if it were located outdoors in an open area on a sunny day, with the radiation arriving at an angle of between 30 and 45 degrees from vertical and such that the intensity of the radiation received by all sampler surfaces that receive direct radiation is not less than 1000 watts/ cm2, measured in a plane perpendicular to the incident radiation. The incident radiation shall be oriented with respect to the sampler such that the area of the sampler's ambient temperature sensor (or temperature shield) receives direct radiation as it would or could during normal outdoor installation. Also, the sensor must not be shielded from the radiation by a sampler part in a way that would not occur at other normal insolation angles or directions. (7) The ambient air temperature recorder shall be installed in the test chamber such that it will accurately measure the temperature of the air in the chamber without being unduly affected by the chamber's air temperature control system or by the radiant energy from the solar radiation source that may be present inside the test chamber. (f) Procedure. (1) The test sampler shall be tested during operation over four (4) 24-hour sample collection periods (Test numbers 1--4) under the conditions specified in Table E-1 of this subpart. The test chamber temperature shall be held at the specified initial temperature for the first 8 hours of each test period, during which various performance parameters are measured. During hours 9 through 21 of each test period, the chamber temperature is transitioned from the initial to the final specified temperature; the temperature profile is unspecified during this period, provided that the final specified temperature is achieved before the start of hour 22 of each test period. The specified final temperature shall be maintained during hours 22 through 24 of each test period. (2) Prepare the test sampler for normal sample collection operation as directed in the sampler's operation or instructional manual. If the sampler has multiple (sequential) sample capability, this capability may be used for the four 24-hour tests, if desired. Convenient start and stop times for a 24<plus-minus>0.1 hour test period shall be set in the test sampler to effect automatic sampler operation for each test period. Test periods are not required to start at midnight; each test period may start at any time of day.
 (3) Carry out a leak test of the sampler as described in the sampler's operation manual. The leak test must be properly passed before other tests are carried out.
 (4) At the beginning of each test period, the solar insolation source, as described in paragraph (c)(8) of this section, shall be off, and the sampler shall be subject to barometric pressure of not less than 730 mm Hg.
 (5) During each 24-hour test period, continuously record the test chamber air temperature, the filter temperature, and the sampler flow rate, as measured by the test equipment [paragraph (c) of this section], either via a continuous analog recording or digital recording at intervals of not more than 5 minutes. Note and record the actual start and stop times for the sample period. The sampler power line voltage shall be measured and recorded during hours 1 and 24 of the test period and following completion of the specific performance parameter tests during the initial 8-hour portion of the test period. (6) The following tests shall be carried out at some time during hours 1-8 of each 24-hour test period. The time at which the test data for each test are obtained (either time of day or elapsed time since the start of the 24-hour test period, whichever system is used to record flow rate and chamber temperature, to the closest 1 minute) shall be recorded along with the test data. If analog recording is used, the time of each test shall be identified or annotated directly on the strip chart record.
 (i) Determine and record the sampler flow rate, in actual volumetric units, indicated by the sampler, and the corresponding flow rate measured by the flow rate test meter specified in paragraph (c)(3) of this section.
 (ii) Determine and record the ambient (chamber) temperature indicated by the sampler and the corresponding ambient (chamber) temperature measured by the ambient temperature recorder specified in paragraph (c)(4) of this section.
 (iii) Determine and record the ambient (chamber) barometric pressure indicated by the sampler and the corresponding ambient (chamber) barometric pressure measured by the barometric pressure meter specified in paragraph (c)(5) of this section. (iv) Activate the solar radiation source; after at least 2 hours (120 minutes) of sampler operation following the start of simulated insolation exposure, repeat tests in paragraphs (f)(6) (i) and (ii) of this section under continuation of the insolation exposure. (v) Activate the solar radiation source; after at least 2 hours (120 minutes) of sampler operation following the start of simulated solar insolation exposure, subject the sampler to a barometric pressure (actual or simulated) of <ls-thn-eq>600 mm Hg (absolute) while continuing the insolation exposure. After at least 1 hour (60 minutes) of sampler operation at this barometric pressure, repeat tests in paragraphs (f)(6) (i), (ii), and (iii) of this section under continuation of the reduced barometric pressure and insolation exposure.
 (vi) Activate the solar radiation source; after at least 2 hours (120 minutes) of sampler operation following the start of insolation exposure, subject the sampler to a barometric pressure (actual or simulated) of <ls-thn-eq>600 mm Hg [[Page 65816]] while continuing the insolation exposure. After at least 1 hour (60 minutes) of sampler operation at this barometric pressure, provide an additional filter pressure drop of 55 mm Hg, as specified in paragraph (c)(10) of this section and repeat tests in paragraphs (f)(6)(i), and (iii) of this section under continuation of the reduced barometric pressure, increased pressure drop, and insolation exposure. One or more of the power interruptions required in paragraph (f) (6)(vii) of this section may be used, if appropriate, to make necessary adjustments to the sampler to effect the additional filter pressure drop. (vii) Interrupt the ac line electrical power to the sampler for periods of 20 seconds, 40 seconds, 2 minutes, 7 minutes, and 20 minutes, with not less than 5 minutes of electrical power, at the voltage specified for the test, between each power interruption. Record the hour and minute of each power interruption. (7) After completing the special tests under paragraph (f)(6) of this section, the remainder of the 24-hour test period may be completed with the test sampler subjected to any barometric pressure within the range specified in Table
 E-2 of this subpart, with or without the additional filter pressure drop, and with the solar radiation either off or on. (g) Test Results. All requirements in this procedure must be passed in full for each of the four 24-hour tests; no provision is made for additional trials to compensate for failed tests. For each of the four 24-hour test periods, validate the test conditions and determine the test results as follows:
 (1) Chamber temperature control. Examine the continuous record of the chamber temperature obtained in test procedure paragraph (f)(5) of this section and verify that the temperature met the requirements specified in Table E-1 of this subpart at all times during the test. If not, the entire 24-hour test is not valid and must be repeated. (2) Power line voltage. Verify that each of the three power line voltage measurements obtained in test procedure in paragraph (f)(5) of this section met the line voltage requirements specified in Table E-1 of this subpart. If not, the entire 24-hour test is not valid and must be repeated.
 (3) Sample flow rate. (i) From the continuous record of the test sampler flow rate obtained from the flow rate meter in test procedure paragraph (f)(5) of this section, determine the average or instantaneous sampler flow rate, or average flow rate, at intervals of not more than 5 minutes for the entire 24-hour sample period. Calculate the percent difference between the sampler interval flow rate, in actual liters per minute (L/min), and 16.67 L/min, for each interval in test procedures in paragraphs (f)(6)(i), (6)(iv), (6)(v), and (6)(vi) of this section, as follows: [GRAPHIC] [TIFF OMITTED] TP13DE96.062 Where F<INF>i is the measured sampler flow rate for interval I, in actual L/min.
 (ii) All calculated sampler flow rate percent differences must meet the sample flow rate specification listed in Table E-2 of this subpart. (4) Sample flow rate regulation. (i) Using the sampler interval flow rates obtained in paragraph (g)(3) of this section, calculate the average sampler flow rate in actual liters per minute for the 24-hour period, excluding periods of electrical power interruption, as, [GRAPHIC] [TIFF OMITTED] TP13DE96.063 where
 F<INF>ave = average sampler flow rate over the 24-hour test period, F<INF>i = sampler flow rate for interval I n = number of flow intervals over the 24-hour period, excluding intervals of no flow rate during power interruptions. (ii) For each interval over the 24-hour period, calculate the difference between the interval sampler flow rate and the average sampler flow rate. The difference between the interval sampler flow rate and the average sampler flow rate must meet the flow rate regulation specification listed in Table E-2 of this subpart for all intervals during the 24-hour test period, excluding periods of electrical power interruption.
 (5) Sample flow rate coefficient of variation. (i) Using the sampler interval flow rates determined in paragraph (g)(3) of this section, calculate the sampler flow rate coefficient of variation, CV<INF>flow as: [GRAPHIC] [TIFF OMITTED] TP13DE96.064 Where CV<INF>flow = coefficient of variation of sampler flow rate, and F<INF>ave, F<INF>i, I, and n are as defined previously. (ii) The CV<INF>flow calculated must meet the sampler flow rate coefficient of variation specification listed in Table E-2 of this subpart for each test. Also the coefficient of variation reported by the sampler at the end of the sample period must agree with CV<INF>flow calculated here within 0.5%.
 (6) Flow rate measurement accuracy. (i)(A) Calculate the percent difference between the sampler flow rate, in actual liters per minute (L/min), indicated by the sampler, and the sampler flow rate measured with the flow rate test meter [paragraph (c)(3) of this section] in test procedures in paragraphs (f) (6)(i), (6)(iv), (6)(v), and (6)(vi) of this section, for each set of measurements as: [GRAPHIC] [TIFF OMITTED] TP13DE96.065 Where F<INF>si = sampler flow rate indicated by the sampler, in actual L/ min., for measurement set I. (B) All calculated sampler flow rate percent differences must meet the flow [[Page 65817]] rate measurement accuracy specification listed in Table E-2 of this subpart.
 (ii)(A) Obtain the value for the average sampler volumetric flow rate reported by the sampler at the end of the sample period and calculate the percent difference between the reported average sampler flow rate and the average flow rate determined in paragraph (f)(4) of this section as: [GRAPHIC] [TIFF OMITTED] TP13DE96.066 Where F<INF>s,ave = average sampler flow rate reported by the sampler. (B) This calculated percent difference must also meet the flow rate measurement accuracy specification listed in Table E-2 of this subpart. (7) Ambient temperature measurement accuracy. (i) Calculate the difference between the ambient air temperature indicated by the sampler and the ambient (chamber) air temperature measured with the ambient air temperature recorder, paragraph (c)(4) of this section, in test procedures paragraphs (f) (6)(ii), (6)(iv), and (6)(v) of this section, as: [GRAPHIC] [TIFF OMITTED] TP13DE96.067 Where T<INF>s = ambient air temperature indicated by the sampler, deg.C; and T<INF>m = ambient air temperature measured by the test temperature instrument, deg.C. (ii) All calculated temperature differences must meet the ambient air temperature measurement accuracy specification listed in Table E-2 of this subpart.
 (8) Ambient barometric pressure measurement accuracy. (i) Calculate the difference between the ambient barometric pressure indicated by the sampler and the ambient barometric pressure measured with the ambient barometric pressure meter, paragraph (c)(5) of this section, in test procedures in paragraphs (f)(6)(iii), (6)(v), and (6)(vi) of this section, as: [GRAPHIC] [TIFF OMITTED] TP13DE96.068 Where P<INF>s=ambient barometric pressure indicated by the sampler, mm Hg; and
 P<INF>m=ambient barometric pressure measured by the test barometric pressure meter, mm Hg. (ii) All calculated differences for barometric pressure must meet the ambient barometric pressure measurement accuracy specification listed in Table E-2 of this subpart.
 (9)(i) Filter temperature control (sampling). From the continuous record of the test sampler filter temperature obtained from the filter temperature sensor, paragraphs (c)(6) and (e)(4) of this section, in test procedure in paragraph (f)(5) of this section, determine the measured instantaneous or average filter temperature at intervals of not more than 5 minutes for the entire 24-hour sample period. From the continuous record of the ambient air temperature obtained from the ambient (chamber) air temperature recorder, paragraph (c)(4) of this section, in test procedure paragraph (f)(5) of this section, determine the measured instantaneous or average ambient (chamber) air temperature at intervals of not more than 5 minutes for the entire 24-hour sample period. For each interval over the 24-hour period (excluding intervals during power interruptions), calculate the difference, in deg.C, between the measured interval filter temperature and the measured interval ambient temperature for the corresponding interval, as: [GRAPHIC] [TIFF OMITTED] TP13DE96.069 (ii) The difference between the interval filter temperature and the interval average ambient temperature for all intervals must meet the filter temperature control specification listed in Table E-2 of this subpart, excluding periods of electrical power interruption. (10) Elapsed sample time accuracy. Calculate the sample time for the 24-hour sample period as the difference between the sample end time and the sample start time, as recorded in paragraph (f)(5) of this section, less the total time duration of all power interruptions. The difference between the actual sampler time calculated and the sample time reported by the sampler at the end of the sample period must meet the elapsed sample time accuracy specification listed in Table E-2 of this subpart.
 (11) Record of power interruptions. Verify that the sampler provides a visual display of the correct year, month, day-of-month, hour, and minute, within <plus-minus>2 minutes, of the start of each power interruption of more than 60 seconds. Sec. 53.53 Post-sampling filter temperature control test. (a) Overview. This procedure provides for testing the temperature control of the sample filter during the post-sampling (non-sampling) mode following sample collection. The test conditions and performance specifications are summarized in Table E-2 of this subpart. This performance parameter, when tested or determined as described in this test procedure, must meet or exceed the performance specification given in Table E-2 of this subpart for the associated PM<INF>2.5 method to be considered for designation as a reference or equivalent method. (b) Technical Definition. Post-sampling temperature control is the ability of a sampler to maintain the temperature of the particulate matter sample filter within the specified deviation from ambient temperature during the period between the end of active sample collection of the PM<INF>2.5 sample by the sampler until the filter is retrieved from the sampler for laboratory analysis. (c) Required test equipment. (1) Environmental chamber or other [[Page 65818]] temperature-controlled environment or environments, capable of obtaining and maintaining the various temperatures between -20 deg.C to +40 deg.C as required for the test with an accuracy of <plus-minus>2 deg.C. The test environment(s) must be capable of maintaining temperature within the specified limits continuously with the additional heat load of the operating test sampler in the environment. [Henceforth, where the test procedures specify a test or environmental ``chamber,'' an alternative temperature-controlled environmental area or areas may be substituted, provided the required test temperatures and all other test requirements are met. See Sec. 53.52(f)(1)].
 (2) Variable voltage ac power transformer, range 100 to 130 Vac, with sufficient VA capacity to operate the sampler continuously under test conditions.
 (3) Ambient air temperature recorder, range -30 deg.C to +50 deg.C, certified accurate to within 0.5 deg.C with a radiation error of 0.2 deg.C or less under a solar radiation intensity of 1000 watts/m2, as described in Reference 6 in Appendix A of this subpart. (4) Miniature temperature sensor, capable of being installed in the sampler without introducing air leakage and capable of measuring the sample air temperature within 1 cm of the center of the filter, downstream of the filter, certified accurate to within 0.5 deg.C, NIST traceable, with continuous (analog) recording capability or digital recording at intervals of not more than 5 minutes. (5) Means, such as a solar-spectrum lamp or lamps, for generating or simulating thermal radiation in approximate spectral content and intensity equivalent to solar insolation of 1000 watts/m2, inside the environmental chamber.
 (6) AC rms voltmeter, accurate to 0.5 volts. (7) Time measurement system, accurate to 10 seconds per day. (d) Calibration of test measurement instruments. Submit documentation showing evidence of recent calibration, calibration accuracy, and NIST-traceability (if required) of all measurement instruments used for the tests. Where an instrument's measurements are to be recorded with an analog recording device, the accuracy of the entire instrument-recorder system shall be calibrated or verified. (e) Test Setup. (1) The test sampler shall be set up for testing in the temperature-controlled chamber. Setup of the sampler shall be performed as described in the sampler's operation or instruction manual referred to in Sec. 53.4 (b)(3). The sampler shall be installed upright and set up in its normal configuration for collecting PM<INF>2.5 samples with a filter installed, except that the sample air inlet may be removed, if desired.
 (2) The sampler shall be provided ac line power from the variable voltage ac power transformer, which shall be set to provide power to the sampler at a voltage of 105 <plus-minus>1 volts ac (rms) during this test.
 (3) The miniature temperature sensor shall be installed in the test sampler such that it accurately measures the temperature of the air 1 cm from the center of the filter on the downstream side of the filter. (4) The solar radiant energy source shall be installed in the test chamber such that the entire test sampler is irradiated in a manner similar to the way it would be irradiated by solar radiation if it were located outdoors in an open area on a sunny day, with the radiation arriving at an angle of between 30 and 45 degrees from vertical and such that the intensity of the radiation received by all sampler surfaces that receive direct radiation is not less than 1000 watts/ m2 (measured in a plane perpendicular to the incident radiation). The incident radiation shall be oriented with respect to the sampler such that the area of the sampler's ambient temperature sensor (or temperature sensor shield) receives direct radiation as it would or could during normal outdoor installation. Also, the sensor must not be shielded from the radiation by a sampler part in a way that would not occur at other normal insolation angles or directions. (5) The ambient air temperature recorder shall be installed in the test chamber such that it will accurately measure the temperature of the air in the chamber without being unduly affected by the chamber's air temperature control system or by the radiant energy from the solar radiation that may be present inside the test chamber. (f) Procedure. (1) The test sampler shall be tested during operation in the post-sample collection operational mode (operation of the sampler during the period from the end of active sample collection of the PM<INF>2.5 sample by the sampler until the filter is retrieved from the sampler for laboratory analysis) over seven (7) hours, following one of the 24-hour tests described in Sec. 53.52. The test chamber temperature shall be initially set to <ls-thn-eq>-20 deg.C, raised to <gr-thn-eq>40 deg.C, held at <gr-thn-eq>40 deg.C for one hour, then reduced to <ls-thn-eq>-20 deg.C during the test. (2) Prepare the sampler for the test by allowing the sampler to operate for a normal 24-hour sample collection period, as directed in the sampler's operation or instruction manual. If the sampler has multiple (sequential) sample capability, any of the sequential channels may be used for the test; however, if the sampler has multiple filter holders, each filter holder must be tested for temperature control. Convenient start and stop times for a 24 <plus-minus> 0.1 hour sample collection period shall be set in the sampler to effect automatic sampler operation for each test period. The active sample collection period may start at any time of day and is not required to start at midnight. One or more of the test periods associated with test procedure set forth in Sec. 53.52 may be used for this test preparation.
 (3) At the beginning of the 7-hour test period, the solar insolation source, as described in paragraphs (c)(4) and (e)(4) of this section, shall be on, the ambient (chamber) temperature shall be set to <ls-thn-eq>-20 deg.C, and the sampler power line voltage shall be set to 105 <plus-minus>1 volts ac (rms). (4) During the 7-hour test period, continuously record the test chamber air temperature and the filter temperature, as measured by the test equipment in paragraph (c) of this section, either via a continuous analog recording or digital recording at intervals of not more than 5 minutes. Note and record the actual start and stop times for the sample period. The sampler power line voltage shall be measured during hours 1 and 7 of the test and at any other time during the test period when there is a possibility that the voltage may have changed. (5) During the first 3 hours of the test, the chamber air temperature shall be increased such that the chamber air temperature is <gr-thn-eq>40 deg.C 3 hours after the beginning of the test. The chamber air temperature shall be maintained at <gr-thn-eq>40 deg.C for one hour (until 4 hours after the beginning of the test), then decreased over the next 3 hours of the test such that the chamber air temperature is <ls-thn-eq>-20 deg.C at the end of the test (7 hours after the beginning of the test. The chamber air temperature profile during the first and last three hours of the test is unspecified, provided the initial, central hour, and final temperatures are as specified in paragraph (f)(1) of this section. (g) Test Results--(1) Filter temperature control (post-sampling). From the continuous record of the test sampler filter temperature obtained from the filter temperature sensor, paragraphs (c)(3) and (e)(3) of this section, determine the measured instantaneous or average filter temperature at intervals of not more than 5 minutes for the entire 7-hour test [[Page 65819]] period. From the continuous record of the ambient air temperature obtained from the ambient (chamber) air temperature recorder, paragraphs (c)(4) and (e)(5) of this section, determine the measured instantaneous or average ambient (chamber) air temperature at the same intervals used for filter temperature for the entire 7-hour sample period. For each interval over the 7-hour period, calculate the difference, in deg.C, between the measured interval filter temperature and the measured interval ambient temperature for the corresponding interval, as: [GRAPHIC] [TIFF OMITTED] TP13DE96.070 (2) The difference between the interval filter temperature and the interval average ambient temperature for each and all intervals must meet the filter temperature control specification listed in Table E-2 of this subpart, excluding periods of electrical power interruption, if any. Sec. 53.54 Leak check test. (a) Overview. Under section 7.4.6 of Appendix L of part 50 of this chapter, the sampler is required to include a facility--including components, instruments, operator controls, a written procedure, and other capabilities as necessary--to allow the operator to carry out a leak test of the sampler at a field monitoring site without additional equipment. This procedure is intended to test the adequacy and effectiveness of the sampler's leak check facility. Because of the variety of potential sampler configurations and leak check procedures possible, some adaptation of this procedure may be necessary to accommodate the specific sampler under test. (b) Technical definitions. (1) External leakage includes the total flow rate of external ambient air which enters the sampler other than through the sampler inlet and which passes through any one or more of the impactor, filter, or flow rate measurement components. (2) Internal leakage is the total sample air flow rate that passes through the filter holder assembly without passing through the sample filter.
 (c) Required test equipment.
 (1) Flow rate measurement device, range 70 to 130 mL/min, 2 percent certified accuracy, NIST-traceable.
 (2) Flow control device, capable of providing a controlled, simulated leak flow rate of 100 mL/min. (3) Flow rate measurement adaptor (Drawing L-27, Appendix L of part 50 of this chapter) or equivalent adaptor to facilitate measurement of sampler flow rate.
 (4) A disk, such as a sample filter that is heavily loaded or a flow-impervious membrane containing one or more pinholes, which can be installed into the sampler's filter cassette (either with or without a normal sample filter) and which blocks the normal flow rate through the filter cassette but which, instead, provides a simulated leak flow rate through the disk of not more than 100 mL/min under the conditions specified for the leak check in the sampler's leak check procedure. (d) Calibration of test measurement instruments. Submit documentation showing evidence of recent calibration, calibration accuracy, and NIST-traceability (if required) of all measurement instruments used in the tests. The accuracy of flow meters shall be verified at the highest and lowest pressures and temperatures used in the tests and shall be checked at zero and one or more non-zero flow rates within 7 days of test use.
 (e) Test setup. (1) The test sampler shall be set up for testing as described in the sampler's operation or instruction manual referred to in Sec. 53.4(b)(3). The sampler shall be installed upright and set up in its normal configuration for collecting PM<INF>2.5 samples, except that the sample air inlet shall be removed and a device such as a flow rate measurement adaptor shall be installed on the sampler's downtube. (2) The flow rate control device shall be set up to provide a constant, controlled flow rate of 100 mL/min into the sampler downtube under the conditions specified for the leak check in the sampler's leak check procedure.
 (3) The flow rate measurement device shall be set up to measure the controlled flow rate of 100 mL/min into the sampler downtube under the conditions specified for the leak check in the sampler's leak check procedure.
 (f) Procedure. (1) Install a sample filter in the test sampler and ensure that the sampler has no internal or external leaks. (2) Carry out both the external and internal leak check procedure as described in the sampler's operation/instruction manual and verify that both leak checks indicate no significant leaks in the test sampler.
 (3) Arrange the flow control device, flow rate measurement device, and other apparatus as necessary to provide a simulated leak flow rate of 100 mL/min into the test sampler through the downtube during the specified external leak check procedure. Carry out the external leak check procedure as described in the sampler's operation/instruction manual but with the simulated leak of 100 mL/min. (4) Install the disk that simulates a filter-bypass leak in the filter cassette and carry out the internal leak check procedure as described in the sampler's operation/instruction manual. (g) Test results. The requirements for successful passage of this test are:
 (1) That the leak check procedure indicates no significant external or internal leaks in the test sampler when no simulated leaks are introduced.
 (2) That the external leak check procedure properly identifies the simulated external leak of 100 mL/min.
 (3) That the internal leak check procedure properly identifies the simulated internal leak of 100 mL/min. Sec. 53.55 Flow rate cut-off test. (a) Overview. This test is intended to verify that the sampler carries out the required automatic sample flow rate cut-off function properly.
 (b) Technical definition. The flow rate-cut off function requires the sampler to automatically stop sample flow and terminate the current sample collection if the sample flow rate becomes less than the minimum flow rate specified in Table E-2 of this subpart (10 percent below the nominal sample flow rate) for more than 60 seconds during a sample collection period.
 (c) Required test equipment. (1) Flow rate meter, suitable for measuring the sampler flow rate at the sampler inlet in a closed system below atmospheric pressure, range 10 to 25 actual L/min, 2 percent certified accuracy, NIST-traceable, with continuous (analog) recording capability or digital recording at intervals of not more than 5 seconds. Mass flow meter type recommended; however, note that temperature and pressure corrections are generally required to convert measured mass flow rate to actual volumetric flow rate. (2) Valve or other means to restrict or reduce the sample flow rate.
 (d) Calibration of test measurement instruments. Submit documentation showing evidence of recent calibration, calibration accuracy, and NIST-traceability of the flow rate meter used for this test. The accuracy of the flow meter shall be verified at the highest [[Page 65820]] and lowest pressures used in the tests and shall be checked at zero and one or more non-zero flow rates within 7 days of test use. Where an instrument's measurements are to be recorded with an analog recording device, the accuracy of the entire instrument-recorder system shall be calibrated or verified.
 (e) Test setup. (1) The test sampler shall be set up for testing at any temperature and barometric pressure within the specified ranges. Setup of the sampler shall be performed as described in the sampler's operation or instruction manual referred to in Sec. 53.4(b)(3). The sampler shall be installed upright and set up in its normal configuration for collecting PM<INF>2.5 samples, except that the sample air inlet shall be removed to permit measurement of the sampler flow rate by the certified flow rate meter.
 (2) The flow rate meter shall be connected so as to measure the sampler flow rate at the entrance to the sampler (i.e. the flow rate that would enter the sampler inlet if the inlet had not been removed). (3) The valve or means for reducing sampler flow rate shall be installed such that the sampler flow rate can be manually restricted during the test.
 (f) Procedure. (1) Prepare the sampler for normal sample collection operation as directed in the sampler's operation or instruction manual. Set the sampler to automatically start a normal 24-hour sampler collection period at a convenient time. (2) Continuously record the sampler flow rate and the time during the sample period, with at least 5-minute resolution during the normal operation of the sampler and at least 5-second resolution during the time period when the sampler flow rate is manually reduced. (3) After at least 1 hour of normal sampler operation at a sample flow rate within the specified flow rate range specified in Table E-2 of this subpart, manually restrict the sampler flow rate such that the sampler flow rate is decreased slowly over several minutes to a flow rate less than the flow rate cut off value specified in Table E-2 of this subpart. Maintain this flow rate for at least 2.0 minutes or until the sampler stops the sample flow automatically. (g) Test Results. (1) Inspect the continuous record of the sampler flow rate and determine the time at which the sampler flow rate decreases to a value less than the cut-off value specified in Table E-2 of this subpart. To pass this test, the sampler must automatically stop the sampler flow at least 30 seconds but not more than 50 seconds after the time at which the sampler flow rate was determined to have decreased to a value less than the value specified in Table E-2 of this subpart.
 (2) Verify that the elapsed sample time and average flow rate reported by the sampler for this test sample period are accurate within 2 percent. The sampler must provide the same information to the operator as is required following a normal sample collection period, and the information reported in this test must accurately reflect the substantially shortened sample collection period caused by the automatic sample flow cut off.
 (3) Verify that the sampler's required ``Flow-out-of-spec'' and the ``Incorrect sample period'' flag indicators are set at the end of the test. Sec. 53.56 Operational field precision test. (a) Overview. This test is intended to determine the operational precision of the candidate sampler during a minimum of 10 days of field operation, using three collocated test samplers. Measurements of PM<INF>2.5 are made with all of the samplers and then compared to determine replicate precision. This procedure is applicable to both reference and equivalent methods. In the case of equivalent methods, this test may be combined and conducted concurrently with the comparability test for equivalent methods (subpart C of this part), using three reference method samplers collocated with three candidate equivalent method samplers and meeting the applicable site and other requirements of subpart C of this part. (b) Technical definition. Field precision means the standard deviation or relative standard deviation of a set of measurements obtained concurrently with three or more collocated samplers in actual ambient air field operation.
 (c) Test site. Any outdoor test site having PM<INF>2.5 concentrations that are reasonably uniform over the test area and that meet the minimum level requirement of Sec. 53.56(g) is acceptable for this test.
 (d) Required facilities and equipment. An appropriate test site and suitable electrical power to accommodate three test samplers. (e) Test setup. (1) Three identical test samplers shall be installed at the test site in their normal configuration for collecting PM<INF>2.5 samples in accordance with the instructions in the associated manual referred to in Sec. 53.4(b)(3) and in accordance with applicable supplemental guidance provided in Reference 3 in Appendix A of this subpart. The test sampler inlet openings shall be located at the same height above ground and between 2 and 4 meters apart horizontally. The samplers shall be arranged or oriented in a manner that will minimize spatial and wind directional effects on sample collection of one sampler on the other samplers. (2) Each test sampler shall be leak checked, calibrated, and set up for normal operation in accordance with the instruction manual and with any applicable supplemental guidance provided in Reference 3 in Appendix A of this supbart.
 (f) Test procedure. (1) Install a specified filter in each sampler and otherwise prepare each sampler for normal sample collection. Set identical sample collection start and stop times for each sampler. (2) Collect either a 24-hour or a 48-hour atmospheric PM<INF>2.5 sample simultaneously with each of the three test samplers. (3) Determine the measured PM<INF>2.5 mass concentration for each sample in accordance with the procedures prescribed for the candidate method in the associated manual referred to in Sec. 53.4(b)(3) and in accordance with supplemental guidance in Reference 3 in Appendix A of this subpart.
 (4) Repeat this procedure to obtain a total of 10 sets of 24-hour or 48-hour PM<INF>2.5 measurements over 10 test periods. (g) Calculations. (1) Record the PM<INF>2.5 concentration for each test sampler for each test day as C<INF>i,j, where I is the sampler number (I=1,2,3) and j is the test day (j=1,2, . . . 10). (2) For each test day, calculate and record the average of the three measured PM<INF>2.5 concentrations as C<INF>j where j is the test day: [GRAPHIC] [TIFF OMITTED] TP13DE96.071 If C<INF>j<10 <greek-m>g/m\3\ for any test day, data from that test day are unacceptable and an additional sample collection set must be performed to replace the unacceptable data. (3) Calculate and record the precision for each of the 10 test days as: [[Page 65821]] [GRAPHIC] [TIFF OMITTED] TP13DE96.072 if C<INF>j is below 40 <greek-m>g/m\3\ for 24-hour measurements or below 30 <greek-m>g/m\3\ for 48-hour measurements; or [GRAPHIC] [TIFF OMITTED] TP13DE96.073 if C<INF>j is above 40 <greek-m>g/m3 for 24-hour measurements or above 30 <greek-m>g/m3 for 48-hour measurements. (h) Test results. The candidate method passes the precision test if all 10 P<INF>j or RP<INF>j values meet the specifications in Table E-2 of this subpart. Sec. 53.57 Aerosol transport test for class I sequential samplers (a) Overview. This test is intended to verify adequate aerosol transport through any air flow splitting components that may be used in a Class I candidate equivalent method sampler to achieve sequential sampling capability. This test is applicable to all Class I candidate samplers in which the aerosol flow path (the flow of air upstream of filtration) differs from that specified for reference method samplers as set forth in Drawings L-18 and L-24 of Appendix L to part 50 of this chapter. This test does not apply to candidate Class I equivalent method samplers in which each channel consists of a separate inlet, impactor, and filter holder of the exact same internal geometry as specified for the reference method sampler. The test requirements and performance specifications for this test are summarized in Table E-1 of this subpart.
 (b) Technical Definitions. (1) Aerosol transport is the percentage of the laboratory challenge aerosol which penetrates to the active sample filter of the candidate Class I sampler. (2) The active sample filter is the exclusive filter through which air is flowing during performance of this test. (3) A no-flow filter is a sample filter through which no air is flowing during performance of this test. (4) A channel is a flow path that the aerosol make take, only one of which may be active at a time.
 (5) An added component is any physical part of the sampler which is different from that specified for the reference method sampler and which allows or causes the aerosol to be routed to a different channel. (c) Required facilities and test equipment. (1) Aerosol generation system, as specified in Sec. 53.64(c)(1). (2) Aerosol delivery system, as specified in Sec. 53.64(c)(2). (3) Particle size verification equipment, as specified in Sec. 53.64(c)(3).
 (4) Fluorometer, as specified in Sec. 53.64(c)(4). (5) Candidate sampler, with the inlet and impactor or impactors removed, and with all internal surfaces of added components electroless nickel coated as specified in Sec. 53.64(d)(5) (d) Calibration of test measurement instruments. Submit documentation showing evidence of recent calibration, calibration accuracy, and NIST-traceability (if required) of all measurement instruments used for the tests. Where an instrument's measurements are to be recorded with an analog recording device, the accuracy of the entire instrument-recorder system shall be calibrated or verified. (e) Test setup. (1) The candidate sampler, with its inlet and impactor(s) removed, shall be installed in the particle delivery system so that the test aerosol is introduced at the top of the downtube that connects to the exit adaptor of the inlet. If the candidate sampler has a separate impactor for each channel, then for this test the filter holder assemblies must be connected to the physical location on the sampler where the impactors would normally connect. (2) Filters that are appropriate for use with fluorometric methods (e.g., glass fiber) shall be used for particle collection for these tests.
 (f) Procedure. (1) All surfaces of the added component(s) which come in contact with the aerosol flow shall be thoroughly washed with 0.01 N NaOH and then dried.
 (2) Generate aerosol composed of oleic acid with a uranine fluorometric tag of 4 <greek-m>m <plus-minus>0.25 <greek-m>m using a vibrating orifice aerosol generator according to procedures specified in Sec. 53.61(g). Check for the presence of satellites and adjust the generator to minimize their production. Calculate the aerodynamic particle size using the operating parameters of the vibrating orifice aerosol generator and record. The calculated aerodynamic diameter must be within 0.25 <greek-m>m of 4 <greek-m>m. (3) Verify the particle size according to procedures specified in Sec. 53.62(d)(4)(i).
 (4) Collect particles on filters for a time period such that the relative error of the measured fluorometric concentration in the active filter is less than 5 percent.
 (5) Determine the quantity of material collected on the active filter using a calibrated fluorometer. Record the mass of fluorometric material for the active filter as M<INF>active(I) where I = active channel number.
 (6) Determine the quantity of material collected on the no-flow filter(s) using a calibrated fluorometer. Record the mass of fluorometric material on each no-flow filter as M<INF>no-flow(ij) where I = active channel number and j = no-flow filter number. (7) Wash the surfaces of the added component(s) which contact the aerosol flow with 0.01N NaOH and determine the quantity of material collected using a calibrated fluorometer. Record the mass of fluorometric material collected in the wash as M<INF>wash(I), where I = replicate number. [[Page 65822]] (8) Calculate and record the aerosol transport as: [GRAPHIC] [TIFF OMITTED] TP13DE96.074 where I = active channel number and j = no-flow filter number. (9) Repeat paragraphs (f) (1) through (6) of this section for each channel, making each channel in turn the exclusive active channel. (g) Evaluation of test results. The candidate Class I sampler passes the aerosol transport test if the specification in Table E-1 of this subpart is met for each channel. Tables to Subpart E of Part 53 Table E-1--Test Conditions for Sec. 53.52 Comprehensive 24-Hour Tests
 
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 Initial Final 
 Power Line temperature temperature,
```
 24-hour test number voltage Deg C, Hours Deg. C, Hours
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 1-8 22-24 
```
 1............................ 105 <plus- <ls-thn-eq>-2 15.0 <plusminus>
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 1 0.0 minus>2.0 
```
 2............................ 125 <plus- 15.0 <plus- <gr-thn-eq>40
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 minus>1 minus>2.0 .0 
```
 3............................ 125 <plus- <gr-thn-eq>40 15.0 <plusminus>
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 1 .0 minus>2.0 
```
 4............................ 105 <plus- 15.0 <plus- <ls-thn-eq>-2
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 minus>1 minus>2.0 0.0 
```
 BILLING CODE 6560-50-P [[Page 65823]] [GRAPHIC] [TIFF OMITTED] TP13DE96.075 [[Page 65824]] Figures to Subpart E
 [GRAPHIC] [TIFF OMITTED] TP13DE96.076 [[Page 65825]] [GRAPHIC] [TIFF OMITTED] TP13DE96.077 [[Page 65826]] [GRAPHIC] [TIFF OMITTED] TP13DE96.078 [[Page 65827]] Appendix A to Subpart E of Part 53--References
 1. ``Quality systems--Model for quality assurance in design, development, production, installation and servicing,'' ISO9001. July
 2. Available from American Society for Quality Control, 611 East Wisconsin Avenue, Milwaukee, WI 53202.
 3. ``American National Standard--Specifications and Guidelines for Quality Systems for Environmental Data Collection and Environmental Technology Programs.'' ANSI/ASQC E4-1994. January
 4. Available from American Society for Quality Control, 611 East Wisconsin Avenue, Milwaukee, WI 53202.
 5. Quality Assurance Handbook for Air Pollution Measurement Systems, Volume II, Ambient Air Specific Methods (Interim Edition), section 2.12. EPA/600/R-94/038b, April 1994. Available from CERI, ORD Publications, U.S. Environmental Protection Agency, 26 West Martin Luther King Drive, Cincinnati, Ohio 45268. [Section 2.12 is currently under development and will not be available from the previous address until it is published as an addition to EPA/600/R- 94/038b. Prepublication draft copies of section 2.12 will be available from Department E (MD-77B), U.S. EPA, Research Triangle Park, NC 27711 or from the contact identified at the beginning of this proposed rule].
 6. Military standard specification (mil. spec.) 8625F, Type II, Class 1 as listed in Department of Defense Index of Specifications and Standards (DODISS), available from DODSSP-Customer Service, Standardization Documents Order Desk, 700 Robbins Avenue, Building 4D, Philadelphia, PA 1911-5094.
 7. ``Guidance for the Use and Application of Designation Testing and Sampler Manufacturing Checklists, as Required under 40 CFR 53.51'' U.S. EPA Publication No. [To be prepared.]
 8. Quality Assurance Handbook for Air Pollution Measurement Systems, Volume IV: Meteorological Measurements. Revised March,
 9. EPA-600/R-94-038d. Available from U.S. EPA, ORD Publications Office, Center for Environmental Research Information (CERI), 26 West Martin Luther King Drive, Cincinnati, Ohio 45268-1072 (513-569- 7562).
 10. Subpart F is added to read as follows: Subpart F--Procedures for Testing Performance Characteristics of Class II Equivalent Methods for PM<INF>2.5 Sec.
 53.60 General provisions.
 53.61 Test conditions for PM<INF>2.5 reference method equivalency. 53.62 Test procedures: Full wind tunnel test. 53.63 Test procedures: Wind tunnel inlet aspiration test. 53.64 Test procedures: Static fractionator test. 53.65 Test procedures: Loading test.
 53.66 Test procedures: Volatility test. Tables to Subpart F of Part 53 Table F-1 Performance Specifications for PM<INF>2.5 Class II Equivalent Samplers
 Table F-2 Particle Size and Wind Speeds for Full Wind Tunnel Evaluation, Wind Tunnel Inlet Aspiration Test, and Statics Chamber Test
 Table F-3 Critical Parameters of Idealized Ambient Particle Size Distributions
 Table F-4 Estimated Mass Concentration of PM<INF>2.5 for Idealized Coarse Aerosol Size Distribution
 Table F-5 Estimated Mass Concentration Measurement of PM<INF>2.5 for Idealized ``Typical'' Coarse Aerosol Size Distribution Table F-6 Estimated Mass Concentration Measurement of PM<INF>2.5 for Idealized Fine Aerosol Size Distribution Figures to Subpart F of Part 53 Figure F-1 Flowchart for Determining Requirements for Class II Samplers Equivalent
 Figure F-2 Designation Testing Checklist Appendix A to Subpart F of Part 53--References Subpart F--Procedures for Testing Performance Characteristics of Class II Equivalent Methods for PM<INF>2.5 Sec. 53.60 General provisions. (a) This subpart sets forth the specific requirements that a PM<INF>2.5 sampler associated with a candidate Class II equivalent method must meet to be designated as an equivalent method for PM<INF>2.5. This subpart also sets forth the explicit test procedures that must be carried out and the test results, evidence, documentation, and other materials that must be provided to EPA to demonstrate that a sampler meets all specified requirements for designation as an equivalent method.
 (b) A candidate method described in an application for a reference or equivalent method application submitted under Sec. 53.4 shall be determined by the EPA to be a Class II candidate equivalent method on the basis of the definition of a Class II equivalent method given in Sec. 53.1.
 (c) Any sampler associated with a Class II candidate equivalent method (Class II sampler) must meet all requirements for reference method samplers or Class I equivalent method samplers specified in subpart E of this part, as appropriate. In addition, a Class II sampler must meet the additional requirements as specified in Sec. 53.60(d) of this part.
 (d) Except as provided in paragraph (d) (1), (2) and (3) of this section, all Class II samplers are subject to the additional tests and performance requirements specified in Sec. 53.62 (full wind tunnel test), Sec. 53.65 (loading test), and Sec. 53.66 (volatility test). Alternative tests and performance requirements, as described in paragraphs (d) (1), (2), and (3) of this section, are optionally available for certain Class II samplers which meet the requirements for reference method or Class I samplers given in Appendix L of part 50 of this chapter and in Subpart E of this part, except for specific deviations of the inlet, fractionator, or filter. These requirements and the exceptions in paragraphs (d) (1), (2), and (3) of this section are summarized in the flowchart given in Figure F-1 of this subpart. (1) Inlet deviation. A sampler which has been determined to be a Class II sampler (rather than a reference method or Class II sampler) solely because the design or construction of its inlet deviates from the design or construction of the inlet specified in Appendix L for reference method samplers shall not be subject to the requirements of Sec. 53.62 (full wind tunnel test), provided that it meets all requirements of Sec. 53.63 (inlet aspiration test), Sec. 53.65 (loading test), and Sec. 53.66 (volatility test). (2) Fractionator deviation. A sampler which has been determined to be a Class II sampler solely because the design or construction of its particle size fractionator deviates significantly from the design or construction of the particle size fractionator specified in 40 CFR part 50, Appendix L for reference method samplers shall not be subject to the requirements of Sec. 53.62 (full wind tunnel test), provided that it meets all requirements of Sec. 53.64 (static fractionator test), Sec. 53.65 (loading test), and Sec. 53.66 (volatility test). (3) Filter size deviation. A sampler which has been determined to be a Class II sampler solely because the size of its sample collection filter deviates from the sampler filter size specified in Appendix L for reference method samplers shall not be subject to the requirements of Sec. 53.62 (full wind tunnel test) nor Sec. 53.65 (loading test), provided it meets all requirements of Sec. 53.66 (volatility test). (e) The test specifications and acceptance criteria for each test are summarized in Table F-1 of this subpart. The candidate sampler must demonstrate performance that meets the acceptance criteria for each applicable test to be designated as an equivalent method. (f) Overview of various test procedures for Class II samplers. (1) Full wind tunnel test. This test procedure is designed to ensure that the candidate sampler's aspiration of an ambient aerosol and penetration of the sub 2.5-micron fraction to its sample filter will be comparable to that of a reference method sampler. The test conditions are [[Page 65828]] summarized in Table F-2 of this subpart (under the heading, ``Full Wind Tunnel Test'), and the candidate sampler must meet the acceptance criteria specified in Table F-1 of this subpart. (2) Wind tunnel inlet test. The wind tunnel inlet aspiration test challenges the candidate sampler with a monodisperse aerosol that is specified in Table F-2 of this subpart (under the heading, ``Inlet Aspiration Test'). The aerosol is introduced into a wind tunnel environment, and the aspiration of the candidate sampler is compared with that of the reference method sampler at wind speeds of 2 km/hr and 24 km/hr. The acceptance criteria presented in Table F-1 of this subpart is based on the relative aspiration between the candidate sampler and federal reference method sampler. (3) Static 2.5-micron fractionator test. The static 2.5-micron fractionator test determines the effectiveness of the candidate fractionator under static conditions for aerosols of the size and type specified in Table F-2 of this subpart (under the heading, ``Static Fractionator Test'). The candidate sampler must meet the acceptance criteria presented in Table F-1 of this subpart. (4) Loading test. (i) The loading test is used to ensure that the performance of a candidate sampler is not significantly affected by the amount of material deposited on its interior surfaces between periodic cleaning. This test is divided into two distinct experiments: (A) A mandatory demonstration of no significant performance shift over a 24-hour time period; and
 (B) An optional demonstration of no significant performance shift over an extended time period for approval of a cleaning interval greater than 24 hours.
 (ii) In the initial evaluation, the candidate sampler is operated in test environment equivalent to sampling 150 <greek-m>g/m3 coarse mode aerosol over a 24-hour time period. The candidate's performance must then be evaluated by Sec. 53.62 (full wind tunnel evaluation) with the exception being a modification to the fractionator alone, in which case the performance may be optionally evaluated by Sec. 53.64 (static fractionator test). If the results of the appropriate test meet the criteria presented in Table F1 of this subpart, then the candidate sampler passes the loading test under the condition that it be cleaned after each 24-hour use. (iii) An extended loading test may be performed to gain approval of a longer time period between periodic cleaning of the fractionator. In this extended loading test, the candidate sampler is loaded with a mass equivalent to operating the unit in an environment of 150 <greek-m>g/ m3 coarse mode aerosol over the time period proposed by the manufacturer between cleaning. Reevaluation of the expected mass collected is performed via the wind tunnel test or the static 2.5- micron fractionator test, depending upon which test was used for the initial evaluation. If the results meet the criteria presented in Table F-1 of this subpart, then the candidate sampler passes the loading test under the condition that it be cleaned at least as often as the proposed cleaning frequency.
 (5) Volatility test. The volatility test challenges the candidate sampler with a polydisperse, semi-volatile liquid aerosol. This aerosol is simultaneously sampled by the candidate method sampler and a reference method sampler for a specified time period. Clean air is then passed through the samplers for an additional time period. The filters are then reweighed to determine residual mass of the collected aerosol. The candidate sampler passes the volatility test if the candidate method meets the specifications presented in Table F-1 of this subpart. (g) Test data. All test data and other documentation obtained from or pertinent to these tests shall be identified, dated, signed by the analyst performing the test, and submitted to EPA as part of the equivalent method application. Schematic drawings of each particle delivery system and other information showing complete procedural details of the test atmosphere generation, verification, and delivery techniques for each test performed shall be submitted to EPA. All pertinent calculations shall be clearly presented. In addition, manufacturers are required to complete and submit the designation testing checklist presented in Figure 2 of this subpart as part of the application. Sec. 53.61 Test conditions. (a) Sampler surface preparation. Internal surfaces of the candidate sampler shall be cleaned and dried prior to performing any Class II sampler test in this Subpart. The internal collection surfaces of the sampler shall then be prepared in strict accordance with the operating instructions specified in the sampler's operating manual referred to in Sec. 53.4(b)(3).
 (b) Sampler setup. Set up and start up of all test samplers shall be in strict accordance with the operating instructions specified in the manual referred to in Sec. 53.4(b)(3), unless otherwise specified within this subpart.
 (c) Sampler adjustments. Once the test sampler or samplers have been set up and the performance tests started, manual adjustment shall be permitted only between test points for all applicable tests. Manual adjustments and any periodic maintenance shall be limited to only those procedures prescribed in the manual referred to in Sec. 53.4(b)(3). The submitted records shall clearly indicate when any manual adjustment or periodic maintenance was made and shall describe the operations performed.
 (d) Sampler malfunctions. If a test sampler malfunctions during any of the applicable tests that test run shall be repeated. A detailed explanation of all malfunctions and the remedial actions taken shall be submitted as part of the equivalent method application. (e) Particle concentration measurements. All measurements of particle concentration must be made such that the relative error in measurement is less than 5.0 percent. Relative error is defined as (s x 100 percent)/(X), where s is the sample standard deviation of the particle concentration detector, X is the measured concentration, and the units of s and X are identical.
 (f) Operation of test measurement equipment. All test measurement equipment shall be setup, calibrated, and maintained according to the manufacturer's instructions by qualified personnel only. All appropriate calibration information and manuals for this equipment shall be kept on file.
 (g) Aerosol generation parameters. This section prescribes conventions regarding aerosol generation techniques. Size-selective performance tests outlined in Secs. 53.62, 53.63, 53.64, and 53.65 specify the use of the vibrating orifice aerosol generator (VOAG) for the production of test aerosols. The volatility test in Sec. 53.66 specifies the use of a nebulized polydisperse aerosol. (1) Particle aerodynamic diameter. The VOAG produces nearmonodisperse droplets through the controlled breakup of a liquid jet. When the liquid solution consists of a non-volatile solute dissolved in a volatile solvent, the droplets dry to form particles of nearmonodisperse size.
 (i) The physical diameter of a generated spherical particle can be calculated from the operating parameters of the VOAG as: [GRAPHIC] [TIFF OMITTED] TP13DE96.079 where: D<INF>p=particle physical diameter, <greek-m>m Q=liquid volumetric flow rate, <greek-m>m3/sec [[Page 65829]] C<INF>vol=volume concentration (particle volume produced per drop volume), dimensionless
 f=frequency of applied vibrational signal, sec-1. (ii) A given particle's aerodynamic behavior is a function of its physical particle size, particle shape, and density. Aerodynamic diameter is defined as the diameter of a unit density (<greek-r><INF>o=1 g/m3) sphere having the same settling velocity as the particle under consideration. For converting a spherical particle of known density to aerodynamic diameter, the governing relationship is: [GRAPHIC] [TIFF OMITTED] TP13DE96.080 where D<INF>ae=particle aerodynamic diameter, <greek-m>m <greek-r><INF>p=particle density, g/cm3 <greek-r><INF>o=aerodynamic particle density=1 g/m3 C<INF>Dp=Cunningham's slip correction factor for physical particle diameter, dimensionless
 C<INF>Dae=Cunningham's slip correction factor for aerodynamic particle diameter, dimensionless. (iii) At room temperature and standard pressure, the Cunningham's slip correction factor is solely a function of particle diameter: [GRAPHIC] [TIFF OMITTED] TP13DE96.081 or
 [GRAPHIC] [TIFF OMITTED] TP13DE96.082 (iv) Since the slip correction factor is itself a function of particle diameter, the aerodynamic diameter cannot be solved directly but can be determined by iteration.
 (2) Solid particle generation. As specified in Table F-2 of this subpart, all solid particle tests in this subpart shall be conducted using particles composed of ammonium fluorescein. For use in the VOAG, liquid solutions of known volumetric concentration can be prepared by diluting fluorescein powder (C<INF>20H<INF>12O<INF>5, FW=332.31, CAS 2321-07-5) with aqueous ammonia. Guidelines for preparation of fluorescein solutions of the desired volume concentration (C<INF>vol) are presented by Vanderpool and Rubow (1988) (Reference 2 in Appendix A of this subpart). For purposes of converting particle physical diameter to aerodynamic diameter, an ammonium fluorescein density of 1.35 g/ cm3 shall be used. Mass deposits of ammonium fluorescein shall be extracted and analyzed using solutions of 0.01 N ammonium hydroxide. (3) Liquid particle generation. (i) Oleic acid particles. (A) Tests prescribed in Sec. 53.63 for inlet aspiration require the use of liquid particle tests composed of oleic acid tagged with uranine to enable subsequent fluorometric quantitation of collected aerosol mass deposits. Oleic acid (C<INF>18H<INF>34O<INF>2, FW=282.47, CAS 112-80-1) has a density of 0.8935 g/cm3. Because the viscosity of oleic acid is relatively high, significant errors can occur when dispensing oleic acid using volumetric pipettes. For this reason, it is recommended that oleic acid solutions be prepared by quantifying dispensed oleic acid gravimetrically. The volume of oleic acid dispensed can then be calculated simply by dividing the dispensed mass by the oleic acid density.
 (B) Oleic acid solutions tagged with uranine shall be prepared as follows. A known mass of oleic acid shall first be diluted using absolute ethanol. The desired mass of the uranine tag should then be diluted in a separate container using absolute ethanol. Uranine (C<INF>20H<INF>10O<INF>5Na<INF>2, FW=376.3, CAS 518-47-8) is the disodium salt of fluorescein and has a density of 1.53 g/cm3. In preparing uranine tagged oleic acid particles, the uranine content shall not exceed 20 percent on a mass basis. Once both oleic acid and uranine solutions are properly prepared, they can then be combined and diluted to final volume using absolute ethanol. (C) Calculation of the physical diameter of the particles produced by the VOAG requires knowledge of the liquid solution's volume concentration (C<INF>vol). Because uranine is essentially insoluble in oleic acid, the total particle volume is the sum of the oleic acid volume and the uranine volume. The volume concentration of the liquid solution shall be calculated as: [GRAPHIC] [TIFF OMITTED] TP13DE96.083 where: V<INF>u=uranine volume, ml
 V<INF>oleic=oleic acid volume, ml V<INF>sol=total solution volume, ml M<INF>u=uranine mass, g
 <greek-r><INF>u=uranine density, g/cm3 M<INF>oleic=oleic acid mass, g
 <greek-r><INF>oleic=oleic acid density, g/cm3 (D) For purposes of converting the particles' physical diameter to aerodynamic diameter, the density of the generated particles shall be calculated as: [GRAPHIC] [TIFF OMITTED] TP13DE96.084 [[Page 65830]] (E) Mass deposits of oleic acid shall be extracted and analyzed using solutions of 0.01 N sodium hydroxide. (ii) Glycerol. Tests prescribed in Sec. 53.66 for conducting volatility tests shall be conducted using ACS reagent grade glycerol (C<INF>3H<INF>8O<INF>3, FW=92.09, CAS 56-81-5) with a minimum purity of 99.5 percent. Sec. 53.62 Test Procedure: Full wind tunnel test. (a) Overview. The full wind tunnel test evaluates the effectiveness of the candidate sampler at 2 km/hr and 24 km/hr for aerosols of the size and type specified in Table F-2 of this subpart (under the heading, ``Full Wind Tunnel Test''). For each wind speed, a smooth curve is fit to the effectiveness data and corrected for the presence of multiplets in the wind tunnel calibration aerosol. The cutpoint diameter (Dp<INF>50) at each wind speed is then be determined from the corrected effectiveness curves. The two resultant penetration curves are then numerically integrated with three idealized ambient particle size distributions to provide an estimate of measured mass concentration. Critical parameters for these idealized distributions are presented in Table F-3 of this subpart. (b) Technical definitions. Effectiveness is the ratio (expressed as a percentage) of the mass concentration of particles of a specific size reaching the sampler filter or filters to the mass concentration of particles of the same size approaching the sampler. (c) Facilities and equipment required. (1) Wind tunnel. The particle delivery system shall consist of a blower system and a wind tunnel having a test section of sufficiently large cross-sectional area such that the test sampler, or portion thereof, as installed in the test section for testing, blocks no more than 15 percent of the test section area. The wind tunnel blower system must be capable of maintaining uniform wind speeds at the 2 km/hr and 24 km/hr. (2) Aerosol generation system. A vibrating orifice aerosol generator shall be used to produce monodisperse solid particles of ammonium fluorescein with equivalent aerodynamic diameters as specified in Table F-2 of this subpart. The geometric standard deviation for each particle size and type generated shall not exceed 1.1 (for primary particles) and the proportion of multiplets (doublets and triplets) in all test particle atmosphere shall not exceed 10 percent. The aerodynamic particle diameter, as established by the operating parameters of the vibrating orifice aerosol generator, shall be within the tolerance specified in Table F-2 of this subpart. (3) Particle size verification equipment. The size of the test particles shall be verified during this test by use of a suitable instrument (e.g., scanning electron microscope, optical particle counter, time-of-flight apparatus). The instrument must be capable of measuring solid and liquid test particles with a size resolution of 0.1 <greek-m>m or less. The accuracy of the particle size verification technique shall be 0.15 <greek-m>m or better. (4) Wind speed measurement. The wind speed in the wind tunnel shall be determined during the tests using an appropriate technique capable of a precision of 5 percent or better (e.g., hot-wire anemometry). For the wind speeds specified in Table F-2 of this subpart, the wind speed and turbulence intensity (longitudinal component and macro scale) shall be measured at a minimum of 12 test points in a cross-sectional area of the test section of the wind tunnel. The mean wind speed in the test section must be within <plus-minus>10 percent of the value specified in Table F-2 of this subpart, and the variation at any test point in the test section may not exceed 10 percent of the measured mean. (5) Aerosol rake. The cross-sectional uniformity of the particle concentration in the sampling zone of the test section shall be established during the tests using an array of isokinetic samplers, referred to as a rake. Not less than five evenly spaced isokinetic samplers shall be used to determine the particle concentration spatial uniformity in the sampling zone. The sampling zone shall be a rectangular area having a horizontal dimension not less than 1.2 times the width of the test sampler at its inlet opening and a vertical dimension not less than 25 centimeters. (6) Total aerosol isokinetic sampler. A single isokinetic sampler may be used in place of the array of isokinetic samplers for the determination of particle mass concentration used in the calculation of sampling effectiveness of the test sampler in Sec. 53.62(e)(5). In this case, the array of isokinetic samplers must be used to demonstrate particle concentration uniformity prior to the replicate measurements of sampling effectiveness.
 (7) Fluorometer. A series of calibration standards shall be prepared to encompass the minimum and maximum concentrations measured during size-selective tests. Prior to each calibration and measurement, the fluorometer shall be zeroed using an aliquot of the same solvent used for extracting aerosol mass deposits. (8) Sampler flow rate measurements. All flow rate measurements used to calculate the test atmosphere concentrations and the test results must be accurate to within <plus-minus>2 percent, referenced to a NISTtraceable primary standard. Any necessary flow rate measurement corrections shall be clearly documented. All flow rate measurements shall be performed and reported in actual volumetric units. (d) Test procedures. (1) Establish and verify wind speed. (i) Establish a wind speed specified in Table F-2 of this subpart. (ii) Measure the wind speed and turbulence intensity (longitudinal component and macro scale) at a minimum of 12 test points in a crosssectional area of the test section of the wind tunnel using a device as described in Sec. 53.62(c)(4).
 (iii) Verify that the mean wind speed in the test section of the wind tunnel during the tests is within 10 percent of the value specified in Table F-2 of this subpart. The wind speed measured at any test point in the test section shall not differ by more than 10 percent from the mean wind speed in the test section. (2) Generate aerosol. Generate particles of a size and type specified in Table F-2 of this subpart using a vibrating orifice aerosol generator. Check for the presence of satellites and adjust the generator as necessary. Calculate the physical particle size using the operating parameters of the vibrating orifice aerosol generator and record. Determine the particle's aerodynamic diameter from the calculated physical diameter and the known density of the generated particle. The calculated aerodynamic diameter must be within the tolerance specified in Table F-2 of this subpart. (3) Introduce particles into the wind tunnel. Introduce the generated particles into the wind tunnel and allow the particle concentration to stabilize.
 (4) Verify the quality of the test aerosol. (i) Extract a representative sample of the aerosol from the sampling test zone and measure the size distribution of the collected particles using an appropriate sizing technique. If the measurement instrumentation does not provide a direct measure of aerodynamic diameter, calculate the geometric mean aerodynamic diameter using the known density of the particle type in conjunction with the measured mean physical diameter. The determined mean aerodynamic diameter of the test aerosol must be within 0.15 <greek-m>m of the aerodynamic diameter calculated from the operating parameters of the vibrating orifice aerosol generator. The geometric [[Page 65831]] standard deviation of the primary particles must not exceed 1.1. (ii) Determine the population of multiplets in the collected sample. The multiplet population of the particle test atmosphere must not exceed 10 percent of the total particle population. (5) Aerosol uniformity and concentration measurement. (i) Install an array of five or more evenly spaced isokinetic samplers in the sampling zone [Sec. 53.62(c)(5)]. Collect particles on appropriate filters over a time period such that the relative error of the measured particle concentration is less than 5.0 percent. (ii) Determine the quantity of material collected with each isokinetic sampler in the array using a calibrated fluorometer. Calculate and record the mass concentration for each isokinetic sampler as: [GRAPHIC] [TIFF OMITTED] TP13DE96.085 Where i=replicate number
 j=isokinetic sampler number
 M<INF>iso=mass of material collected with the isokinetic sampler Q=isokinetic sampler volumetric flow rate t=sampling time. (iii) Calculate and record the mean mass concentration as: [GRAPHIC] [TIFF OMITTED] TP13DE96.086 Where I=replicate number
 j=isokinetic sampler number
 n=total number of isokinetic samplers. (iv) Precision calculation. (A) Calculate the coefficient of variation of the mass concentration measurements as: [GRAPHIC] [TIFF OMITTED] TP13DE96.087 Where i=replicate number
 j=isokinetic sampler number
 n=total number of isokinetic samplers. (B) If the value of CViso(I) for any replicate exceeds 10 percent, the particle concentration uniformity is unacceptable and step 5 must be repeated. If adjustment of the vibrating orifice aerosol generator or changes in the particle delivery system are necessary to achieve uniformity, steps 2 through 5 must be repeated. When an acceptable aerosol spatial uniformity is achieved, remove the array of isokinetic samplers from the wind tunnel.
 (6) Alternative measure of wind tunnel total concentration. If a single isokinetic sampler is used to determine the mean aerosol concentration in the wind tunnel, install the sampler in the wind tunnel with the sampler nozzle centered in the sampling zone [Sec. 53.62(c)(6)].
 (i) Collect particles on an appropriate filter over a time period such that the relative error of the measured concentration is less than 5.0 percent.
 (ii) Determine the quantity of material collected with the isokinetic sampler using a calibrated fluorometer. (iii) Calculate and record the mass concentration as C<INF>iso(I) as in Sec. 53.62(e)(4)(ii).
 (iv) Remove the isokinetic sampler from the wind tunnel. (7) Measure the aerosol with the candidate sampler. (i) Install the test sampler (or portion thereof) in the wind tunnel with the sampler inlet opening centered in the sampling zone. To meet the maximum blockage limit of Sec. 53.62(c)(1) or for convenience, part of the test sampler may be positioned external to the wind tunnel provided that neither the geometry of the sampler nor the length of any connecting tube or pipe is altered. Collect particles for a time period such that the relative error of the measured concentration is less than 5.0 percent.
 (ii) Remove the test sampler from the wind tunnel. (iii) Determine the quantity of material collected with the test sampler using a calibrated fluorometer. Calculate and record the mass concentration for each replicate as: [GRAPHIC] [TIFF OMITTED] TP13DE96.088 Where i=replicate number
 M<INF>cand=mass of material collected with the candidate sampler Q=candidate sampler volumetric flow rate t=sampling time. (iv) (A) Calculate and record the sampling effectiveness of the candidate sampler as:
 [GRAPHIC] [TIFF OMITTED] TP13DE96.089 Where: i = replicate number. (B) If a single isokinetic sampler is used for the determination of particle mass concentration, replace C<INF>iso(I) with C<INF>iso. (8) Obtain a minimum of three replicate measures of sampling effectiveness and calculate the mean sampling effectiveness. (i) Repeat steps in paragraphs (d) (5) through (7) of this section, as appropriate, to obtain a [[Page 65832]] minimum of three valid replicate measurements of sampling effectiveness.
 (ii) Calculate and record the average sampling effectiveness of the test sampler for the particle size and type as: [GRAPHIC] [TIFF OMITTED] TP13DE96.090 Where: i = replicate number
 n = number of replicates. (iii) Sampling effectiveness precision. (A) Calculate and record the coefficient of variation for the replicate sampling effectiveness measurements of the test sampler as: [GRAPHIC] [TIFF OMITTED] TP13DE96.091 Where: i = replicate number
 n = number of replicates. (B) If the value of CV<INF>E exceeds 10 percent, the test run (steps in paragraphs (d)(2) through (8) of this section) must be repeated until an acceptable value is obtained. (9) Repeat for each particle size and type for the selected wind speed. Repeat steps in paragraphs (d)(2) through (8) of this section until the sampling effectiveness has been measured for all particle sizes and types specified in Table F-2 of this subpart. (10) Repeat for each wind speed. Repeat steps in paragraphs (d)(1) through 9 of this section until tests have been successfully conducted for both wind speeds of 2 km/hr and 24 km/hr. (e) Calculations. (1) Graphical treatment of effectiveness data. For each wind speed given in Table F-2 of this subpart, plot the particle sampling effectiveness of the test sampler as a function of aerodynamic particle diameter (D<INF>ae) on semi-logarithmic graph paper where the aerodynamic particle diameter is the particle size established by the parameters of the VOAG in conjunction with the known particle density. Construct a best-fit, smooth curve through the data by extrapolating the sampling effectiveness curve through 100 percent at an aerodynamic particle size of 0.5 <greek-m>m and 0 percent at an aerodynamic particle size of 10 <greek-m>m. Correction for the presence of multiplets shall be performed using the techniques presented by Marple, et al (1987).
 (2) Cutpoint determination. For each wind speed determine the sampler Dp50 cutpoint defined as the aerodynamic particle size corresponding to 50 percent effectiveness from the multiplet corrected smooth curve.
 (3) Expected mass concentration calculation. For each wind speed, calculate the estimated mass concentration measurement for the test sampler under each particle size distribution (Tables F-4, F-5, and F-6 of this subpart) and compare it to the mass concentration predicted for the reference sampler, as follows:
 (i) Determine the value of corrected effectiveness using the bestfit curve at each of the particle sizes specified in the first column of Table F-4 of this subpart. Record each corrected effectiveness value as a decimal between 0 and 1 in column 2 of Table F-4 of this subpart. (ii) Calculate the interval estimated mass concentration measurement by multiplying the values of corrected effectiveness in column 2 by the interval mass concentration values in column 3 and enter the products in column 4 of Table F-4 of this subpart. (iii) Calculate the estimated mass concentration measurement by summing the values in column 4 and entering the total as the estimated mass concentration measurement for the test sampler at the bottom of column 4 of Table F-4 of this subpart.
 (iv) Calculate the estimated mass concentration ratio between the candidate method and the reference method as: [GRAPHIC] [TIFF OMITTED] TP13DE96.092 Where: C<INF>cand(est)=estimated mass concentration measurement for the test sampler, <greek-m>g/m3; and C<INF>ref(est)=estimated mass concentration measurement for the reference sampler, <greek-m>g/m3 (calculated for the reference sampler and specified at the bottom of column 7 of Table F-4 of this subpart). (v) Repeat steps in paragraphs (e) (1) through (3) of this section for Tables F-5 and F-6 of this subpart. (f) Evaluation of test results. The candidate method passes the wind tunnel effectiveness test if the Rc value for each wind speed meets the specification in Table F-1 of this subpart for each of the three particle size distributions. Sec. 53.63 Test Procedure: Wind tunnel inlet aspiration test. (a) Overview. This test applies to a candidate sampler which differs from the reference method sampler only with respect to the design of the inlet. The purpose of this test is to compare the aspiration of a Class II candidate sampler to that of the reference method sampler's inlet. This wind tunnel test uses a 3.5-micron liquid aerosol in conjunction with wind speeds of 2 km/hr and 24 km/hr. The test atmosphere concentration is alternately measured with the candidate sampler and a reference method device, both of which are operated without the 2.5-micron fractionation device installed. The test conditions are summarized in Table F-2 of this subpart (under the heading of wind tunnel inlet aspiration test). The candidate sampler must meet or exceed the acceptance criteria given in Table F-1 of this subpart.
 (b) Technical definition. Relative aspiration is the ratio (expressed as a percentage) of the aerosol mass concentration measured by the candidate sampler to that measured by a reference method sampler.
 (c) Facilities and equipment required. The facilities and equipment are identical to those required for the full wind tunnel test [Sec. 53.62(c)].
 (d) Test procedure. (1) Establish the wind tunnel test atmosphere. Follow the procedures in Sec. 53.62(e)(1) through Sec. 53.62(e)(4) to establish a test atmosphere for one of the two wind speeds specified in Table F-2 of this subpart.
 (2) Measure the aerosol concentration with the reference sampler. (i) Install the reference sampler (or portion thereof) in the wind tunnel with the sampler inlet opening centered in the sampling zone. To meet the maximum blockage limit of Sec. 53.62(c)(1) or for convenience, part of the test sampler may be positioned external to the wind tunnel provided [[Page 65833]] that neither the geometry of the sampler nor the length of any connecting tube or pipe is altered. Collect particles for a time period such that the relative error of the measured concentration [as defined in Sec. 53.61(5)] is less than 5.0 percent. (ii) Determine the quantity of material collected with the reference method sampler using a calibrated fluorometer. Calculate and record the mass concentration as: [GRAPHIC] [TIFF OMITTED] TP13DE96.093 Where: i=replicate number
 M<INF>ref=mass of material collected with the reference method sampler Q=reference method sampler volumetric flowrate t=sampling time. (iii) Remove the reference method sampler from the tunnel. (3) Measure the aerosol concentration with the candidate sampler. (i) Install the candidate sampler (or portion thereof) in the wind tunnel with the sampler inlet centered in the sampling zone. To meet the maximum blockage limit of Sec. 53.62(c)(1) or for convenience, part of the test sampler may be positioned external to the wind tunnel provided that neither the geometry of the sampler nor the length of any connecting tube or pipe is altered. Collect particles for a time period such that the relative error of the measured concentration is less than 5.0 percent.
 (ii) Determine the quantity of material collected with the candidate sampler using a calibrated fluorometer. Calculate and record the mass concentration as: [GRAPHIC] [TIFF OMITTED] TP13DE96.094 Where:
 i=replicate number
 M<INF>cand=mass of material collected with the candidate sampler Q=candidate sampler volumetric flow rate t=sampling time. (iii) Remove the candidate sampler from the wind tunnel. (4) Repeat steps in paragraphs (d) (2) and (3) of this section. Alternately measure the tunnel concentration with the reference sampler and the candidate sampler until four reference sampler and five candidate sampler measurements of the wind tunnel concentration are obtained.
 (e) Calculations. (1) Aspiration ratio. Calculate aspiration ratio for each candidate sampler run as: [GRAPHIC] [TIFF OMITTED] TP13DE96.095 where i=replicate number. (2) Precision of aspiration ratio. Calculate the precision of aspiration ratio measurements as the coefficient of variation for each aspiration ratio: [GRAPHIC] [TIFF OMITTED] TP13DE96.096 where: i=replicate number
 n=total number of measurements of aspiration ratio. (f) Evaluation of test results. The candidate method passes the inlet aspiration test if all values of A and CV<INF>A meet the acceptance criteria specified in Table F-1 of this subpart. Sec. 53.64 Test Procedure: Static fractionator test. (a) Overview. This test applies only to those candidate methods in which the sole deviation from the reference method is in the design of the 2.5-micron fractionation device. The purpose of this test is to ensure that the fractionation characteristics of the candidate fractionator are acceptably similar to that of the reference method sampler. It is recognized that various methodologies exist for quantifying fractionator effectiveness. The following commonly-employed techniques are provided for purposes of guidance. Other methodologies for determining sampler effectiveness may be used contingent upon prior approval by the Agency.
 (1) Wash-off method. Effectiveness is determined by measuring the aerosol mass deposited in the candidate sampler's afterfilter versus the aerosol mass deposited in the fractionator. The material deposited in the fractionator is recovered by washing its internal surfaces. For these wash-off tests, a fluorometer must be used to quantitate the aerosol concentration. Note that if this technique is chosen, the candidate must be reloaded with coarse aerosol prior to each test point when reevaluating the curve as specified in the loading test. (2) Static chamber method. Effectiveness is determined by measuring the aerosol mass concentration sampled by the candidate's sampler's afterfilter versus that which exists in a static chamber. A calibrated fluorometer must be used to quantify the collected aerosol deposits. The aerosol concentration is calculated as the measured aerosol mass divided by the sampled air volume.
 (3) Divided flow method. Effectiveness is determined by comparing the aerosol concentration upstream of the candidate sampler's fractionator versus that concentration which exists downstream of the candidate fractionator. These tests may utilize either fluorometry or a real-time aerosol measuring device to determine the aerosol concentration.
 (b) Technical definition. Effectiveness under static conditions is the ratio (expressed as a percentage) of the mass concentration of particles of a given size reaching the sampler filter to the mass concentration of particles of the same size approaching the sampler. (c) Facilities and equipment required. [[Page 65834]] (1) Aerosol generation. Methods for generating aerosols shall be identical to those prescribed in Sec. 53.62(c)(2). (2) Particle delivery system. Acceptable apparatus for delivering the generated aerosols to the candidate fractionator is dependent on the effectiveness measurement methodology and are defined as follows: (i) Wash-off test apparatus. The aerosol may be delivered to the candidate fractionator through direct piping (with or without an inline mixing chamber). Particle size and quality validation shall be conducted at the point where the fractionator attaches. (ii) Static chamber test apparatus. The aerosol shall be introduced into a chamber and sufficiently mixed such that the aerosol concentration within the chamber is spatially uniform. The chamber must be of sufficient size to house at least four total filter samplers, as well as the inlet of the candidate size discriminator. Particle size validation and quality validation shall be conducted on representative aerosol samples extracted from the chamber. (iii) Divided flow test apparatus. The apparatus shall allow the aerosol concentration to be measured upstream and downstream of the fractionator. The particles shall be delivered to the divided flow apparatus via a symmetrical flow path.
 (3) Particle concentration measurement. (i) Fluorometry. Fluorometers used for quantifying extracted aerosol mass deposits shall be set up, maintained, and calibrated according to the manufacturer's instructions. A series of calibration standards shall be prepared to encompass the minimum and maximum concentrations measured during size-selective tests. Prior to each calibration and measurement, the fluorometer shall be zeroed using an aliquot of the same solvent used for extracting aerosol mass deposits. (ii) Number concentration measurement. A number counting device may be used in conjunction with the divided flow test apparatus as described above. This device must have a resolution and accuracy such that primary particles may be distinguished from multiplets for all test aerosols. The measurement of number concentration shall be accomplished by integrating the primary particle peak. (d) Setup. (1) Remove the inlet from the candidate fractionator. All tests procedures shall be conducted with the inlet removed from the candidate sampler.
 (2) Surface treatment of the fractionator. Rinsing aluminum surfaces with alkaline solutions has been found to adversely affect subsequent fluorometric quantitation of aerosol mass deposits. If washoff tests are to be used for quantifying aerosol penetration, internal surfaces of the fractionator must first be plated with electroless nickel. Specifications for this plating are specified in MIL.C-26074 Grade B, Class 4 (Reference 4 in appendix A of Subpart E). (e) Test Procedure: Wash off method. (1) Clean and dry internal surfaces. Thoroughly clean and dry all internal surfaces of the candidate particle size fractionator. The internal surfaces of the fractionator shall then be prepared in strict accordance with the operating instructions specified in the samplers operating manual. Note: The procedures in this paragraph must be omitted if this test is being used to evaluate the fractionator after being loaded as specified in Sec. 53.65.
 (2) Generate aerosol. Follow the procedures for aerosol generation prescribed in Sec. 53.62(e)(2).
 (3) Verify the quality of the test aerosol. Follow the procedures for verification of test aerosol size and quality prescribed in Sec. 53.62(e)(4).
 (4) Determine effectiveness for the particle size and type being produced. (i) Collect particles downstream of the fractionator on an appropriate filter over a time period such that the relative error of the measurement is less than 5.0 percent. (ii) Determine the quantity of material collected on the afterfilter of the candidate method using a calibrated fluorometer. Calculate and record the aerosol mass concentration for the sampler filter as: [GRAPHIC] [TIFF OMITTED] TP13DE96.097 where:
 i=replicate number
 M<INF>cand=mass of material collected with the candidate sampler Q=candidate sampler volumetric flowrate t=sampling time. (iii) Wash all interior surfaces upstream of the filter and determine the quantity of material collected using a calibrated fluorometer. Calculate and record the fluorometric mass concentration of the sampler wash as: [GRAPHIC] [TIFF OMITTED] TP13DE96.098 where:
 i=replicate number
 M<INF>wash=mass of material washed from the interior surfaces of the fractionator
 Q=candidate sampler volumetric flowrate t=sampling time.
 (iv) Calculate and record the sampling effectiveness of the test sampler for this particle size as: [GRAPHIC] [TIFF OMITTED] TP13DE96.099 where i=replicate number. (v) Repeat steps in paragraphs (e)(4)(9) through (iv) of this section, as appropriate, to obtain a minimum of three replicate measurements of sampling effectiveness. (vi) Calculate and record the average sampling effectiveness of the test sampler as:
 [GRAPHIC] [TIFF OMITTED] TP13DE96.100 where:
 i=replicate number
 n=number of replicates.
 (vii) (A) Calculate and record the coefficient of variation for the replicate sampling effectiveness measurements of the test sampler as: [[Page 65835]] [GRAPHIC] [TIFF OMITTED] TP13DE96.101 where:
 i=replicate number
 n=total number of measurements.
 (B) If the value of CV<INF>E exceeds 10 percent, then steps in paragraphs (e) (2) through (4) of this section must be repeated. Note that the sampler must be loaded according to the test procedures in Sec. 53.65 prior to retesting each point if this test is being used as a post-evaluation to satisfy the requirements of Sec. 53.65. (5) Repeat steps in paragraphs (e) (1) through (4) of this section for each particle size and type specified in Table F-2 of this subpart. (f) Test procedure: Static chamber method. (1) Generate aerosol. Follow the procedures for aerosol generation prescribed in Sec. 53.62(e)(2).
 (2) Verify the quality of the test aerosol. Follow the procedures for verification of test aerosol size and quality prescribed in Sec. 53.62(e)(4).
 (3) Introduction of particles into chamber. Introduce the particles into the static chamber and allow the particle concentration to stabilize.
 (4) Install and operate the candidate sampler and at least four total filters. (i) Install the fractionator and an array of four or more equally spaced filter samplers such that the filters surround and are in the same plane as the inlet of the fractionator. (ii) Collect particles on an appropriate filter for a time period such that the relative error of the measured concentration is less than 5.0 percent.
 (5) Calculate the aerosol spatial uniformity in the chamber. (i) Determine the quantity of material collected with each total filter sampler in the array using a calibrated fluorometer. Calculate and record the mass concentration for each total filter sampler as: [GRAPHIC] [TIFF OMITTED] TP13DE96.102 where:
 i=replicate number
 j=total filter sampler number
 M<INF>total=mass of material collected with the total filter sampler Q=total filter sampler volumetric flowrate t=sample time. (ii) Calculate and record the mean mass concentration as: [GRAPHIC] [TIFF OMITTED] TP13DE96.103 where:
 n=total number of samplers
 i=replicate number
 j=filter sampler number. (iii) (A) Calculate and record the coefficient of variation of the total mass concentration as: [GRAPHIC] [TIFF OMITTED] TP13DE96.104 where:
 i=replicate number
 j=total filter sampler number
 n=number of total filter samplers. (B) If the value of CV<INF>total exceeds 10 percent, then the particle concentration uniformity is unacceptable, alterations to the static chamber test apparatus must be made, and steps in paragraphs (f) (1) through (5) of this section must be repeated. (6) Calculate the effectiveness of the candidate sampler. (i) Determine the quantity of material collected on the candidate sampler's afterfilter using a calibrated fluorometer. Calculate and record the mass concentration for the candidate sampler as: [GRAPHIC] [TIFF OMITTED] TP13DE96.105 where:
 i=replicate number
 M<INF>cand=mass of material collected with the candidate sampler Q=candidate sampler volumetric flowrate t=sample time. (ii) Calculate and record the sampling effectiveness of the candidate sampler as: [GRAPHIC] [TIFF OMITTED] TP13DE96.106 where i=replicate number. (iii) Repeat step in paragraph (f)(4) through (6) of this section, as appropriate, to obtain a minimum of three replicate measurements of sampling effectiveness.
 (iv) Calculate and record the average sampling effectiveness of the test sampler as: [GRAPHIC] [TIFF OMITTED] TP13DE96.107 where i=replicate number. (v)(A) Calculate and record the coefficient of variation for the replicate sampling effectiveness measurements of the test sampler as: [[Page 65836]] [GRAPHIC] [TIFF OMITTED] TP13DE96.108 where:
 i = replicate number
 n = number of measurements of effectiveness. (B) If the value of CV<INF>E exceeds 10 percent, then the test run (steps in paragraphs (f) (2) through (6) of this section). (7) Repeat steps in paragraphs (f) (1) through (6) of this section for each particle size and type specified in Table F-2 of this subpart. (g) Test procedure: Divided flow method.--(1) Generate calibration aerosol. Follow the procedures for aerosol generation prescribed in Sec. 53.62(e)(2).
 (2) Verify the quality of the calibration aerosol. Follow the procedures for verification of calibration aerosol size and quality prescribed in Sec. 53.62(e)(4).
 (3) Introduce the calibration aerosol into the static chamber and allow the particle concentration to stabilize. (4) Validate that transport is equal for the divided flow option. (i) With fluorometry (this applies only if fluorometry is used for detection of particles):
 (A) Install a total filter on each leg of the divided flow apparatus.
 (B) Collect particles simultaneously through both legs at 16.7 aLpm onto an appropriate filter for a time period such that the relative error of the measured concentration is less than 5.0 percent. (C) Determine the quantity of material collected on each filter using a calibrated fluorometer. Calculate and record the mass concentration measured in each leg as: [GRAPHIC] [TIFF OMITTED] TP13DE96.109 where:
 i = replicate number
 M = mass of material collected with the total filter Q = candidate sampler volumetric flowrate. (D) Repeat steps in paragraphs (g)(4)(i) (A) through (C) of this section at until a minimum of three replicate measurements are performed.
 (ii) With a number counting device such as an aerosol detector: (A) Remove all flow obstructions from the flow paths of the two legs.
 (B) Quantify the aerosol concentration of the primary particles in each leg of the apparatus.
 (C) Repeat steps in paragraphs (g)(4)(i) (A) through (B) of this section at until a minimum of three replicate measurements are performed.
 (iii) (A) Calculate the mean concentration and coefficient of variation as: [GRAPHIC] [TIFF OMITTED] TP13DE96.110 [GRAPHIC] [TIFF OMITTED] TP13DE96.111 where:
 i = replicate number
 n = number of replicates. (B) If the coefficient of variation is not less than 10 percent, then adjustments may be made in the setup, and this step must be repeated.
 (5) Determine the sampling effectiveness of the test sampler with the inlet removed by one of the following procedures. (i) With fluorometry as a detector:
 (A) Install the particle size fractionator. Install a filter downstream of one leg and a total filter on the bypass leg of the flow dividing apparatus.
 (B) Collect particles simultaneously through both legs at 16.7 aLpm onto appropriate filters for a time period such that the relative error of the measured concentration is less than 5.0 percent. (C) Determine the quantity of material collected on each filter using a calibrated fluorometer. Calculate and record the mass concentration measured by the total filter and that measured after penetrating through the candidate fractionator as follows: [GRAPHIC] [TIFF OMITTED] TP13DE96.112 [GRAPHIC] [TIFF OMITTED] TP13DE96.113 where i= replicate number.
 (ii) With a number counting device as a detector: (A) Install the particle size fractionator into one of the legs of the divided flow apparatus.
 (B) Quantify and record the aerosol number concentration of the primary particles passing through the fractionator as C<INF>cand(I). (C) Divert the flow from the leg containing the candidate fractionator to the bypass leg. Allow sufficient time for the aerosol concentration to stabilize.
 (D) Quantify and record the aerosol number concentration of the primary particles passing through the bypass leg as C<INF>total(I). (iii) Calculate and record sampling effectiveness of the candidate sampler as: [GRAPHIC] [TIFF OMITTED] TP13DE96.114 where i = replicate number. (6) Repeat step in paragraph (g)(5) of this section, as appropriate, to obtain a minimum of three replicate measurements of sampling effectiveness.
 (7) Calculate the mean and CV for replicate measurements. (i) Calculate and record the mean sampling effectiveness of the candidate sampler as: [[Page 65837]] [GRAPHIC] [TIFF OMITTED] TP13DE96.115 Where i=replicate number. (ii)(A) Calculate and record the coefficient of variation for the replicate sampling effectiveness measurements of the candidate sampler as: [GRAPHIC] [TIFF OMITTED] TP13DE96.116 Where:
 i=replicate number
 n=number of replicates. (B) If the coefficient of variation is not less than 10 percent, then the test run must be repeated (steps in paragraphs (g) (1) through (7) of this section).
 (8) Repeat steps in paragraphs (g) (1) through (7) of this section for each particle size and type specified in Table F-2 of this subpart. (h) Calculations. (1) Treatment of multiplets. For all measurements made by fluorometric analysis, data shall be corrected for the presence of multiplets as described in Sec. 53.62(f)(1). Data collected using a real-time device with sufficient resolution to discriminate primary particles from multiplets will not require multiplet correction. (2) Cutpoint determination. For each wind speed determine the sampler Dp<INF>50 cutpoint defined as the aerodynamic particle size corresponding to 50 percent effectiveness from the multiplet corrected smooth curve.
 (3) Graphical analysis and numerical integration with ambient distributions. Follow the steps outlined in Sec. 53.62(f)(3) through Sec. 53.62(f)(4) to calculate the estimated concentration measurement ratio between the candidate sampler and a reference method sampler. (i) Test evaluation. The candidate method passes the static fractionator test if the values of R<INF>c and Dp<INF>50 for each distribution meets the specifications in Table F-1 of this subpart. Sec. 53.65 Test Procedure: Loading Test (a) Overview. (1) The loading tests are designed to quantify any appreciable changes in a candidate method's performance as a function of coarse aerosol collection. This test is divided into two phases: (i) A mandatory demonstration that the candidate method is capable of single-day sampling with periodic maintenance after each 24 hours of operation; and
 (ii) An optional demonstration that the candidate is capable of multi-day sampling with the periodic maintenance schedule as defined by the manufacturer.
 (2) In the first phase, the candidate sampler is first exposed to a laboratory-generated aerosol equivalent to sampling a nominal concentration of 150 <greek-m>g/m\3\ over a 24-hour time period. Following this initial loading, the candidate sampler's effectiveness as a function of particle aerodynamic diameter must then be evaluated using by performing the test in Sec. 53.62 (full wind tunnel test). A sampler which fits the category of fractionator deviation in Sec. 53.60(e)(2) may opt to perform the test in Sec. 53.64 (static fractionator test) in lieu of the full wind tunnel test. The candidate sampler is approved for single day sampling with maintenance after each 24 hours of operation if the criteria in Table F-1 of this subpart are met for the 24-hour loading test.
 (3) In the test for extended periodic maintenance, the candidate sampler is exposed to a mass of coarse aerosol equivalent to sampling a mass concentration of 150 <greek-m>g/m\3\ over the time period that the manufacturer has specified between periodic cleaning. The candidate sampler's effectiveness as a function of particle aerodynamic diameter must then be evaluated by performing the test in Sec. 53.62 (full wind tunnel test). A sampler which fits the category of fractionator deviation in Sec. 53.60(e)(2) may opt to perform the test in Sec. 53.64 (static fractionator test) in lieu of the full wind tunnel test. If the criteria presented in Table F-1 of this subpart are met for this test, the candidate sampler is approved for multi-day sampling with the periodic maintenance schedule as specified by the manufacturer. For example, if the candidate sampler passes the reevaluation tests following loading with an aerosol mass equivalent to sampling a 150 <greek-m>g/m\3\ aerosol continuously for 7 days, then the sampler is approved for 7 day field operation before cleaning is required. (b) Technical Definitions. (1) Effectiveness after loading. Effectiveness after loading is the ratio (expressed as a percentage) of the mass concentration of particles of a given size reaching the sampler filter to the mass concentration of particles of the same size approaching the sampler.
 (2) Effectiveness after extended loading. Effectiveness after extended loading is the ratio (expressed as a percentage) of the mass concentration of particles of a given size reaching the sampler filter to the mass concentration of particles of the same size approaching the sampler.
 (c) Facilities and equipment required. (1) Particle delivery system. The particle delivery system shall consist of a static chamber or a low velocity wind tunnel having a sufficiently large crosssectional area such that the test sampler, or portion thereof, may be installed in the test section. At a minimum, the system must have a sufficiently large cross section to house the candidate sampler inlet as well as a collocated isokinetic nozzle for measuring total aerosol concentration. The mean velocity in the test section of the static chamber or wind tunnel shall not exceed 2 km/hr. (2) Aerosol generation equipment. For purposes of these tests, the test aerosol shall be produced from commercially available, bulk Arizona road dust. To provide direct interlaboratory comparability of sampler loading characteristics, the bulk dust is specified as 0-10 <greek-m>m ATD available from Powder Technology Incorporated (Burnsville, MN). To efficiently deagglomerate the bulk test dust, either a fluidized bed aerosol generator, Wright dust feeder, or sonic nozzle shall be used for the aerosol generation. Other dust generators may be used contingent upon prior approval by the Agency. (3) Isokinetic sampler. Mean aerosol concentration within the static chamber or wind tunnel shall be established using a single isokinetic sampler containing a preweighed high-efficiency total filter.
 (d) Test Procedure: 24 hour loading test. (1) Clean the candidate sampler. Internal surfaces of the candidate sampler shall be thoroughly cleaned and dried prior to performing these tests. The internal fractionator surfaces shall then be prepared in strict accordance [[Page 65838]] with the operating instructions in the sampler's operating manual referred to in Sec. 53.4(b)(3). Install the candidate sampler's inlet and the isokinetic sampler within the test chamber or wind tunnel. (2) Generate a dust cloud. Generate a dust cloud composed of Arizona test dust and introduce the dust cloud into the chamber. Allow sufficient time for the particle concentration to become steady within the chamber.
 (3) Sample aerosol with a total filter and the candidate sampler. Sample the aerosol for a sufficient time to produce an equivalent time weighted concentration (TWC) of 3600 <greek-m>g hr /m\3\. For example, this TWC level may be achieved by sampling a 150 <greek-m>g/m\3\ mean concentration for 24 hours. Alternatively, a 900 <greek-m>g/m\3\ concentration may be sampled for a 4-hour time period to produce an equivalent TWC value. Following shutdown of the system, record the sampling time and all aerosol generation parameters. (4) Determine the time-weighted concentration. (i) Weigh the isokinetic sampler's total filter on a gravimetric balance such that the relative error is less than 5.0 percent. Subtract the filter's initial mass from the final mass to determine the collected aerosol mass.
 (ii)(A) Calculate and record the TWC as: [GRAPHIC] [TIFF OMITTED] TP13DE96.117 where:
 M=collected aerosol mass, <greek-m>g Q=candidate volumetric flowrate, m\3\/hr t=sampling time, hr. (B) If the value of TWC deviates from 3600 <greek-m>g hr /m\3\ <plus-minus> 15 percent, then the loaded mass is unacceptable and steps in paragraphs (d) (1) through (3) of this section must be repeated. (5) Determine the candidate's performance after loading. The candidate sampler's effectiveness as a function of particle aerodynamic diameter must then be evaluated using by performing the test in Sec. 53.62 (full wind tunnel test). A sampler which fits the category of fractionator deviation in Sec. 53.60(e)(2) may opt to perform the test in Sec. 53.64 (static fractionator test) in lieu of the full wind tunnel test.
 (e) Test Procedure: Extended loading test. (1) Calculate the target loading mass. Calculate and record the time weighted concentration of Arizona road dust which is equivalent to exposing the sampler in an environment of 150 <greek-m>g/m\3\ over the time specified by the vendor as: [GRAPHIC] [TIFF OMITTED] TP13DE96.118 where t = the number of hours specified by the manufacturer prior to periodic cleaning. (2) Clean the candidate sampler. Internal surfaces of the candidate sampler shall be cleaned and dried prior to performing these loading tests. The internal fractionator surfaces shall then be prepared in strict accordance with the operating instructions specified in the sampler's operating manual referred to in Sec. 53.4(b)(3). Install the candidate sampler's inlet and the isokinetic sampler within the test chamber or wind tunnel.
 (3) Generate a dust cloud. Generate a dust cloud composed of Arizona test dust and introduce the dust cloud into the chamber. Allow sufficient time for the particle concentration to become steady within the chamber.
 (4) Sample aerosol with a total filter and the candidate sampler. Sample the aerosol for a time sufficient to produce an equivalent TWC equal to that of the target TWC <plus-minus>15 percent. Following shutdown of the system, record the sampling time and all aerosol generation parameters.
 (5) Determine the time weighted concentration. Weigh the isokinetic sampler's total filter on a gravimetric balance such that the relative measurement error is less than 5.0 percent. Subtract the filter's initial mass from the final mass to determine the collected aerosol mass.
 (i) (A) Calculate and record the TWC as: [GRAPHIC] [TIFF OMITTED] TP13DE96.119 (B) If the value of TWC deviates from the target TWC <plus-minus> 15 percent, then the loaded mass is unacceptable and steps in paragraphs (e) (1) through (4) of this section must be repeated. (6) Determine the candidate's effectiveness after extended loading. The candidate sampler's effectiveness as a function of particle aerodynamic diameter must then be evaluated by performing the test in Sec. 53.62 (full wind tunnel test). A sampler which fits the category of fractionator deviation in Sec. 53.60(e)(2) may opt to perform the test in Sec. 53.64 (static fractionator test) in lieu of the full wind tunnel test.
 (f) Test results. (1) 24-hour test results. If the <greek-D>C's determined in the effectiveness evaluation pass the criteria established in Table F-1 of this subpart for the 24-hour loading test, then the candidate passes this test with the stipulation that the sampling train be cleaned after each 24 hours of operation. (2) Extended test results. If the <greek-D>C's determined in the effectiveness evaluation pass the criteria established in Table F-1 of this subpart for the extended loading test, then the candidate sampler passes this test with the stipulation that the sampling train be cleaned at least of often as the frequency tested. Sec. 53.66 Test Procedure: Volatility test. (a) Overview. This test procedure is designed to ensure that the candidate sampler's volatility losses when sampling semi-volatile ambient aerosol will be comparable to that of a federal reference method sampler. The candidate sampler must meet or exceed the acceptance criteria in Table F- 1 of this subpart. (b) Technical definition. Residual mass (RM) is defined as the difference between the final filter weight following the blow-off phase and the initial filter weight preceding the loading phase. (c) Facilities and equipment required. (1) Chambers and test atmosphere. This test requires two chambers, one inside the other. The internal chamber is used to produce a well-mixed test atmosphere from which the sampling is performed. The air velocity in the chamber shall be 2.0 km/hr <plus-minus> 10 percent, perpendicular to the sampling inlet. The test section shall be sufficiently large such that the inlet, or portion installed thereof, shall block no more than 15percent of the chamber cross section in the test area. At least one reference and one candidate sampler must be tested simultaneously. Such a configuration is designated as a case. Each case needs to be repeated three times for each of the different blow-off phases (1, 2, 3, 4 hours in duration). The external chamber is used to condition, handle and weigh filters. The temperature in both chambers shall be maintained at 22 <plus-minus> 0.5 deg.C. The relative humidity (RH) in both chambers shall be maintained at 40 percent <plus-minus> 3 percent. [[Page 65839]] (2) Aerosol generation system. A pressure nebulizer shall be used to produce a polydisperse aerosol at a mass median diameter of less than 2.5 <greek-m>m. The polydisperse aerosol shall be generated from A.C.S. reagent grade glycerol of 99.5 percent minimum purity. To provide direct interlaboratory comparability of sampler volatility characteristics, the required nebulizer is Part # 5207, manufactured by Seamless, a division of Professional Medical Products, Inc (Greenwood, SC). The concentration of the aerosol inside the internal chamber shall not exceed 2 mg/m3, or any concentration that would overload the filters; (such overloading can be observed as ``wetted areas'). The concentration inside the chamber shall be at least 1 mg/m3 to obtain significant filter loading.
 (3) Air velocity verification. The chamber air velocity must be measured using an appropriate technique capable of 5 percent precision or better.
 (d) Test procedures. (1) This procedure shall be used to test the performance of candidate equivalent methods of type I and type II in which suspended particulate matter is collected on a filter. Two candidate samplers and two reference method samplers must be tested. One reference method sampler and one candidate sampler must be simultaneously subjected to the entire test procedure to ensure that both samplers are exposed to the identical aerosol. This can be achieved by using a manifold which allows connection of two samplers outside the internal chamber.
 (2) This method consists of three consecutive phases. In the first phase designated as A, temperature, relative humidity inside and outside the internal chamber must be maintained at the levels in paragraph (d)(1) of this section and the aerosol concentration and size distribution inside the internal chamber must be stabilized at the level prescribed in paragraph (d)(1) of this section. The samplers'' filters are conditioned dynamically by drawing aerosol-free air. Such air can be produced by filtering air from the external chamber through the absolute (HEPA) filter. The duration of filter conditioning shall be sufficient to obtain complete filter equilibration. In the second phase, designated as B, both samplers shall draw aerosol-laden air at a constant flow rate for 30 minutes. In the third phase designated as C, samplers draw aerosol-free and aerosol compound vapor free air, to produce partial volatilization of the collected aerosol, over single time periods of 1, 2, 3, and 4 hours. In each test, phase C is preceded by phase A and phase B using a new set of filters. Phase C shall be conducted immediately after completion of the phase B. The setup used in phase A can be used to produce air needed in phase C. (e) Filter handling. Careful handling of the filter during sampling, conditioning, and weighing is necessary to avoid errors due to damaged filters or loss of collected particles from the filters. All filters must be weighed immediately after phase A and phase C. (f) Temperature, humidity, and static charge considerations.--(1) Temperature and humidity. The effects of temperature and humidity can be minimized by equilibrating the test filters at conditions inside the external chamber. Total dynamic conditioning can be established by sequential filter weighing every 30 minutes following repetitive dynamic conditioning. The filters are considered sufficiently conditioned if the sequential weights are repeatable to <plus-minus>3<greek-m>g. The temperature and relative humidity changes in which the filter is exposed during the entire procedure must not exceed <plus-minus>+ 0.5 deg.C for the temperature and <plus-minus> 3 percent RH, respectively.
 (2) Static charge. The following procedure is suggested for minimizing charge effects. Place six or more Polonium static control devices (PSCD) inside the microbalance weighing chamber, (MWC). Two of them must be placed horizontally on the floor of the MWC and the remainder placed vertically on the back wall of the MWC. Taping two PSCD's together or using double-sided tape will help to keep them from falling. Place the filter that is to be weighed on the horizontal PSCDs facing aerosol coated surface up. Close the MWC and wait 1 minute. Open the MWC and place the filter on the balance dish. Wait 1 minute. If the charges have been neutralized the weight will stabilize within 30-60 seconds. Repeat the procedure of neutralizing charges and weighing as prescribed above several times (typically 2-4 times) until consecutive weights will differ by no more than 3 micrograms. Record the last measured weight and use this value for all subsequent calculations. (g) Artifacts. Additional negative or positive artifacts in collected mass during the first sampling period may occur. Such artifacts shall be minimized by producing and preserving the chemical composition of the air inside the internal chamber to provide thermodynamic and physicochemical states of equilibrium for the particles.
 (h) Calculations. Filters shall be weighed before the aerosol loading phase and immediately after the blow-off phase. The latter weight is subtracted from the former weight to calculate the residual mass (RM). The mass on the filter from the tested candidate sampler is multiplied by the volumetric sampling flows ratio, i.e., Frm flow rate/ Candidate flow rate, to produce a corrected residual mass (CRM). (i) Test for comparability. Comparability of the candidate method shall be established by calculating regression parameters for the regression of the CRMs obtained using candidate devices on RMs obtained using FRM devices. If the linear regression parameters [slope, intercept and correlation] meet the following values: Slope=1 <plus-minus> 0.1, intercept=0 <plus-minus> 0.15, correlation r <gr-thn-eq>0.97, the candidate method passes this test for comparability. Tables to Subpart F of Part 53 Table F-1.--Performance Specifications for PM<INF>2.5 Class II Equivalent
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 Samplers
```
 Performance test Specifications Acceptance criteria
 Full Wind Tunnel Evaluation VOAG produced Dp<INF>50 = 2.5 <greekSec. 53.62. aerosol at 2 km/hr m>m <plus-minus>
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 and 24 km/hr. 0.2 <greek-m>m; 
 Numerical Analysis 
 Results: 95% <ls- 
 thn-eq>R<INF>c<ls-thn-eq
 >105% for 
 distributions 
 presented in Tables
 F-4, F-5, and F-6. 
```
 Wind Tunnel Inlet Aspiration 3.5 <greek-m>m Relative Aspiration: Test Sec. 53.63. liquid VOAG 95% <ls-thnproduced
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 aerosol eq>Means<ls-thn-eq>
 size in conjunction 105%, CV <ls-thn- 
 with wind speeds of eq> 10%. 
 2 km/hr and 24 km/ 
 hr. 
```
 Static Fractionator Test Evaluation of the Dp<INF>50 = 2.5 <greekSec. 53.64. fractionator under m>m <plus-minus>
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 static conditions. 0.2 <greek-m>m; 
 See Table F-2 for Numerical Analysis 
 specifications Results: 95% <ls- 
 regarding particles thn-eq>R<INF>c<ls-thn-eq
 sizes and particle >105% for 
 types. distributions 
 presented in Tables
 F-4, F-5, and F-6. 
```
 [[Page 65840]]
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 
```
 Loading Test Sec. 53.65.... Loading of the clean 24 hour test and
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 candidate under Extended test; Dp<INF>50
 laboratory = 2.5 <greek-m>m 
 conditions: 24 hour <plus-minus> 0.2 
 test, extended test. <greek-m>m; 
 Numerical Analysis 
 Results: 95% <ls- 
 thn-eq>R<INF>c<ls-thn-eq
 >105% for 
 distributions 
 presented in Tables
 F-4, F-5, and F-6. 
```
 Volatility Test Sec. 53.66. Polydisperse liquid Regression
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 aerosol produced by Parameters Slope = 
 air nebulization of 1 <plus-minus> 0.1,
 A.C.S. reagent Intercept = 0 <plus-
 grade glycerol, minus> 0.15 r 
 99.5% minimum 0.97. 
 purity. 
```
 Table F-2.--Particle Sizes and Wind Speeds for Full Wind Tunnel Evaluation, Wind Tunnel Inlet Aspiration Test,
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 and Static Chamber Test
```
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 Full wind tunnel test Inlet aspiration test Static
```
 Primary partical mean size a (<greek- ------------------------------------------------ fractionator Volatility
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 m>m) 2 km/hr 24 km/hr 2 km/hr 24 km/hr test test
```
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
1.5<plus-minus>0.25................... S S S
2.0<plus-minus>0.25................... S S S
2.5<plus-minus>0.25................... S S S
2.8<plus-minus>0.25................... S S S
```
 3.5<plus-minus>0.25................... S S L L S
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
4.0<plus-minus>0.5.................... S S S
Polydisperse Glycerol Aerosol......... L
```
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
a Aerodynamic diameter. 
S=solid particles. L=liquid particles. 
```
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
Table F-3.--Critical Parameters of Idealized Ambient Particle Size Distributions
```
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
```
 Fine particle mode Coarse particle mode FRM sampler
 ------------------------------------------------------------------------------ PM<INF>2.5/ expected
 Idealized distribution Conc. Conc. PM<INF>10 mass conc. 
 MMD (<greek- Geo. std. (<greek-m>g/ MMD (<greek- Geo. std. (<greek-m>g/ ratio (<greek-m>g/
 m>m) Dev. m3) m>m) Dev. m3) m3)
```
 Coarse....................... 0.50 2 12.0 10 2 88.0 0.27 13.814 ``Typical''.................. 0.50 2 33.3 10 2 66.7 0.55 34.284 Fine......................... 0.85 2 85.0 15 2 15.0 0.94 78.539
 BILLING CODE 6560-50-P [[Page 65841]] [GRAPHIC] [TIFF OMITTED] TP13DE96.120 [[Page 65842]] [GRAPHIC] [TIFF OMITTED] TP13DE96.121 [[Page 65843]] [GRAPHIC] [TIFF OMITTED] TP13DE96.122 [[Page 65844]] Figures to Subpart F of Part 53
 [GRAPHIC] [TIFF OMITTED] TP13DE96.123 [[Page 65845]] [GRAPHIC] [TIFF OMITTED] TP13DE96.124 BILLING CODE 6560-50-C [[Page 65846]] Appendix A to Subpart F of Part 53--References
 1. Marple, V.A., K.L. Rubow, W. Turner, and J.D. Spangler, Low Flow Rate Sharp Cut Impactors for Indoor Air Sampling: Design and Calibration., JAPCA, 37: 1303-1307 (1987).
 2. Vanderpool, R.W. and K.L. Rubow, ``Generation of Large, Solid Calibration Aerosols'', J. of Aer. Sci. and Tech., 9:65-69 (1988). PART 58--[AMENDED]
 1. The authority citation for part 58 continues to read as follows: Authority: 42 U.S.C. 7410, 7601(a), 7613, and 7619. 2. Section 58.1 is amended by revising paragraph (s) and adding paragraphs (jj) through (vv) to read as follows: Sec. 58.1 Definitions.
 
 * * * *
 (s) Traceable means that a local standard has been compared and certified, either directly or via not more than one intermediate standard, to a National Institute of Standards and Technology (NIST)- certified primary standard such as a NIST-Traceable Reference Material (NTRM) or a NIST-certified Gas Manufacturer's Internal Standard (GMIS).
 * * * *
 (jj) Consolidated Metropolitan Statistical Area means the most recent area as designated by the U.S. Office of Management and Budget and population figures from the Bureau of the Census. The Department of Commerce provides ``that within metropolitan complexes of 1 million or more population, separate component areas are defined if specific criteria are met. Such areas are designated primary metropolitan statistical areas (PMSAs; and any area containing PMSAs is designated consolidated metropolitan statistical area (CMSA).'' (kk) Core PM<INF>2.5 SLAMS means SLAMS sites which are the basic component sites of the PM<INF>2.5 SLAMS regulatory network. Populationoriented core sites are intended to reflect community-wide exposure to air pollution.
 (ll) Equivalent method means a method of sampling and analyzing the ambient air for an air pollutant that has been designated as an equivalent method in accordance with this part; it does not include a method for which an equivalent method designation has been canceled in accordance with 40 CFR 53.11 or 53.16.
 (mm) Metropolitan Statistical Area (MSA) means the most recent area as designated by the U.S. Office of Management and Budget and population figures from the U.S. Bureau of the Census. The Department of Commerce defines a metropolitan area as ``one of a large population nucleus, together with adjacent communities which have a high degree of economic and social integration with that nucleus.'' (nn) Monitoring Planning Area (MPA) means a contiguous geographic area with established, well defined boundaries, such as a metropolitan statistical area, county or State, having a common area that is used for planning monitoring locations for PM<INF>2.5. MPAs may cross State boundaries, such as the Philadelphia PA-NJ MSA, and be further subdivided into spatial averaging zones. MPAs are generally oriented toward areas with populations greater than 250,000, but for convenience, those portions of a State that are not part of MSAs can be considered as a single MPA. MPAs must be defined, where applicable, in a State monitoring plan.
 (oo) Particulate Matter Monitoring Plan means a detailed plan, prepared by control agencies and submitted to EPA for approval, that describes their PM<INF>2.5 and PM<INF>10 air quality surveillance network.
 (pp) PM<INF>2.5 means particulate matter with an aerodynamic diameter less than or equal to a nominal 2.5 micrometers as measured by a reference method based on appendix L of part 50 of this chapter and designated in accordance with part 53 of this chapter or by an equivalent method designated in accordance with part 53 of this chapter.
 (qq) Population oriented monitoring or sites applies to residential areas, commercial areas, recreational areas, industrial areas where workers from more than one company are located, and other areas where a substantial number of people may spend a significant fraction of their day.
 (rr) Primary Metropolitan Statistical Area (PMSA) is a separate component of a consolidated metropolitan statistical area. For the purposes of this regulation, PMSA is used interchangeably with MSA. (ss) Reference method means a method of sampling and analyzing the ambient air for an air pollutant that is specified as a reference method in an appendix to part 50 of this chapter, or a method that has been designated as a reference method in accordance with this part; it does not include a method for which a reference method designation has been canceled in accordance with 40 CFR 53.11 or 53.16. (tt) Spatial averaging zone (SAZ) means an area with established, well defined boundaries, such as a county or census block, within a MPA that has relatively uniform concentrations of PM<INF>2.5. Monitors within a SAZ that meet certain requirements as set forth in Appendix D of this part are used to compare with the primary annual PM<INF>2.5 NAAQS using a spatial averaging procedure specified in Appendix K of 40 CFR Part 50. A SAZ may have one or more monitors. An MPA must have at least one SAZ and may have several SAZs. (uu) SPM monitors is a generic term used for all monitors other than SLAMS, NAMS, PAMS, and PSD monitors included in an agency's monitoring plan or for monitors used in special study whose data are officially reported to EPA.
 (vv) Annual State Air Monitoring Report (ASAMR) is an annual report, prepared by control agencies and submitted to EPA for approval, that consists of an annual data summary report for all pollutants and a detailed report describing any proposed changes to their air quality surveillance network.
 
 Section 58.13 is amended by revising paragraph (d) and adding new paragraphs (e) and (f) as follows:
 Sec. 58.13 Operating schedule.
 
 * * * *
 (d) For PM<INF>10 samplers--a 24-hour sample must be taken a minimum of every sixth day.
 (e) For PM<INF>2.5 samplers, everyday sampling is required for all core SLAMS, including NAMS and PAMS core stations, except during seasons or as otherwise exempted by the Regional Administrator in accordance with EPA guidance. For other SLAMS, a minimum frequency of 1 in 6 day sampling schedule is allowed and suggested. Alternative sampling frequencies are also allowed for SLAMS sites which are principally intended for comparisons to the 24-hour NAAQS. Such modifications must be approved by the EPA Administrator in accordance with EPA guidance.
 (f) Alternatives to everyday sampling. (1) PM<INF>2.5 core SLAMS sites located in monitoring planning areas (as described in section 2.8 of Appendix D of this subpart) are required to sample every day with a reference or equivalent method operating in accordance with 40 CFR part 53 and Section 2 of Appendix C to this part. However, in accordance with the monitoring priority as defined in paragraph (f)(2) of this section, established by the control agency and approved by EPA, a core SLAMS monitor may operate with a reference or equivalent method on a 1 in 3 day schedule and produce data that may be compared to the NAAQS, provided that
 [[Page 65847]] it is collocated with an acceptable continuous fine particle PM analyzer that is correlated with the reference or equivalent method. If the alternative sampling schedule is selected by the control agency and approved by EPA, the alternative schedule shall be implemented on January 1 of the year in which everyday sampling is required. The selection of correlated acceptable continuous PM analyzers and procedures for correlation with the intermittent reference or equivalent method shall be in accordance with procedures to be established and included in EPA guidance. Unless the continuous fine particle analyzer satisfies the requirements of Section 2 of Appendix C to 40 CFR Part 58, however, the data derived from the correlated acceptable continuous monitor are not eligible for direct comparisons to the NAAQS in accordance with Part 50. (2) A Metropolitan Statistical Area (or primary metropolitan statistical area) with greater than 1 million population and high concentrations of PM<INF>2.5 (greater than or equal to 80 percent of the NAAQS) shall be a Priority 1 PM monitoring area. Other monitoring planning areas may be designated as Priority 2 PM monitoring areas. (3) Core SLAMS having a correlated acceptable continuous analyzer collocated with a reference or equivalent method in a Priority 1 PM monitoring area may operate on the 1 in 3 sampling frequency only after reference or equivalent data are collected for at least two complete years and the area is determined to be attainment with the PM<INF>2.5 NAAQS in accordance with Appendix K to 40 CFR Part 50. See Figure below. After this time and for as long as the area is in attainment with the PM<INF>2.5 NAAQS, the correlated acceptable continuous option may be used in conjunction with 1 in 3 day intermittent sampling. Other core SLAMS may utilize correlated acceptable continuous monitors in conjunction with intermittent sampling on a 1 in 3 schedule for the first year of required PM<INF>2.5 sampling. (4) After one complete year of PM<INF>2.5 sampling, if a violation of the NAAQS is determined (in accordance with Appendix K to 40 CFR part 50), then everyday sampling with reference or equivalent method would be required subsequently. Otherwise, the core SLAMS in this area may continue to sample a minimum of 1 in 3 days using a reference or equivalent method together with the correlated acceptable continuous monitor. Background and transport PM<INF>2.5 core SLAMS in States with population-oriented core monitors may sample with correlated acceptable continuous alternative in accordance with the highest priority PM<INF>2.5 core SLAMS for the State. In States without populationoriented core monitors or where operation of population-oriented core monitors has been exempted by the Regional Administrator, the background and transport PM<INF>2.5 core SLAMS may also sample a minimum of 1 in 3 days. Background PM<INF>2.5 sites which are downwind of areas without anthropogenic sources of PM<INF>2.5, (e.g., the Pacific Ocean) may also sample 1 in 3 days. (5) In all monitoring situations, with a correlated acceptable continuous alternative, FRM samplers or filter-based equivalent analyzers should preferably accompany the correlated acceptable continuous monitor.
 4. Section 58.14 is revised as follows: Sec. 58.14 Special purpose monitors. (a) Except as specified in paragraph (b) of this section, any ambient air quality monitoring station other than a SLAMS or PSD station from which the State intends to use the data as part of a demonstration of attainment or nonattainment or in computing a design value for control purposes of the National Ambient Air Quality Standards (NAAQS) must meet the requirements for SLAMS as described in Sec. 58.22 and, after January 1, 1983, must also meet the requirements for SLAMS described in Sec. 58.13 and Appendices A and E of this part. (b) PM<INF>2.5 NAAQS violations shall not be made based on data produced at an SPM site during the first 3 years following the effective date of the final rule. However, a notice of NAAQS violations resulting from SPMs shall be reported to EPA in the State's annual monitoring plan and be considered by the State in the design of its overall SLAMS network, and should be considered to become permanent SLAMS during the annual network review in accordance with Sec. 58.25. (c) Any ambient air quality monitoring station other than a SLAMS or PSD station from which the State intends to use the data for SIPrelated functions other than as described in paragraph (a) of this section is not necessarily required to comply with the requirements for a SLAMS station under paragraph (a) of this section but must be operated in accordance with a monitoring schedule, methodology, quality assurance procedures, and probe or instrument-siting specifications approved by the Regional Administrator. 5. A new Sec. 58.15 is added to read as follows: Sec. 58.15 Designation of monitoring sites eligible for comparison to the PM<INF>2.5 NAAQS. (a) SLAMS and SPM monitors that will be used to make comparisons with the 24-hour and annual NAAQS for PM<INF>2.5 shall be identified in the State's monitoring plan, subject to annual review and approval by the Regional Administrator, and designated as code ``B'' in EPA's AIRS monitoring site file.
 (b) SLAMS and SPM monitors that will be used to make comparisons only with the 24-hour NAAQS for PM<INF>2.5 shall be identified in the States monitoring plan, subject to annual review and approval by the Regional Administrator, and designated as code ``D'' in EPA's AIRS monitoring site file.
 (c) All other PM<INF>2.5 sites would be designated as code ``O'' sites in EPA's AIRS monitoring site file. 6. Section 58.20 is amended by revising paragraphs (d), (e) introductory text, and (e)(5); by redesignating paragraph (f) as (g); and adding a new paragraph (f) to read as follows: Sec. 58.20 Air quality surveillance: Plan control.
 
 * * * *
 (d) Provide for the review of the air quality surveillance system on an annual basis to determine if the system meets the monitoring objectives defined in Sec. 2.8 of appendix D to this part as well as the minimum requirements for networks of SLAMS stations for PM<INF>2.5 described in Sec. 2.8.2 of appendix D of this part. Such review must identify needed modifications to the network such as termination or relocation of unnecessary stations or establishment of new stations which are necessary. For PM<INF>2.5, the review must identify needed changes to core stations, monitoring planning areas, spatial averaging zones, or monitoring sites which are eligible for comparison to the NAAQS.
 (e) Provide for having a SLAMS network description, including monitoring planning areas and spatial averaging zones for PM<INF>2.5, available for public inspection and submission to the Administrator upon request. The network description must be available at the time of plan revision submittal except for PM<INF>10 and PM<INF>2.5, which must be available by 6 months after the effective date of promulgation and must contain the following information for each SLAMS:
 * * * *
 (5) The monitoring objective, spatial scale of representativeness, and for PM<INF>2.5, the monitoring planning area, spatial averaging zone, and the site code designation to identify which site will be used to determine violations of the appropriate PM NAAQS (annual or 24-
 [[Page 65848]] hour), as defined in appendix D to this part. (f) Provide for having a list of all PM<INF>2.5 monitoring locations including SLAMS, NAMS and SPMs, which are included in the State's monitoring plan and are intended for comparison to the NAAQS, available for public inspection
 
 * * * *
 
 Section 58.23 is amended by revising the introductory text and adding a new paragraph (c) to read as follows:
 Sec. 58.23 Monitoring network completion. By January 1, 1983, with the exception of PM<INF>10 samplers which shall be within 6 months of the date of publication of the final rule and with the exception of PM<INF>2.5 samplers which shall be as described in paragraph (c) of this section.
 
 * * * *
 (c) Each PM<INF>2.5 station in the SLAMS network must be in operation in accordance with the minimum requirements of appendix D of this part, be sited in accordance with the criteria in appendix E to this part, and be located as described on the station's AIRS site identification form, according to the following schedule: (1) Within 1 year of the effective date of promulgation, the required core PM<INF>2.5 SLAMS for at least one MPA must be in operation;
 (2) Within 2 years of promulgation, all other required corepopulation oriented sites and core background and transport sites must be in operation; and
 (3) Within 3 years of promulgation, a continuous PM monitor in areas with greater than 1 million population, all NAMS sites and all additional required PM<INF>2.5 SLAMS must be in operation. 8-9. In Sec. 58.26, revise the section heading paragraph (b) introductory text and add paragraphs (d) and (e) to read as follows:
 Sec. 58.26 Annual State Air Monitoring Report.
 
 * * * *
 (b) The SLAMS annual data summary report must contain:
 * * * *
 (d) For PM--
 (1) The State shall submit a summary to the appropriate Regional Office (for SLAMS) or Administrator (through the Regional Office) (for NAMS) which details proposed changes to the PM Monitoring Plan and to be in accordance with the annual network review requirements Sec. 58.25. This shall discuss the existing PM networks, including modifications to the number, size or boundaries of monitoring planning areas and spatial averaging zones; number and location of PM SLAMS; number or location of core PM<INF>2.5 SLAMS; alternative sampling frequencies proposed for PM<INF>2.5 SLAMS (including core PM<INF>2.5 SLAMS and PM<INF>2.5 NAMS), core PM<INF>2.5 SLAMS to be designated PM<INF>2.5 NAMS; and PM SLAMS to be designated PM NAMS. (2) the State shall submit an annual summary to the appropriate Regional Office of all the ambient air quality monitoring PM data from all special purpose monitors which are described in the States monitoring plan and are intended for SIP purposes. These include those population oriented SPMs which are eligible for comparison to the PM NAAQS. The State shall certify the data in accordance with paragraph (c) of this section.
 (e) The Annual State Air Monitoring Report shall be submitted to the Regional Administrator by July 1 or by alternative annual date to be negotiated between the State and Regional Administrator. The Region shall provide review and approval/disapproval within 45 days. After the first 3 years following effective promulgation of the PM<INF>2.5 NAAQS or once a SAZ has been determined to violate the NAAQS, then changes to an MPA shall require public review and notification.
 Sec. 58.30 NAMS network establishment. 10. In Sec. 58.30, paragraph (a) introductory text is revised to read as follows:
 (a) By January 1, 1980, with the exception of PM<INF>10 samplers, which shall be by 6 months after the effective date of the final rule, and PM<INF>2.5, which shall be by 3 years after the effective date of promulgation, the State shall:
 
 * * * *
 
 In Sec. 58.31, paragraph (f) is revised to read as follows:
 Sec. 58.31 NAMS network description.
 
 * * * *
 (f) The monitoring objective, spatial scale of representativeness, and for PM<INF>2.5, the monitoring planning area, spatial averaging zone, and the site code designation to identify which site will be used to determine violations of the appropriate NAAQS (annual or 24-hour), as defined in appendix D to this part.
 
 * * * *
 
 In Sec. 58.34, the introductory text is revised to read as follows:
 Sec. 58.34 NAMS network completion. By January 1, 1981, with the exception of PM<INF>10 samplers, which shall be by 6 months after the effective date of final rule, and PM<INF>2.5, which shall be by 3 years after the effective date of final rule:
 
 * * * *
 
 In Sec. 58.35, the first sentence of paragraph (b) is revised to read as follows:
 Sec. 58.35 NAMS data submittal.
 
 * * * *
 (b) The State shall report to the Administrator all ambient air quality data for SO<INF>2, CO, O<INF>3, NO<INF>2, Pb, PM<INF>10, and PM<INF>2.5, and information specified by the AIRS Users Guide (Volume II, Air Quality Data Coding, and Volume III, Air Quality Data Storage) to be coded into the AIRS-AQS format.
 
 * * * *
 
 Revise Appendix A of part 58 to read as follows:
 Appendix A to Part 58--Quality Assurance Requirements for State and Local Air Monitoring Stations (SLAMS)
 
 General Information. 1.1 This appendix specifies the minimum quality assurance/ quality control requirements applicable to SLAMS air monitoring data submitted to EPA. State and local agencies are encouraged to develop and maintain quality assurance programs more extensive than the required minimum.
 1.2 To assure the quality of data from air monitoring measurements, two distinct and important interrelated functions must be performed. One function is the control of the measurement process through broad quality assurance activities, such as establishing policies and procedures, assigning roles and responsibilities, conducting oversight and reviews, and implementing corrective actions. The other function is the control of the measurement process through the implementation of specific quality control procedures, such as calibrations, checks, replicates, routine selfassessments, etc. In general, the greater the control of a given monitoring system, the better will be the resulting quality of the monitoring data. The results of quality assurance reviews and assessments indicate whether the control efforts are adequate or need to be improved.
 1.3 Documentation of all quality assurance and quality control efforts implemented during the data collection, analysis, and reporting phases is important to data users, who can then consider the impact of these control efforts on the data quality (see Reference 1 of this appendix). Both qualitative and quantitative assessments of the effectiveness of these control efforts should identify those areas most likely to impact the data quality and to what extent.
 1.4 Periodic assessments of SLAMS data quality are required to be reported to EPA. To provide national uniformity in this assessment and reporting of data quality for all SLAMS networks, specific assessment and reporting procedures are prescribed in detail in sections 3, 4, and 5 of this appendix. On the other hand, the selection and extent of the quality assurance and quality control [[Page 65849]] activities used by a monitoring agency depend on a number of local factors such as the field and laboratory conditions, the objectives of the monitoring, the level of the data quality needed, the expertise of assigned personnel, the cost of control procedures, pollutant concentration levels, etc. Therefore, the quality system requirements, in section 2 of this appendix, are specified in general terms to allow each State to develop a quality assurance program that is most efficient and effective for its own circumstances. 2. Quality System Requirements 2.1 Each State and local agency must develop and implement a quality assurance program consisting of policies, procedures, specifications, standards, and documentation necessary to: (1) Provide data of adequate quality to meet monitoring objectives, and
 (2) Minimize loss of air quality data due to malfunctions or out-of-control conditions. This quality assurance program must be described in detail, suitably documented, and approved by the appropriate Regional Administrator, or the Administrator's designee. The Quality Assurance Program will be reviewed during the systems audits described in section 2.5 of the appendix. 2.2 Primary guidance for developing the quality assurance program is contained in References 2-7 of this appendix, which also contain many suggested procedures, checks, and control specifications. Reference 7 of this appendix describes specific guidance for the development of a Quality Assurance Program for SLAMS. Many specific quality control checks and specifications for manual methods are included in the respective reference methods described in part 50 of this chapter or in the respective manual equivalent method descriptions available from EPA (see Reference 8 of this appendix). Similarly, quality control procedures related to specifically designated reference and equivalent method analyzers are contained in the respective operation or instruction manuals associated with those analyzers. Quality assurance guidance for meteorological systems at PAMS is contained in Reference 9. Quality assurance procedures for VOC, NOx (including NO and NO<INF>2), O<INF>3, and carbonyl measurements at PAMS must be consistent with EPA guidance. Quality assurance and control programs must follow the requirements established by ANSI E-4 (Reference 2 of this appendix) and must undergo systems audits demonstrating attainment of the requirements. This guidance, and any other pertinent information from appropriate sources, should be used by the agencies in developing their quality assurance programs. As a minimum, each quality assurance program must include operational procedures for each of the following activities:
 (1) Selection of methods, analyzers, or samplers; (2) Training;
 (3) Installation of equipment;
 (4) Selection and control of calibration standards; (5) Calibration;
 (6) Zero/span checks and adjustments of automated analyzers; (7) Control checks and their frequency; (8) Control limits for zero, span and other control checks, and respective corrective actions when such limits are surpassed; (9) Calibration and zero/span checks for multiple range analyzers (see section 2.6 of Appendix C of this part); (10) Preventive and remedial maintenance; (11) Quality control procedures for air pollution episode monitoring;
 (12) Recording and validating data; (13) Data quality assessment (precision and accuracy); (14) Documentation of quality assurance and quality control information; and
 (15) Control of pertinent documents and records in print and electronic forms.
 2.3 Pollutant Concentration and Flow Rate Standards. 2.3.1 Gaseous pollutant concentration standards (permeation devices or cylinders of compressed gas) used to obtain test concentrations for CO, SO<INF>2, NO, and NO<INF>2 must be traceable to either a National Institute of Standards and Technology (NIST) NIST-Traceable Reference Material (NTRM) or a NIST-certified Gas Manufacturer's Internal Standard (GMIS), certified in accordance with one of the procedures given in Reference 10. 2.3.2 Test concentrations for O<INF>3 must be obtained in accordance with the UV photometric calibration procedure specified in appendix D of part 50 of this chapter, or by means of a certified ozone transfer standard. Consult References 11 and 12 for guidance on primary and transfer standards for O<INF>3. 2.3.3 Flow rate measurements must be made by a flow measuring instrument that is traceable to an authoritative volume or other applicable standard. Guidance for certifying some types of flowmeters is provided in Reference 7.
 2.4 National Performance Audit Program. Agencies operating SLAMS are required to participate in EPA's National Performance Audit Program. These audits are described in sections 2.0.10 and 2.0.11 of Reference 7. For further instructions, agencies should contact either the appropriate EPA Regional Quality Assurance Coordinator or the National Performance Audit Program Coordinator, Quality Assurance Branch (MD-77B), National Exposure Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711.
 2.5 Systems Audit Programs. Systems audits of the ambient air monitoring programs of agencies operating SLAMS shall be conducted at least every three years by the appropriate EPA Regional Office. Quality assurance and control programs must follow the requirements established by ANSI E-4 (Reference 2 of this appendix) and described in Reference 7. For further instructions, agencies should contact either the appropriate EPA Regional Quality Assurance Coordinator or the Systems Audit Quality Assurance Coordinator, Office of Air Quality Planning and Standards, Emissions Monitoring and Analysis Division (MD-14), U.S. Environmental Protection Agency, Research Triangle Park, NC 27711. 3. Data Quality Assessment Requirements. 3.0.1 All ambient monitoring methods or analyzers used in SLAMS shall be tested periodically, as described in this section, to quantitatively assess the quality of the SLAMS data being routinely produced. Measurement accuracy and precision are estimated for both automated and manual methods. The individual results of these tests for each method or analyzer shall be reported to EPA as specified in section 4. EPA will then calculate quarterly integrated estimates of precision and accuracy applicable to the SLAMS data as described in section 5 of this appendix. Data assessment results should be reported to EPA only for methods and analyzers approved for use in SLAMS monitoring under appendix C of this part. 3.0.2 The integrated estimates of the data quality will be calculated on the basis of ``reporting organizations'' and may also be calculated for each region and for the entire nation. These estimates will primarily pool all methods for each pollutant, but estimates may also be made for specific instrument types identified by EPA method code, which is uniquely related to each reference and equivalent method designated by the EPA under part 53 of this chapter. A ``reporting organization'' is defined as a State, subordinate organization within a State, or other organization that is responsible for a set of stations that monitors the same pollutant and for which precision or accuracy assessments can be pooled. States must define one or more reporting organizations for each pollutant such that each monitoring station in the State SLAMS network is included in one, and only one, reporting organization. 3.0.3 Each reporting organization shall be defined such that precision or accuracy among all stations in the organization can be expected to be reasonably homogeneous, as a result of common factors. Common factors that should be considered by States in defining reporting organizations include: (1) Operation by a common team of field operators; (2) Common calibration facilities; and (3) Support by a common laboratory or headquarters. Where there is uncertainty in defining the reporting organizations or in assigning specific sites to reporting organizations, States shall consult with the appropriate EPA Regional Office for guidance. All definitions of reporting organizations shall be subject to final approval by the appropriate EPA Regional Office. 3.0.4 Assessment results shall be reported as specified in section 4 of this Appendix. Concentration and flow rate standards must be as specified in sections 2.3 or 3.4 of this Appendix. In addition, working standards and equipment used for accuracy audits must not be the same standards and equipment used for routine calibrations. Additional information and guidance in the technical aspects of conducting these tests may be found in Reference 7 or in the operation or instruction manual associated with the analyzer or sampler. Concentration measurements reported from analyzers or analytical systems (indicated concentrations) should be based on stable readings and must [[Page 65850]] be derived by means of the same calibration curve and data processing system used to obtain the routine air monitoring data (see Reference 1 and Reference 7 of this Appendix). Table A-1 of this Appendix provides a summary of the minimum data quality assessment requirements, which are described in more detail in the following sections.
 3.1 Precision of Automated Methods. 3.1.1 Methods for SO<INF>2, NO<INF>2, O<INF>3 and CO. A onepoint precision check must be performed at least once every two weeks on each automated analyzer used to measure SO<INF>2, NO<INF>2, O<INF>3 and CO. The precision check is made by challenging the analyzer with a precision check gas of known concentration (effective concentration for open path analyzers) between 0.08 and 0.10 ppm for SO<INF>2, NO<INF>2, and O<INF>3 analyzers, and between 8 and 10 ppm for CO analyzers. To check the precision of SLAMS analyzers operating on ranges higher than 0 to 1.0 ppm SO<INF>2, NO<INF>2, and O<INF>3, or 0 to 100 ppm for CO, use precision check gases of appropriately higher concentration as approved by the appropriate Regional Administrator or the Regional Administrator's designee. However, the results of precision checks at concentration levels other than those specified above need not be reported to EPA. The standards from which precision check test concentrations are obtained must meet the specifications of section 2.3 of this Appendix.
 3.1.1.1 Except for certain CO analyzers described below, point analyzers must operate in their normal sampling mode during the precision check, and the test atmosphere must pass through all filters, scrubbers, conditioners and other components used during normal ambient sampling and as much of the ambient air inlet system as is practicable. If permitted by the associated operation or instruction manual, a CO point analyzer may be temporarily modified during the precision check to reduce vent or purge flows, or the test atmosphere may enter the analyzer at a point other than the normal sample inlet, provided that the analyzer's response is not likely to be altered by these deviations from the normal operational mode. If a precision check is made in conjunction with a zero or span adjustment, it must be made prior to such zero or span adjustments. Randomization of the precision check with respect to time of day, day of week, and routine service and adjustments is encouraged where possible.
 3.1.1.2 Open path analyzers are tested by inserting a test cell containing a precision check gas concentration into the optical measurement beam of the instrument. If possible, the normally used transmitter, receiver, and as appropriate, reflecting devices should be used during the test, and the normal monitoring configuration of the instrument should be altered as little as possible to accommodate the test cell for the test. However, if permitted by the associated operation or instruction manual, an alternate local light source or an alternate optical path that does not include the normal atmospheric monitoring path may be used. The actual concentration of the precision check gas in the test cell must be selected to produce an ``effective concentration'' in the range specified above. Generally, the precision test concentration measurement will be the sum of the atmospheric pollutant concentration and the precision test concentration. If so, the result must be corrected to remove the atmospheric concentration contribution. The ``corrected concentration'' is obtained by subtracting the average of the atmospheric concentrations measured by the open path instrument under test immediately before and immediately after the precision check test from the precision test concentration measurement. If the difference between these before and after measurements is greater than 20 percent of the effective concentration of the test gas, discard the test result and repeat the test. If possible, open path analyzers should be tested during periods when the atmospheric pollutant concentrations are relatively low and steady. 3.1.1.3 Report the actual concentration (effective concentration for open path analyzers) of the precision check gas and the corresponding concentration measurement (corrected concentration, if applicable, for open path analyzers) indicated by the analyzer. The percent differences between these concentrations are used to assess the precision of the monitoring data as described in section 5.1.
 3.1.2 Methods for particulate matter. A one-point precision check must be performed at least once every two weeks on each automated analyzer used to measure PM<INF>10 and PM<INF>2.5. The precision check is made by checking the operational flow rate of the analyzer. If a precision flow rate check is made in conjunction with a flow rate adjustment, it must be made prior to such flow rate adjustment. Randomization of the precision check with respect to time of day, day of week, and routine service and adjustments is encouraged where possible.
 3.1.2.1 Standard procedure: Use a flow rate transfer standard certified in accordance with section 2.3.3 to check the analyzer's normal flow rate. Care should be used in selecting and using the flow rate measurement device such that it does not alter the normal operating flow rate of the analyzer. Report the actual analyzer flow rate measured by the transfer standard and the corresponding flow rate measured, indicated, or assumed by the analyzer. 3.1.2.2 Alternative procedure:
 3.1.2.2.1 It is permissible to obtain the precision check flow rate data from the analyzer's internal flow meter without the use of an external flow rate transfer standard, provided that-- 3.1.2.2.1.1 the flow meter is audited with an external flow rate transfer standard at least every 6 months; 3.1.2.2.1.2 records of at least the 3 most recent flow audits of the instrument's internal flow meter over at least several weeks confirm that the flow meter is stable, verifiable and accurate to <plus-minus>4%; and
 3.1.2.2.1.3 the instrument and flow meter give no indication of improper operation.
 3.1.2.2.2 With suitable communication capability, the precision check may thus be carried out remotely. For this procedure, report the set-point flow rate as the ``actual flow rate'' along with the flow rate measured or indicated by the analyzer flow meter. 3.1.2.2.3 For either procedure, the percent differences between the actual and indicted flow rates are used to assess the precision of the monitoring data as described in section 5.1 of this Appendix A (using flow rates in lieu of concentrations). The percent differences between these concentrations are used to assess the precision of the monitoring data as described in section 5.1. 3.2 Accuracy of Automated Methods. 3.2.1 Methods for SO<INF>2, NO<INF>2, O<INF>3, or CO. 3.2.1.1 Each calendar quarter (during which analyzers are operated), audit at least 25 percent of the SLAMS analyzers that monitor for SO<INF>2, NO<INF>2, O<INF>3, or CO such that each analyzer is audited at least once per year. If there are fewer than four analyzers for a pollutant within a reporting organization, randomly reaudit one or more analyzers so that at least one analyzer for that pollutant is audited each calendar quarter. Where possible, EPA strongly encourages more frequent auditing, up to an audit frequency of once per quarter for each SLAMS analyzer. 3.2.1.2 The audit is made by challenging the analyzer with at least one audit gas of known concentration (effective concentration for open path analyzers) from each of the following ranges applicable to the analyzer being audited:
 
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
 
 Concentration range, ppm
 Audit level -----------------------------------
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
 
 SO<INF>2, O<INF>3 NO<INF>2 CO
 
 1................................... 0.03-0.08 0.03-0.08 3-8 2................................... 0.15-0.20 0.15-0.20 15-20 3................................... 0.35-0.45 0.35-0.45 35-45
 4....................... 0.80-0.90 ...... 80-90
 [[Page 65851]] NO<INF>2 audit gas for chemiluminescence-type NO<INF>2 analyzers must also contain at least 0.08 ppm NO. 3.2.1.3 NO concentrations substantially higher than 0.08 ppm, as may occur when using some gas phase titration (GPT) techniques, may lead to audit errors in chemiluminescence analyzers due to inevitable minor NO-NO<INF>X channel imbalance. Such errors may be atypical of routine monitoring errors to the extent that such NO concentrations exceed typical ambient NO concentrations at the site. These errors may be minimized by modifying the GPT technique to lower the NO concentrations remaining in the NO<INF>2 audit gas to levels closer to typical ambient NO concentrations at the site. 3.2.1.4 To audit SLAMS analyzers operating on ranges higher than 0 to 1.0 ppm for SO<INF>2, NO<INF>2, and O<INF>3 or 0 to 100 ppm for CO, use audit gases of appropriately higher concentration as approved by the appropriate Regional Administrator or the Administrators's designee. The results of audits at concentration levels other than those shown in the above table need not be reported to EPA.
 3.2.1.5 The standards from which audit gas test concentrations are obtained must meet the specifications of section 2.3. The gas standards and equipment used for auditing must not be the same as the standards and equipment used for calibration or calibration span adjustments. The auditor should not be the operator or analyst who conducts the routine monitoring, calibration, and analysis. 3.2.1.6 For point analyzers, the audit shall be carried out by allowing the analyzer to analyze the audit test atmosphere in its normal sampling mode such that the test atmosphere passes through all filters, scrubbers, conditioners, and other sample inlet components used during normal ambient sampling and as much of the ambient air inlet system as is practicable. The exception provided in section 3.1 for certain CO analyzers does not apply for audits. 3.2.1.7 Open path analyzers are audited by inserting a test cell containing the various audit gas concentrations into the optical measurement beam of the instrument. If possible, the normally used transmitter, receiver, and, as appropriate, reflecting devices should be used during the audit, and the normal monitoring configuration of the instrument should be modified as little as possible to accommodate the test cell for the audit. However, if permitted by the associated operation or instruction manual, an alternate local light source or an alternate optical path that does not include the normal atmospheric monitoring path may be used. The actual concentrations of the audit gas in the test cell must be selected to produce ``effective concentrations'' in the ranges specified in this section 3.2. Generally, each audit concentration measurement result will be the sum of the atmospheric pollutant concentration and the audit test concentration. If so, the result must be corrected to remove the atmospheric concentration contribution. The ``corrected concentration'' is obtained by subtracting the average of the atmospheric concentrations measured by the open path instrument under test immediately before and immediately after the audit test (or preferably before and after each audit concentration level) from the audit concentration measurement. If the difference between the before and after measurements is greater than 20 percent of the effective concentration of the test gas standard, discard the test result for that concentration level and repeat the test for that level. If possible, open path analyzers should be audited during periods when the atmospheric pollutant concentrations are relatively low and steady. Also, the monitoring path length must be reverified to within <plus-minus>3 percent to validate the audit, since the monitoring path length is critical to the determination of the effective concentration.
 3.2.1.8 Report both the actual concentrations (effective concentrations for open path analyzers) of the audit gases and the corresponding concentration measurements (corrected concentrations, if applicable, for open path analyzers) indicated or produced by the analyzer being tested. The percent differences between these concentrations are used to assess the accuracy of the monitoring data as described in section 5.2.
 3.2.2 Methods for particulate matter. 3.2.2.1 Each calendar quarter, audit the flow rate of each SLAMS PM<INF>2.5 analyzer and at least 25 percent of the SLAMS PM<INF>10 analyzers such that each PM<INF>10 analyzer is audited at least once per year. If there are fewer than four PM10 analyzers within a reporting organization, randomly re-audit one or more analyzers so that at least one analyzer is audited each calendar quarter. Where possible, EPA strongly encourages more frequent auditing, up to an audit frequency of once per quarter for each SLAMS analyzer.
 3.2.2.2 The audit is made by measuring the analyzer's normal operating flow rate, using a flow rate transfer standard certified in accordance with section 2.3.3. The flow rate standard used for auditing must not be the same flow rate standard used to calibrate the analyzer. However, both the calibration standard and the audit standard may be referenced to the same primary flow rate or volume standard. Great care must be used in auditing the flow rate to be certain that the flow measurement device does not alter the normal operating flow rate of the analyzer. Report the audit (actual) flow rate and the corresponding flow rate indicated or assumed by the sampler. The percent differences between these flow rates are used to calculate accuracy as described in section 5.4.1. 3.3 Precision of Manual Methods.
 3.3.1 For each network of manual methods other than for PM<INF>2.5, select one or more monitoring sites within the reporting organization for duplicate, collocated sampling as follows: for 1 to 5 sites, select 1 site; for 6 to 20 sites, select 2 sites; and for over 20 sites, select 3 sites. For each network of manual methods for PM<INF>2.5, select one or more monitoring sites within the reporting organization for duplicate, collocated sampling as follows: for 1 to 10 sites, select 1 site; for 11 to 20 sites, select 2 sites; and for over 20 sites, select 3 sites. Where possible, additional collocated sampling is encouraged. For purposes of precision assessment, networks for measuring TSP, PM<INF>10, and PM<INF>2.5 shall be considered separately from one another. Sites having annual mean particulate matter concentrations among the highest 25 percent of the annual mean concentrations for all the sites in the network must be selected or, if such sites are impractical, alternative sites approved by the Regional Administrator may be selected.
 3.3.2 In determining the number of collocated sites required for PM<INF>10, monitoring networks for lead should be treated independently from networks for particulate matter, even though the separate networks may share one or more common samplers. However, a single pair of samplers collocated at a common-sampler monitoring site that meets the requirements for both a collocated lead site and a collocated particulate matter site may serve as a collocated site for both networks.
 3.3.3 In determining the number of collocated sites required for PM<INF>2.5, monitoring networks for visibility should not be treated independently from networks for particulate matter, as the separate networks may share one or more common samplers. However, for class I visibility areas, EPA will accept visibility aerosol mass measurement in lieu of a PM<INF>2.5 measurement if the latter measurement is unavailable.
 3.3.4 The two collocated samplers must be within 4 meters of each other, and particulate matter samplers must be at least 2 meters apart to preclude airflow interference. Calibration, sampling, and analysis must be the same for both collocated samplers and the same as for all other samplers in the network. 3.3.5 For each pair of collocated samplers, designate one sampler as the primary sampler whose samples will be used to report air quality for the site, and designate the other as the duplicate sampler. The paired samplers must each have the same designation number. Each duplicate sampler must be operated concurrently with its associated routine sampler at least once per week. The operation schedule should be selected so that the sampling days are distributed evenly over the year and over the seven days of the week. The every-6-day schedule used by many monitoring agencies is recommended. Report the measurements from both samplers at each collocated sampling site, including measurements falling below the limits specified in 5.3.1. The percent differences in measured concentration (<greek-m>g/m\3\) between the two collocated samplers are used to calculate precision as described in section 5.3. 3.4 Accuracy of Manual Methods. The accuracy of manual sampling methods is assessed by auditing a portion of the measurement process. For particulate matter methods, the flow rate during sample collection is audited. For SO<INF>2 and NO<INF>2 methods, the analytical measurement is audited. For Pb methods, the flow rate and analytical measurement are audited.
 3.4.1 Methods for PM<INF>2.5 and PM<INF>10. 3.4.1.1 Each calendar quarter, audit the flow rate of each PM<INF>2.5 sampler and audit at least 25 percent of the PM<INF>10 samplers such [[Page 65852]] that each PM<INF>10 sampler is audited at least once per year. If there are fewer than four PM<INF>10 samplers within a reporting organization, randomly reaudit one or more samplers so that one sampler is audited each calendar quarter. Audit each sampler at its normal operating flow rate, using a flow rate transfer standard certified in accordance with section 2.3.3. The flow rate standard used for auditing must not be the same flow rate standard used to calibrate the sampler. However, both the calibration standard and the audit standard may be referenced to the same primary flow rate standard. The flow audit should be scheduled so as to avoid interference with a scheduled sampling period. Report the audit (actual) flow rate and the corresponding flow rate indicated by the sampler's normally used flow indicator. The percent differences between these flow rates are used to calculate accuracy as described in section 5.4.1.
 3.4.1.2 Great care must be used in auditing high-volume particulate matter samplers having flow regulators because the introduction of resistance plates in the audit flow standard device can cause abnormal flow patterns at the point of flow sensing. For this reason, the flow audit standard should be used with a normal filter in place and without resistance plates in auditing flowregulated high-volume samplers, or other steps should be taken to assure that flow patterns are not perturbed at the point of flow sensing.
 3.4.2 SO<INF>2 Methods.
 3.4.2.1 Prepare audit solutions from a working sulfitetetrachloromercurate (TCM) solution as described in section 10.2 of the SO<INF>2 Reference Method (appendix A of part 50 of this chapter). These audit samples must be prepared independently from the standardized sulfite solutions used in the routine calibration procedure. Sulfite-TCM audit samples must be stored between 0 and 5 deg.C and expire 30 days after preparation. 3.4.2.2 Prepare audit samples in each of the concentration ranges of 0.2-0.3, 0.5-0.6, and 0.8-0.9 <greek-m>g SO<INF>2/ml. Analyze an audit sample in each of the three ranges at least once each day that samples are analyzed and at least twice per calendar quarter. Report the audit concentrations (in <greek-m>g SO<INF>2/ml) and the corresponding indicated concentrations (in <greek-m>g SO<INF>2/ml). The percent differences between these concentrations are used to calculate accuracy as described in section 5.4.2. 3.4.3 NO<INF>2 Methods. Prepare audit solutions from a working sodium nitrite solution as described in the appropriate equivalent method (see Reference 8). These audit samples must be prepared independently from the standardized nitrite solutions used in the routine calibration procedure. Sodium nitrite audit samples expire in 3 months after preparation. Prepare audit samples in each of the concentration ranges of 0.2-0.3, 0.5-0.6, and 0.8-0.9 <greek-m>g NO<INF>2/ml. Analyze an audit sample in each of the three ranges at least once each day that samples are analyzed and at least twice per calendar quarter. Report the audit concentrations (in <greek-m>g NO<INF>2/ml) and the corresponding indicated concentrations (in <greek-m>g NO<INF>2/ml). The percent differences between these concentrations are used to calculate accuracy as described in section 5.4.2.
 3.4.4 Pb Methods.
 3.4.4.1 For the Pb Reference Method (appendix G of part 50 of this chapter), the flow rates of the high-volume Pb samplers shall be audited as part of the TSP network using the same procedures described in Section 3.4.1. For agencies operating both TSP and Pb networks, 25 percent of the total number of high-volume samplers are to be audited each quarter.
 3.4.4.2 Each calendar quarter, audit the Pb Reference Method analytical procedure using glass fiber filter strips containing a known quantity of Pb. These audit sample strips are prepared by depositing a Pb solution on unexposed glass fiber filter strips of dimensions 1.9 cm by 20.3 cm (\3/4\ inch by 8 inch) and allowing them to dry thoroughly. The audit samples must be prepared using batches of reagents different from those used to calibrate the Pb analytical equipment being audited. Prepare audit samples in the following concentration ranges:
 
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
 
 Equivalent Pb ambient Pb
 Range concentration, concentration,
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
 
 <greek-m>g/strip <greek-m>g/m3
 ---------------------------------------------------------------\1\------ 1................................... 100-300 0.5-1.5 2................................... 600-1000 3.0-5.0
 \1\ Equivalent ambient Pb concentration in <greek-m>g/m3 is based on sampling at 1.7 m3/min for 24 hours on a 20.3 cm x 25.4 cm (8 inch x
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
 
 10 inch) glass fiber filter.
 3.4.4.3 Audit samples must be extracted using the same extraction procedure used for exposed filters. 3.4.4.4 Analyze three audit samples in each of the two ranges each quarter samples are analyzed. The audit sample analyses shall be distributed as much as possible over the entire calendar quarter. Report the audit concentrations (in <greek-m>g Pb/strip) and the corresponding measured concentrations (in <greek-m>g Pb/strip) using unit code 77. The percent differences between the concentrations are used to calculate analytical accuracy as described in section 5.4.2. 3.4.4.5 The accuracy of an equivalent Pb method is assessed in the same manner as for the reference method. The flow auditing device and Pb analysis audit samples must be compatible with the specific requirements of the equivalent method. 4. Reporting Requirements For each pollutant, prepare a list of all monitoring sites and their AIRS site identification codes in each reporting organization and submit the list to the appropriate EPA Regional Office, with a copy to AIRS-AQS. Whenever there is a change in this list of monitoring sites in a reporting organization, report this change to the Regional Office and to AIRS-AQS.
 4.1 Quarterly Reports. For each quarter, each reporting organization shall report to AIRS-AQS directly (or via the appropriate EPA Regional Office for organizations not direct users of AIRS) the results of all valid precision and accuracy tests it has carried out during the quarter. The quarterly reports of precision and accuracy data must be submitted consistent with the data reporting requirements specified for air quality data as set forth in Sec. 58.35(c). Each organization shall report all collocated measurements including those falling below the levels specified in section 5.3.1. Report results from invalid tests, from tests carried out during a time period for which ambient data immediately prior or subsequent to the tests were invalidated for appropriate reasons, and from tests of methods or analyzers not approved for use in SLAMS monitoring networks under Appendix C of this part. Such data should be flagged so that it will not be utilized for quantitative assessment of precision and accuracy. 4.2 Annual Reports.
 4.2.1 When precision and accuracy estimates for a reporting organization have been calculated for all four quarters of the calendar year, EPA will calculate the properly weighted probability limits for precision and accuracy for the entire calendar year. These limits will then be associated with the data submitted in the annual SLAMS report required by Sec. 58.26. 4.2.2 Each reporting organization shall submit, along with its annual SLAMS report, a listing by pollutant of all monitoring sites in the reporting organization. 5. Calculations for Data Quality Assessment Calculation of estimates of integrated precision and accuracy are carried out by EPA according to the following procedures. Reporting organizations should report the results of individual precision and accuracy tests as specified in sections 3 and 4 of this appendix even though they may elect to perform some or all of the calculations in this section on their own. 5.1 Precision of Automated Methods. Estimates of the precision of automated methods are calculated from the results of biweekly precision checks as specified in section 3.1. At the end of each calendar quarter, an integrated precision probability interval for all SLAMS analyzers in the organization is calculated for each pollutant.
 5.1.1 Single Analyzer Precision.
 5.1.1.1 The percent difference (d<INF>i) for each precision check is calculated using equation 1, where Y<INF>i is the concentration indicated by the analyzer for the I-th precision check and X<INF>i is the known concentration for the I-th precision check. [GRAPHIC] [TIFF OMITTED] TP13DE96.125 5.1.1.2 For each analyzer, the quarterly average (d<INF>j) is calculated with equation 2, and the standard deviation (S<INF>j) with equation 3, where n is the number of precision checks on the instrument made during the calendar quarter. For example, n should be 6 or 7 if precision checks are made biweekly during a quarter. [GRAPHIC] [TIFF OMITTED] TP13DE96.126 [[Page 65853]] [GRAPHIC] [TIFF OMITTED] TP13DE96.127 5.1.2 Precision for Reporting Organization. 5.1.2.1 For each pollutant, the average of averages (D) and the pooled standard deviation (S<INF>a) are calculated for all analyzers audited for the pollutant during the quarter, using either equations 4 and 5 or 4a and 5a, where k is the number of analyzers audited within the reporting organization for a single pollutant. [GRAPHIC] [TIFF OMITTED] TP13DE96.128 [GRAPHIC] [TIFF OMITTED] TP13DE96.129 [GRAPHIC] [TIFF OMITTED] TP13DE96.130 [GRAPHIC] [TIFF OMITTED] TP13DE96.131 5.1.2.2 Equations 4 and 5 are used when the same number of precision checks are made for each analyzer. Equations 4a and 5a are used to obtain a weighted average and a weighted standard deviation when different numbers of precision checks are made for the analyzers.
 5.1.2.3 For each pollutant, the 95 Percent Probability Limits for the precision of a reporting organization are calculated using equations 6 and 7. Upper 95 Percent Probability Limit=D+1.96 S<INF>a (6) Lower 95 Percent Probability Limit=D-1.96 S<INF>a (7)
 5.2 Accuracy of Automated Methods. Estimates of the accuracy of automated methods are calculated from the results of independent audits as described in section 3.2. At the end of each calendar quarter, an integrated accuracy probability interval for all SLAMS analyzers audited in the reporting organization is calculated for each pollutant. Separate probability limits are calculated for each audit concentration level in section 3.2. 5.2.1 Single Analyzer Accuracy. The percentage difference (d<INF>i) for each audit concentration is calculated using equation 1, where Y<INF>i is the analyzer's indicated concentration measurement from the I-th audit check and X<INF>i is the actual concentration of the audit gas used for the I-th audit check. 5.2.2 Accuracy for Reporting Organization. 5.2.2.1 For each audit concentration level of a particular pollutant, the average (D) of the individual percentage differences (d<INF>i) for all n analyzers audited during the quarter is calculated using equation 8.
 [GRAPHIC] [TIFF OMITTED] TP13DE96.132 5.2.2.2 For each concentration level of a particular pollutant, the standard deviation (S<INF>a) of all the individual percentage differences for all n analyzers audited during the quarter is calculated, using equation 9.
 [GRAPHIC] [TIFF OMITTED] TP13DE96.133 5.2.2.3 For reporting organizations having four or fewer analyzers for a particular pollutant, only one audit is required each quarter. For such reporting organizations, the audit results of two consecutive quarters are required to calculate an average and a standard deviation, using equations 8 and 9. Therefore, the reporting of probability limits shall be on a semiannual (instead of a quarterly) basis.
 5.2.2.4 For each pollutant, the 95 Percent Probability Limits for the accuracy of a reporting organization are calculated at each audit concentration level using equations 6 and 7. 5.3 Precision of Manual Methods. Estimates of precision of manual methods are calculated from the results obtained from collocated samplers as described in section 3.3. At the end of each calendar quarter, an integrated precision probability interval for all collocated samplers operating in the reporting organization is calculated for each manual method network. 5.3.1 Single Sampler Precision.
 5.3.1.1 At low concentrations, agreement between the measurements of collocated samplers, expressed as percent differences, may be relatively poor. For this reason, collocated measurement pairs are selected for use in the precision calculations only when both measurements are above the following limits: TSP: 20 <greek-m>g/m3; SO<INF>2: 45 <greek-m>g/m3; NO<INF>2: 30 <greek-m>g/m3; Pb: 0.15 <greek-m>g/m3; PM<INF>10: 20 <greek-m>g/m3; and PM<INF>2.5: 6 <greek-m>g/m3. 5.3.1.2 For each selected measurement pair, the percent difference (d<INF>i) is calculated, using equation 10, [[Page 65854]] [GRAPHIC] [TIFF OMITTED] TP13DE96.134 where Y<INF>i is the pollutant concentration measurement obtained from the duplicate sampler and X<INF>i is the concentration measurement obtained from the primary sampler designated for reporting air quality for the site. For each site, the quarterly average percent difference (d<INF>j) is calculated from equation 2 and the standard deviation (S<INF>j) is calculated from equation 3, where n=the number of selected measurement pairs at the site. 5.3.2 Precision for Reporting Organization. 5.3.2.1 For each pollutant, the average percentage difference (D) and the pooled standard deviation (S<INF>a) are calculated, using equations 4 and 5, or using equations 4a and 5a if different numbers of paired measurements are obtained at the collocated sites. For these calculations, the k of equations 4, 4a, 5 and 5a is the number of collocated sites.
 5.3.2.2 The 95 Percent Probability Limits for the integrated precision for a reporting organization are calculated using equations 11 and 12. Upper 95 Percent Probability
 [GRAPHIC] [TIFF OMITTED] TP13DE96.135 Lower 95 Percent Probability Limit=D <plus-minus> 1.96 S<INF>a/<radical>2 (12) 5.4 Accuracy of Manual Methods. Estimates of the accuracy of manual methods are calculated from the results of independent audits as described in section 3.4. At the end of each calendar quarter, an integrated accuracy probability interval is calculated for each manual method network operated by the reporting organization. 5.4.1 Particulate Matter Samplers other than PM<INF>2.5 (including reference method Pb samplers). 5.4.1.1 Single Sampler Accuracy. For the flow rate audit described in Section 3.4.1, the percentage difference (d<INF>i) for each audit is calculated using equation 1, where X<INF>i represents the known flow rate and Y<INF>i represents the flow rate indicated by the sampler.
 5.4.1.2 Accuracy for Reporting Organization. For each type of particulate matter measured (e.g., TSP/Pb), the average (D) of the individual percent differences for all similar particulate matter samplers audited during the calendar quarter is calculated using equation 8. The standard deviation (S<INF>a) of the percentage differences for all of the similar particulate matter samplers audited during the calendar quarter is calculated using equation 9. The 95 percent probability limits for the integrated accuracy for the reporting organization are calculated using equations 6 and 7. For reporting organizations having four or fewer particulate matter samplers of one type, only one audit is required each quarter, and the audit results of two consecutive quarters are required to calculate an average and a standard deviation. In that case, probability limits shall be reported semi-annually rather than quarterly.
 5.4.2 Analytical Methods for SO<INF>2, NO<INF>2, and Pb. 5.4.2.1 Single Analysis-Day Accuracy. For each of the audits of the analytical methods for SO<INF>2, NO<INF>2, and Pb described in sections 3.4.2, 3.4.3, and 3.4.4, the percentage difference (d<INF>j) at each concentration level is calculated using equation 1, where X<INF>j represents the known value of the audit sample and Y<INF>j represents the value of SO<INF>2, NO<INF>2, or Pb indicated by the analytical method.
 5.4.2.1 Accuracy for Reporting Organization. For each analytical method, the average (D) of the individual percent differences at each concentration level for all audits during the calendar quarter is calculated using equation 8. The standard deviation (S<INF>a) of the percentage differences at each concentration level for all audits during the calendar quarter is calculated using equation 9. The 95 percent probability limits for the accuracy for the reporting organization are calculated using equations 6 and 7. 6.0 Annual Operational Evaluation of PM<INF>2.5 Methods. All PM<INF>2.5 monitoring methods or analyzers used in SLAMS shall be evaluated annually, as described in this section, to quantitatively assess the quality of the SLAMS data being routinely produced. This evaluation is derived from the results of collocated PM<INF>2.5 measurements made at each monitoring station at least 6 times per year and applies to both automated and manual methods. Individual samplers or monitors are screened for bias and excessive imprecision. Estimates of integrated measurement precision and accuracy, in the form of 95 percent probability limits, for each designated PM<INF>2.5 method are determined for each reporting organization and on a national basis. Reporting organizations are defined as in section 3 of this Appendix. The results of the latter evaluation shall be used to review instrument and reporting organization performance. The absolute value of the 95 percent probability limits on a national basis for each designated method must be within 15 percent for the method to maintain its reference or equivalent method designation.
 6.1 Operational field test audits. For each SLAMS PM<INF>2.5 monitor, collocate a PM<INF>2.5 reference method sampler, referred to as an ``audit sampler,'' and operate it simultaneously with the SLAMS monitor at least 6 times per year. These collocated audits are required even for SLAMS PM<INF>2.5 monitors located at sites that have a collocated PM<INF>2.5 monitor as required under section 3.3 of this appendix, unless the collocated monitor is a PM<INF>2.5 reference method sampler and is a designated audit device as described in the Section 2.12 of the Quality Assurance Handbook (Reference 7). The collocated audit sampler shall be located between 2 and 4 meters from the SLAMS monitor, with its inlet at the same height above ground as the inlet of the SLAMS monitor. Calibration and operation of the audit sampler and analysis of the audit sample filter shall be as specified in the sampler's operation or instruction manual and in general accordance with the guidance provided in Section 2.12 of Reference 7. Calibration and operation of the SLAMS monitor shall be the same as for its routine SLAMS operation, and it shall not receive any special or non-scheduled service immediately prior to, or specifically associated with, the collocated sample collection. The 6 or more collocated PM<INF>2.5 measurement pairs shall be obtained at approximately equal intervals over the year, such as every other month, and shall be reported to the EPA as set forth in Section 4 of this Appendix for other precision and accuracy test results. All collocated measurements shall be reported, even those which might be considered invalid because of identified malfunctions or other problems occurring during the sample collection period. Collocated measurements shall be reported to EPA only for methods and analyzers approved for use in SLAMS monitoring under part 58 of this chapter. The EPA will calculate annual evaluations from the reported test measurements, as described in sections 6.2 and 6.3.
 6.2 Screening Test for Bias and Excessive Imprecision of Individual Monitors. This section describes a simple test, based on the [[Page 65855]] binomial distribution, that checks for gross bias or inadequate precision in the field operation of either the SLAMS monitor or the audit sampler. However, since the audit sampler is a reference method, the test results apply primarily to the SLAMS monitor. The test uses the collocated audit measurements described in section 6.1, and may be used with 4 to 12 measurement pairs.
 6.2.1 (1) For the annual evaluation, the EPA will calculate the relative percent difference (RPD) for each measurement pair obtained for the year as:
 [GRAPHIC] [TIFF OMITTED] TP13DE96.137 where
 C = the concentration measured by the SLAMS monitor, and C<INF>audit = the concentration measured by the audit sampler. (2) All collocated measurements will be used for this test, even those which might be considered invalid because of identified malfunctions or other problems occurring during the sample collection period.
 6.2.2 There are three situations that can develop from analyzing the collocated data:
 Situation A: All the RPD's are within 15% in absolute value. For situation A, the SLAMS monitor shows no indication of bias or inadequate precision and therefore passes this screening test. Situation B: Some or all of the RPD's are extreme in that they exceed 15% in absolute value, and the extreme RPD's all have the same sign (for example, -19, -21, -16). This may indicate a bias. For situation B, Table A-2 specifies the minimum number of extreme RPD's, all having the same sign, that indicates that the SLAMS monitor has a significant, unacceptable bias with respect to the audit reference method.
 Situation C: Some or all of the RPD's are extreme in that they exceed 15% in absolute value, and the extreme RPD's do not all have the same sign (for example, -17, +19, -18). This may indicate unacceptable precision. For situation C, Table A-2 specifies the minimum number of extreme RPD's, all not having the same sign, that indicate that the SLAMS monitor has excessive imprecision with respect to the audit reference method.
 6.2.3 If either bias (Situation B) or excessive imprecision (Situation C) is indicated by this screening test for a particular SLAMS monitor, the reporting organization will be notified by the EPA within 60 days after the end of the year that no monitors of the type (identified by its reference or equivalent method designation number) that failed the screening test shall be used for further SLAMS monitoring at any SLAMS site in the reporting organization unless and until the probable cause or causes of the test failure have been identified and corrected, the correction has been appropriately addressed in the applicable quality assurance plan, and the organization has received approval by the EPA Regional Office to resume use of monitors of the type identified for SLAMS purposes. General guidance in identifying and correcting common or typical types of such quality assurance problems for reference methods and Class I equivalent methods is provided in section 2.12 of Reference 7 of this appendix. Table A-2.--Table for Determining Bias or Excessive Inadequate Precision
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
 
 for Screening Test
 
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
 
 Situation C Situation B Number of Number of RPD's of RPD's of absolute absolute value over value over 15%--all 15%--all not having
 Number of measurement pairs having the the same
 Note: EPA no longer updates this information, but it may be useful as a reference or resource.
 
 same sign-- sign--that that indicate indicate excessive significant imprecision bias of the of the SLAMS SLAMS monitor monitor
 
 4............................................. 2 3 5............................................. 2 3 6............................................. 3 4 7............................................. 3 4 8............................................. 3 4 9............................................. 3 5 10............................................ 4 5 11............................................ 4 5
 12..................... 4 6
 6.2.4 The basis of this test is as follows: 6.2.4.1 For both instruments, the precision is assumed to be a percentage of the concentration being measured. The distributions of the instruments measurements are assumed to be normal, with an operating precision (1.96 x standard deviation) of no more than 15%. The relative percent difference (RPD) is then approximately normally distributed, with a standard deviation of about 15 x sqrt(2)/1.96 = 10.7%. Thus, the absolute value of RPD will exceed 15% approximately 20% of the time.
 6.2.4.2 In the first situation (situation A), all the RPD's are within 15% in absolute value, and the performance is acceptable. 6.2.4.3 When encountering a situation where RPD's are to one extreme or the other (situation B), one can set up the following hypotheses. Null Hypothesis: The mean measurements of both instruments are the same. Alternative Hypothesis: The mean of measurement of the SLAMS instrument is higher (lower) than the mean measurement of the audit instrument. The test of these hypotheses is based on the binomial distribution. Table A-2 gives the number of extreme values, for various numbers of measurement pairs, that would lead to a rejection of the null hypothesis in favor of the alternative hypothesis.
 6.2.4.4 When encountering the situation where RPD's are extreme in both directions (situation C), one can set up the following hypotheses. Null Hypothesis: The precisions of both instruments are less than or equal to 15% (2-sigma). Alternative Hypothesis: The precision of at least one instrument exceeds 15%. Again, the test is based on the binomial distribution, and Table A-2 gives the number of extreme values, for various numbers of measurement pairs, that would lead to a rejection of the null hypothesis in favor of the alternative hypothesis.
 6.2.4.5 These tests described above are stringent, using p=0.01, meaning that less than 1 time out of 100 would one expect to find the result randomly.
 6.2.4.6 As an example, suppose one takes 6 pairs of simultaneous measurements and finds that 4 of the 6 RPD's for the SLAMS monitor are greater than 15% and none of the remaining two RPD's are below--15%. Since there are 4 RPD's with absolute value above 15% and they all have the same sign (i.e. they are all above 15%), this example would be situation B. Table A-2 indicates that for situation B with 6 measurement pairs, 3 or more extreme RPD's means that the SLAMS monitor is biased (in this case, higher) than the audit (reference) method.
 6.3 Integrated Precision and Accuracy for Reporting Organizations and for Specific Methods. This section describes how integrated estimates of monitoring data quality are calculated for specific monitoring methods (as identified by a unique reference or equivalent method designation number) on a national basis and for each reporting organization. These estimates are based on the collocated audit measurements described in section 6.1.
 6.3.1 Annual evaluation. Using the collocated measurement pair data, as described in Section 6.1 for the applicable year, the EPA shall determine the operating precision for each designated method, on a national basis and for each reporting organization, as follows: 6.3.1.1. For each monitoring station for which PM<INF>2.5 data has been reported to AIRS during the year, calculate the percent difference (d<INF>i) for each measurement pair using equation 1 in section 5.1.1 of this Appendix, where Y<INF>i is the concentration measurement from the SLAMS monitor for the I-th audit measurement pair, X<INF>i is the concentration measurement from the audit sampler. Include only stations at which at least 4 collocated measurement pairs are available for the year, and only measurement pairs in which X<INF>i is above the limit for PM<INF>2.5 specified in section 5.3.1 of this Appendix.
 6.3.1.2 For each monitoring station for which PM<INF>2.5 data has been reported to AIRS, calculate the average (d<INF>j) and the standard deviation (S<INF>j) for the year for each station at which the method is used for SLAMS monitoring, using equations 2 and 3 [[Page 65856]] (respectively) in section 5.1.1 of this Appendix, where n is the number of measurement pairs reported for the year. Include only stations at which at least 4 collocated measurement pairs are available for the year.
 6.3.1.3 For each designated method and for each reporting organization, calculate the average of averages (D) and the pooled estimate of standard deviation (S<INF>a), using equations 4a and 5a (respectively) of Section 5.1.2, where k in this case is the number of stations in the reporting organization at which the method is used for SLAMS monitoring (and at least 4 measurement pairs are reported). Call these estimates D<INF>R,M and S<INF>R,M, where R identifies the reporting organization and M identifies the designated method.
 6.3.1.4 For each designated method, calculate the average of averages (D) and the pooled standard deviation (S<INF>a) at the national level using equations 4a and 5a (respectively) of Section 5.1.2, where k in this case is the number of sites nationwide at which the method is used for SLAMS monitoring (and at least 4 measurement pairs are reported). Call these estimates D<INF>national, M and S<INF>national, M, where M identifies the designated method. A 95 percent confidence interval shall also be determined for each national pooled standard deviation. 6.3.1.5 For each designated method, calculate the 95 percent probability limits for each reporting organization, using equations 6 and 7 of Section 5.1.2, where D=D<INF>R,M and S<INF>a=S<INF>R,M. Similarly, calculate the 95 percent probability limits for each method on a national basis, using equations 6 and 7 of Section 5.1.2, where D=D<INF>national,M and S<INF>a=S<INF>national,M. Note: Pooling individual site estimates of precision across a reporting organization or across the nation using equation 5a assumes that the individual site estimates of precision using equation 3 are reasonably homogeneous across the year for a designated method.
 6.3.2 Reporting organization method operational performance. A summary of the results calculated in section 6.3.1.5 shall be reported annually to the appropriate EPA Regional Office. If the absolute value of either the upper or lower probability limit for a reporting organization calculated in section 6.3.1.5 for any designated method is found to be greater than 15 percent or substantially higher than the corresponding limits calculated for the method on the national basis, the reporting organization shall be identified and notified by the EPA that its quality assurance in the operation of the particular PM<INF>2.5 method may be inadequate. Each reporting organization so identified and notified must demonstrate, through an appropriate quality assurance plan or modified plan, that it will achieve better performance in future monitoring operations using the method. General guidance in identifying and correcting common or typical types of such quality assurance problems for reference methods and Class I equivalent methods is provided in section 2.12 of Reference 7 of this appendix. 6.3.3 National method operational performance. If the absolute value of either the upper or lower probability limit calculated in section 6.3.1.5 for any designated method on a national basis is found to be greater than 15 percent, the method shall be deemed to have failed the annual operational performance assessment test. This result shall constitute a ground for cancellation of the reference or equivalent method in accordance with Sec. 53.11 of this chapter, and the EPA shall take the actions specified in that section within 150 days. References in Appendix A of Part 58
 
 Rhodes, R.C. Guideline on the Meaning and Use of Precision and Accuracy Data Required by 40 CFR part 58 appendices A and B. EPA-600/4-83/023. U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, June, 1983.
 
 ``American National Standard--Specifications and Guidelines for Quality Systems for Environmental Data Collection and Environmental Technology Programs.'' ANSI/ASQC E4-1994. January
 Available from American Society for Quality Control, 611 East Wisconsin Avenue, Milwaukee, WI 53202.
 
 ``EPA Requirements for Quality Management Plans.'' EPA QA/R-
 August 1994. Available from U.S. Environmental Protection Agency, ORD Publications Office, Center for Environmental Research Information (CERI), 26 W. Martin Luther King Drive, Cincinnati, OH 45268.
 
 ``EPA Requirements for Quality Assurance Project Plans for Environmental Data Operations.'' EPA QA/R-5. August 1994. Available from U.S. Environmental Protection Agency, ORD Publications Office, Center for Environmental Research Information (CERI), 26 W. Martin Luther King Drive, Cincinnati, OH 45268.
 ``Guidance for the Data Quality Objectives Process.'' EPA QA/ G-4. September 1994. Available from U.S. Environmental Protection Agency, ORD Publications Office, Center for Environmental Research Information (CERI), 26 W. Martin Luther King Drive, Cincinnati, OH 45268.
 
 ``Quality Assurance Handbook for Air Pollution Measurement Systems, Volume 1--A Field Guide to Environmental Quality Assurance.'' EPA-600/R-94/038a. April 1994. Available from U.S. Environmental Protection Agency, ORD Publications Office, Center for Environmental Research Information (CERI), 26 W. Martin Luther King Drive, Cincinnati, OH 45268.
 
 ``Quality Assurance Handbook for Air Pollution Measurement Systems, Volume II--Ambient Air Specific Methods (Interim Edition).'' EPA-600/R-94/038b. April 1994. Available from U.S. Environmental Protection Agency, ORD Publications Office, Center for Environmental Research Information (CERI), 26 W. Martin Luther King Drive, Cincinnati, OH 45268. [Note: Section 2.12 of Volume II is currently under development and will not be available from the CERI address until it is published as an addition to EPA/600/R-94/038b. Prepublication draft copies of section 2.12 will be available from Department E (MD-77B), U.S. EPA, Research Triangle Park, NC 27711, or from the contact identified at the beginning of this proposed rule].
 
 ``List of Designated Reference and Equivalent Methods.'' Available from U.S. Environmental Protection Agency, National Exposure Research Laboratory, Quality Assurance Branch, MD-77B, Research Triangle Park, NC 27711.
 
 Technical Assistance Document for Sampling and Analysis of Ozone Precursors. Atmospheric Research and Exposure Assessment Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711. EPA 600/8-91-215. October 1991.
 ``EPA Traceability Protocol for Assay and Certification of Gaseous Calibration Standards.'' EPA-600/R-93/224. September 1993. Available from U.S. Environmental Protection Agency, ORD Publications Office, Center for Environmental Research Information (CERI), 26 W. Martin Luther King Drive, Cincinnati, OH 45268.
 Paur, R.J. and F.F. McElroy. Technical Assistance Document for the Calibration of Ambient Ozone Monitors. EPA-600/4-79-057. U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, September, 1979.
 
 McElroy, F.F. Transfer Standards for the Calibration of Ambient Air Monitoring Analyzers for Ozone. EPA-600/4-79-056. U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, September, 1979.

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

Tables to Appendix A of Part 58

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

                                Table A-1.--Minimum Data Assessment Requirements

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

                                                                                                  Parameters

Method Assessment method Coverage Minimum frequency reported

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

Precision:

Automated methods for SO<INF>2, Response check at Each analyzer..... Once per 2 weeks.. Actual

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

     NO<INF>2, O<INF>3, and CO.              concentration                                               concentration \2\
                                   between .08 and                                             and measured
                                   .10 ppm (8 & 10                                             concentration \3\
                                   ppm for CO) \2\.                                            .

[[Page 65857]]

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

Manual methods: All methods Collocated 1 site for 1-5 Once per week..... Two concentration

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

     except PM<INF>25.                  samplers.           sites; 2 sites                          measurements.
                                                       for 6-20 sites; 3                                        
                                                       sites >20 sites;                                         
                                                       (sites with                                              
                                                       highest conc.).

PM<INF>25 methods................ Collocated 1 site for 1-10 Once per week..... Two concentration

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

                                   samplers.           sites; 2 sites                          measurements.
                                                       for 11-20 sites;
                                                       3 sites >20
                                                       sites; (sites
                                                       with highest
                                                       conc.).
Accuracy:

Automated methods for SO<INF>2, Response check at 1. Each analyzer; 1. Once per year; Actual NO<INF>2, O<INF>3, and CO. .03-.08 ppm,1,2 2. 25% of 2. Each calendar concentration \2\

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

                                   .15-.20 ppm;<SUP>1,2     analyzers (at       quarter.            and measured     
                                   .35-.45 ppm;<SUP>1,2     least 1).                               (indicated)      
                                   ,80-.90 ppm;<SUP>1,2                                             concentration \3\
                                   (if applicable).                                            for each level.

Manual methods for SO<INF>2, and Check of Analytical system. Each day samples Actual

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

     NO<INF>2.                          analytical                              are analyzed, at    concentration and
                                   procedure with                          least twice per     measured         
                                   audit standard                          quarter.            (indicated)      
                                   solutions.                                                  concentration for
                                                                                               each audit       
                                                                                               solution.

TSP, PM<INF>10................... Check of sampler 1. Each sampler; 1. Once per year; Actual flow rate

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

                                   flow rate.          2. 25% of           2. Each calendar    and flow rate    
                                                       samplers (at        quarter.            indicated by the 
                                                       least 1).                               sampler.

PM<INF>25........................ 1. Check of 1. Each sampler, 1. Minimum of 1. Actual flow

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

                                   sampler flow rate.  all locations.      every calendar      rate and flow    
                                                                           quarter, 4 checks   rate indicated by
                                                                           per year.           sampler.         
                                  2. Audit with       2. Each sampler,    2. Minimum of       2. Particle mass  
                                   reference method.   all locations.      every other         concentration    
                                                                           month, 6            indicated by     
                                                                           measurements per    sampler and by   
                                                                           year.               audit reference  
                                                                                               sampler.

Lead........................ 1. Check of 1. Each sampler... 1. Include with 1. Same as for

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

                                   sampler flow rate                       TSP.                TSP.             
                                   as TSP;.                                                                     
                                  2. Check of         2. Analytical       2. Each quarter...  2. Actual         
                                   analytical system   system.                                 concentration and
                                   with Pb audit                                               measured         
                                   strips.                                                     (indicated)      
                                                                                               concentration of 
                                                                                               audit samples    
                                                                                               (<greek-m>g Pb/  
                                                                                               strip).

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

\1\ Concentration times 100 for CO.                                                                             
\2\ Effective concentration for open path analyzers.                                                            
\3\ Corrected concentration, if applicable, for open path analyzers.

Appendix C--[Amended] 15. Appendix C, is amended by revising section 2.2 and adding sections 2.2.1 through 2.2.2.2 to read as follows: 2.2 Substitute PM samplers. 2.2.1 Substitute PM<INF>10 samplers. 2.2.1.1 For purposes of showing compliance with the NAAQS for particulate matter, a high volume TSP sampler described in Appendix B of part 50 of this chapter may be used in a SLAMS in lieu of a PM<INF>10 monitor as long as the ambient concentrations of particles measured by the TSP sampler are below the PM<INF>10 NAAQS. If the TSP sampler measures a single value that is higher than the PM<INF>10 24-hour standard, or if the annual average of its measurements is greater than the PM<INF>10 annual standard, the TSP sampler operating as a substitute PM<INF>10 sampler must be replaced with a PM<INF>10 monitor. For a TSP measurement above the 24-hour standard, the TSP sampler should be replaced with a PM<INF>10 monitor before the end of the calendar quarter following the quarter in which the high concentration occurred. For a TSP annual average above the annual standard, the PM<INF>10 monitor should be operating by June 30 of the year following the exceedance. 2.2.1.2 In order to maintain historical continuity of ambient particulate matter trends and patterns for PM<INF>10 NAMS that were previously TSP NAMS, the TSP high volume sampler must be operated concurrently with the PM<INF>10 monitor for a one-year period beginning with the PM<INF>10 NAMS start-up date. The operating schedule for the TSP sampler must be at least once every six days regardless of the PM<INF>10 sampling frequency. 2.2.2 Substitute PM<INF>2.5 samplers. 2.2.2.1 For purposes of showing compliance with the NAAQS for particulate matter, a PM<INF>10 monitor designated as a reference or equivalent method for PM<INF>10 under part 53 of this chapter may be used in a SLAMS in lieu of a PM<INF>2.5 monitor as long as the ambient concentration of particles measured by the PM<INF>10 monitor is below the PM<INF>2.5 NAAQS. If the PM<INF>10 monitor measures a single value that is higher than the PM<INF>2.5 24-hour standard, or the annual average of its measurements is greater than the PM<INF>2.5 annual standard, the PM<INF>10 monitor operating as a substitute PM<INF>2.5 monitor must be replaced with a PM<INF>2.5 monitor. For a PM<INF>10 measurement above the 24-hour PM<INF>2.5 standard, the PM<INF>10 monitor should be replaced with a PM<INF>2.5 monitor before the end of the calendar quarter following the quarter in which the high concentration occurred. For a PM<INF>10 annual average above the annual PM<INF>2.5 standard, the PM<INF>2.5 monitor should be operating by June 30 of the year following the exceedance. 2.2.2.2 In order to maintain historical continuity of ambient particulate matter trends and patterns for PM<INF>2.5 NAMS that were previously PM<INF>10 NAMS, the PM<INF>10 monitor must be operated concurrently with the PM<INF>2.5 monitor for a one-year period beginning with the PM<INF>2.5 NAMS start-up date. The operating schedule for the PM<INF>10 monitor must be at least once every six days regardless of the PM<INF>2.5 sampling frequency. 16. Appendix C amended by adding a new sections 2.4 through 2.4.6 to read as follows: 2.4 Approval of non-designated PM<INF>2.5 methods operated at specific individual sites. A method for PM<INF>2.5 that has not been designated as a reference or equivalent method as defined in Sec. 50.1 of this chapter may be approved for use for purposes of section 2.1 of this Appendix at a particular SLAMS under the following stipulations.
2.4.1 The method must be demonstrated to meet the comparability requirements (except as provided in this section 2.4.1) set forth in Sec. 53.34 of this chapter in each of the four seasons at the site at which it is intended to be used. For purposes of this [[Page 65858]] section 2.4.1, the requirements of 40 CFR 53.34 shall be modified as follows:
2.4.1.1 The method shall be tested at the site at which it is intended to be used, and there shall be no requirement for tests at any other test site.
2.4.1.2 For purposes of this section 2.4, the seasons shall be defined as follows: spring shall be the months of March, April, and May; summer shall be the months of June, July, and August; fall shall be the months of September, October, and November; and winter shall be the months of December, January, and February. 2.4.1.3 No PM<INF>10 samplers shall be required for the test, as determination of the PM<INF>2.5/PM<INF>10 ratio at the test site shall not be required.
2.4.1.4 The specifications given in Table C-4 of part 53 of this chapter for Class I methods shall apply, except that there shall be no requirement for any minimum number of sample sets with R<INF>j above 40 <greek-m>g/m\3\ for 24-hour samples or above 30 <greek-m>g/m\3\ for 48-hour samples. 2.4.2 The monitoring agency wishing to use the method must develop and implement appropriate quality assurance procedures for the method.
2.4.3 The monitoring agency wishing to use the method must develop and implement appropriate procedures for assessing and reporting the precision and accuracy of the method comparable to the procedures set forth in Appendix A of this part for designated reference and equivalent methods.
2.4.4 The assessment of network operating precision using collocated measurements with reference method ``audit'' samplers required under section 6 of Appendix A of this section shall be carried out semi-annually rather than annually (i.e., monthly audits with assessment determinations each 6 months). 2.4.5 Requests for approval under this section 2.4 must meet the general submittal requirements of sections 2.7.1 and 2.7.2.1 of this appendix and must include the requirements in sections 2.4.5.1 through 2.4.5.7 of this appendix.
2.4.5.1 A clear and unique description of the site at which the method or sampler will be used and tested, and a description of the nature or character of the site and the particulate matter that is expected to occur there.
2.4.5.2 A detailed description of the method and the nature of the sampler or analyzer upon which it is based. 2.4.5.3 A brief statement of the reason or rationale for requesting the approval.
2.4.5.4 A detailed description of the quality assurance procedures that have been developed and that will be implemented for the method.
2.4.5.5 A detailed description of the procedures for assessing the precision and accuracy of the method that will be implemented for reporting to AIRS.
2.4.5.6 Test results from the comparability tests required above.
2.4.5.7 Such further supplemental information as may be necessary or helpful to support the required statements and test results.
2.4.6 Within 120 days after receiving a request for approval of the use of a method at a particular site under this section 2.4 and such further information as may be requested for purposes of the decision, the Administrator will approve or disapprove the method by letter to the person or agency requesting such approval. 17. Appendix C is amended by adding a new section 2.5 to read as follows: 2.5 Approval of non-designated methods under Sec. 58.13(f). An automated (continuous) method for PM<INF>2.5 that is not designated as either a reference or equivalent method as defined in Sec. 50.1 of this chapter may be approved under Sec. 58.13(f) for use at a SLAMS for the limited purposes of Sec. 58.13(f). Such an analyzer that is approved for use at a SLAMS under Sec. 58.13(f), identified as correlated acceptable continuous (CAC) monitors, shall not be considered a reference or equivalent method as defined in Sec. 50.1 of this chapter by virtue of its approval for use under Sec. 58.13(f), and the PM<INF>2.5 monitoring data obtained from such a monitor shall not be otherwise used for purposes of part 50 of this chapter. 18. Appendix C is amended by revising the section 2.7.1 to read as follows: 2.7.1 Requests for approval under sections 2.4, 2.6.2, or 2.8 must be submitted to: Director, National Exposure Assessment Laboratory, Department E, (MD-77B), U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711. 19. Appendix C is amended by adding a new section 2.9 to read as follows: 2.9 Use of IMPROVE Samplers at a SLAMS. ``IMPROVE'' samplers may be used in SLAMS for monitoring of regional background concentrations of fine particulate matter. The IMPROVE samplers were developed for use in the Interagency Monitoring of Protected Visual Environments (IMPROVE) network to characterize all of the major components and many trace constituents of the particulate matter that impair visibility in Federal Class I Areas. These samplers are routinely operated at about 70 locations in the United States. IMPROVE samplers consist of four sampling modules that are used to collect twice weekly 24-hour duration simultaneous samples. Modules A, B, and C collect PM<INF>2.5 on three different filter substrates that are compatible with a variety of analytical techniques, and module D collects a PM<INF>10 sample. PM<INF>2.5 mass and elemental concentrations are determined by analysis of the 25mm diameter stretched Teflon filters from module A. More complete descriptions of the IMPROVE samplers and the data they collect are available elsewhere (References 5.2, 5.3, and 5.4 of this Appendix). 20. Appendix C, section 6.0 amended by adding references, 4 through 6 to read as follows: 6.0 References

* * * *
Eldred, R.A., Cahill, T.A., Wilkenson, L.K., et al., ``Measurements of fine particles and their chemical components in the IMPROVE/NPS networks,'' in ``Transactions of the International Specialty Conference on Visibility and Fine Particles,'' Air and Waste Management Association: Pittsburgh, PA, 1990; pp 187-196.
Sisler, J.F., Huffman, D., and Latimer, D.A.; ``Spatial and temporal patterns and the chemical composition of the haze in the United States: An analysis of data from the IMPROVE network, 1988- 1991,'' ISSN No. 0737-5253-26, National Park Service, Ft. Collins, CO, 1993.
Eldred, R.A., Cahill, T.A., Pitchford, M., and Malm, W.C.; ``IMPROVE--a new remote area particulate monitoring system for visibility studies,'' Proceedings of the 81st Annual Meeting of the Air Pollution Control Association, Dallas, Paper 88-54.3, 1988.

Appendix D--[Amended] 21. In Appendix D the first three paragraphs and Table 1 of section 1 are revised as follows:

SLAMS Monitoring Objectives and Spatial Scales The purpose of this appendix is to describe monitoring objectives and general criteria to be applied in establishing the State and Local Air Monitoring Stations (SLAMS) networks and for choosing general locations for new monitoring stations. It also describes criteria for determining the number and location of National Air Monitoring Stations (NAMS), Photochemical Assessment Monitoring Stations (PAMS), and core Stations for PM<INF>2.5. These criteria will also be used by EPA in evaluating the adequacy of the SLAMS/NAMS/PAMS and core PM<INF>2.5 networks. The network of stations which comprise SLAMS should be designed to meet a minimum of six basic monitoring objectives. These basic monitoring objectives are:
(1) To determine highest concentrations expected to occur in the area covered by the network;
(2) To determine representative concentrations in areas of high population density;
(3) To

Proposed Requirements for Designation of Reference and Equivalent Methods for PM<INF>2.5 and Ambient Air Quality Surveillance for Particulate Matter

2000................................ 600 760 161 5,966 6,127

4....................... 0.80-0.90 ...... 80-90

12..................... 4 6