Revised Requirements for Designation of Reference and Equivalent Methods for PM_2.5 and Ambient Air Quality Surveillance for Particulate Matter

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

[Federal Register: July 18, 1997 (Volume 62, Number 138)]
[Rules and Regulations]
[Page 38763-38854]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr18jy97-20]
[[Page 38764]]

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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Parts 53 and 58
[AD-FRL-5725-6]
RIN 2060-AE66

Revised Requirements for Designation of Reference and Equivalent
Methods for PM_2.5 and Ambient Air Quality Surveillance for
Particulate Matter

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

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SUMMARY: This final rule revises the 40 CFR part 58 ambient air quality
surveillance regulations to include provisions for PM_2.5
(particulate matter with an aerodynamic diameter less than or equal to
a nominal 2.5 micrometers), as measured by a new reference method being
published in 40 CFR part 50, Appendix L, elsewhere in this issue of the
Federal Register or by an equivalent method designed in accordance with
requirements being promulgated in 40 CFR part 53. In addition, this
rule also revises existing ambient air quality monitoring requirements
for PM₁₀ (particles with an aerodynamic diameter less than
or equal to 10 micrometers). These revisions address network design and
siting, quality assurance (QA) and quality control (QC), operating
schedule, network completion, system modifications, data reporting, and
other monitoring subjects.

EFFECTIVE DATE: This regulation is effective September 16, 1997.

ADDRESSES: All comments received relative to this rule have been placed
in Docket A-96-51, located in the Air Docket (LE-131), Environmental
Protection Agency, 401 M St., SW., Washington, DC 20460. The docket may
be inspected between 8 a.m. and 5:30 p.m., Monday through Friday,
excluding legal holidays. A reasonable fee may be charged for copying.

FOR FURTHER INFORMATION CONTACT: For general information, contact
Brenda Millar (MD-14), Monitoring and Quality Assurance Group,
Emissions Monitoring, and Analysis Division, Environmental Protection
Agency, Research Triangle Park, North Carolina 27711, Telephone: (919)
541-5651, e-mail: millar.brenda@email.epa.gov. For technical
information, contact Neil Frank (MD-14), Monitoring and Quality
Assurance Group, Emissions, Monitoring, and Analysis Division,
Environmental Protection Agency, Research Triangle Park, North Carolina
27711, Telephone: (919) 541-5560.

SUPPLEMENTARY INFORMATION:
Table of Contents
I. Authority
II. Introduction
A. Revision to the Particulate Matter NAAQS
B. Air Quality Monitoring Requirements
III. Discussion of Regulatory Revisions and Major Comments on 40 CFR
Part 53
A. Designation of Reference and Equivalent Methods for
PM_2.5
B. Reference Method Designation Requirements
C. Equivalent Method Designation Requirements
D. Proposed Reference and Equivalent Method Requirements
E. Changes to the Proposed Method Designation Requirements
IV. Discussion of Regulatory Revisions and Major Comments on 40 CFR Part 58
A. Overview of Part 58 Regulatory Requirements
B. Section 58.1 - Definitions
C. Section 58.13 - Operating schedule
D. Section 58.14 - Special purpose monitors
E. Section 58.15 - Designation of monitoring sites
F. Section 58.20 - Air quality surveillance: plan content
G. Section 58.23 - Monitoring network completion
H. Section 58.25 - System modification
I. Section 58.26 - Annual State monitoring report
J. Section 58.30 - NAMS network establishment
K. Section 58.31 - NAMS network description
L. Section 58.34 - NAMS network completion
M. Section 58.35 - NAMS data submittal
N. Appendix A - Quality Assurance Requirements for State and
Local Air Monitoring Stations (SLAMS)
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. Appendix F - Annual Summary Statistics
S. Review of Network Design and Siting Requirements for PM
T. Resources and Cost Estimates for New PM Networks
V. Reference
VI. Regulatory Assessment Requirements
A. Regulatory Impact Analysis
B. Paperwork Reduction Act
C. Impact on Small Entities
D. Unfunded Mandates Reform Act of 1995

I. Authority

Section 110, 301(a), 313, and 319 of the Clean Air Act (Act) as
amended 42 U.S.C. 7410, 7601(a), 7613, 7619.

II. Introduction

A. Revision to the Particulate Matter NAAQS

Elsewhere in this issue of the Federal Register, EPA announced
revisions to the national ambient air quality standards (NAAQS) for
particulate matter (PM). In that document EPA amends the current suite
of PM standards by adding PM_2.5 standards and by revising
the form of the current 24-hour PM₁₀ standard. Specifically,
EPA is adding two primary PM_2.5 standards set at 15
<greek-m>g/m3, annual mean, and 65 <greek-m>g/m3,
24-hour average. The annual PM_2.5 standard would be met when
the 3-year average of the annual arithmetic mean PM_2.5
concentrations is less than or equal to 15 <greek-m>g/m3
from single or multiple community-oriented monitors in accordance with
40 CFR part 50, Appendix K and requirements set forth in this final
rule. The 24-hour PM_2.5 standard would be met when the 3-
year average of the 98th percentile of 24-hour PM_2.5
concentrations at each population-oriented monitor within an area is
less than or equal to 65 <greek-m>g/m3.
EPA also retained the current annual PM₁₀ standard at
the level of 50 <greek-m>g/m3 which would be met when the 3-
year average of the annual arithmetic PM₁₀ concentrations at
each monitor within an area is less than or equal to 50 <greek-m>g/
m3. Further, EPA retained the current 24-hour
PM₁₀ standard at the level of 150 <greek-m>g/m3,
but revised the form such that the standard would be met when the 3-
year average of the 99th 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 final rule published elsewhere in this issue of the
Federal Register, EPA is also revising the current secondary standards
for PM by making them identical to the suite of primary standards. The
suite of PM_2.5 and PM₁₀ standards, in conjunction
with the establishment of a regional haze program under section 169A of
the Clean Air Act (the Act), are intended to protect against PM-related
welfare effects including soiling and materials damage and visibility
impairment.
As discussed in the part 50 final rule for the PM NAAQS, the
PM_2.5 standards are intended to protect against exposures to
fine particulate pollution, while the PM₁₀ standards are
intended to protect against coarse fraction particles as measured by
PM₁₀.
For PM_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_2.5 24-hour standard would serve
as a supplement to PM_2.5 annual standard

[[Page 38765]]

to provide additional protection against days with high
PM_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_2.5
annual standard) should be accomplished by comparing the annual mean
from a community-oriented monitor that is representative of average
community-wide exposure, or averaging the annual arithmetic means
derived from multiple, community-oriented monitoring sites, EPA took
into account several factors. As discussed in the part 50 final rule,
many of the community-oriented 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. 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_2.5 standard is 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 monitoring data
reflecting average community wide exposure would better reflect area-
wide PM_2.5 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 concept of average community
exposures is not appropriate for PM₁₀ 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 final
rule, the 24-hour PM_2.5 standard is intended to supplement
an annual PM_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_2.5 standard will 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_2.5 standard based on
monitoring data representative of community average air quality,
established in conjunction with a 24-hour standard based on the
population-oriented monitoring site with the highest measured values,
will provide the most appropriate target for reducing area-wide
population exposure to fine particle pollution and will be most
consistent with the underlying epidemiological data base.

B. Air Quality Monitoring Requirements

A new Federal Reference Method (FRM) for PM_2.5 is
promulgated in a new Appendix L to 40 CFR part 50. Section 319 of the
Act requires that uniform criteria be followed when measuring ambient
air quality. To satisfy these requirements, EPA established procedures
on February 10, 1975, in 40 CFR part 53 for the determination and
designation of reference or equivalent monitoring methods (40 FR 7049).
Accordingly, new provisions are added to 40 CFR part 53 so that each
reference method for PM_2.5, based on a particular sampler,
will be formally designed as such by EPA. Similarly, samplers
demonstrated as equivalent to the FRM can also be designated.
Furthermore, section 110(a)(2)(C) of the Act requires ambient air
quality monitoring for purposes of the State Implementation Plans
(SIPs) 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.1
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 PM measured as PM₁₀ on July 1, 1987 (52 FR
24740); provisions for PM_2.5 are published in this final
rule.
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1EPA intends to develop and propose for public comment a revised
Pollutant Standards Index that will address PM_2.5 as well
as PM₁₀, at a later date.
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On December 13, 1996, these rules were proposed in the Federal
Register as amendments to 40 CFR parts 53 and 58. The intent of the
monitoring method designations and air quality surveillance
requirements being promulgated today are to establish a revised
particulate matter monitoring network that will produce air quality
data utilizing uniform criteria for the purpose of comparison to the
revised primary and secondary PM NAAQS and to facilitate implementation
of a forthcoming regional haze program. The effective date of today's
monitoring regulation is September 16, 1997.

III. Discussion of Regulatory Revisions and Major Comments on 40
CFR Part 53

A. Designation of Reference and Equivalent Methods for PM_2.5

Provisions for EPA designation of reference and equivalent methods
for PM₁₀ and gaseous criteria pollutants have been
previously established and are set forth in 40 CFR part 53. On December
13, 1996, EPA proposed to amend part 53 to add new provisions to govern
designation of reference and equivalent method for PM_2.5.
The December 13th notice proposed new, detailed sampler testing and
other requirements that would apply to candidate reference and
equivalent PM_2.5 methods and describes how EPA proposed to
determine whether a candidate method should be designated as either a
reference or equivalent method. The notice further solicited public
comments on the proposed new provisions. Those provisions, modified
somewhat based on the public comments received, are being promulgated
today as amended part 53.
As for the other criteria air pollutants, reference methods for
PM_2.5 are intended to provide for uniform, reproduceable
measurements of PM_2.5 concentrations in ambient air to serve
as a measurement standard for the primary purpose of making comparisons
to the NAAQS. Equivalent methods for PM_2.5 allow for the
consideration and introduction of new and innovative PM_2.5
measurement technologies for this same purpose, provided such new
technologies can be shown to provide PM_2.5 measurements
comparable to reference measurements under a variety of typical
monitoring conditions.

B. Reference Method Designation Requirements

The new reference method for PM_2.5, described in 40 CFR
part 50, Appendix L contains a combination of design and performance
specifications to define the reference method PM_2.5 sampler.
The performance-based specifications for the reference method sampler
allow manufacturers to design and fabricate different samplers that
would meet all reference method requirements. Accordingly, multiple
PM_2.5 reference methods are expected to become available
from several manufacturers, as is the case for reference methods for
PM₁₀ and most gaseous criteria pollutants. Each reference
method for PM_2.5, based on a particular sampler, will be
formally designated as such by EPA under the new provisions added to 40
CFR part 53.

[[Page 38766]]

The requirements for designation of PM_2.5 reference
methods are set forth in subparts A and E of 40 CFR part 53. These
requirements include specific tests to show conformance with all design
and performance specifications, an operational field precision test, a
comprehensive operation/instruction manual, and documentation of an
adequate manufacturing and testing quality system. Subpart A, which has
been amended to add provisions for PM_2.5 methods, sets forth
the general requirements for both reference and equivalent methods and
for the process under which applications are submitted and reference
and equivalent method are designated. New subpart E, which is devoted
exclusively to PM_2.5 methods, describes the test procedures
and related requirements for candidate reference methods.

C. Equivalent Method Designation Requirements

The requirements for designation of equivalent methods for
PM_2.5 are also set forth in amended part 53. The general
requirements are set forth in subpart A. All candidate equivalent
methods are subject to the field tests for operational precision and
comparability to reference method measurements, which are specified in
subpart C. Both subparts A and C have been amended to include the
provisions for PM_2.5 methods.
To minimize the number and extent of performance tests to which
candidate equivalent methods must be subjected, three classes of
equivalent methods are defined.
Class I equivalent methods are based on samplers that have
relatively small deviations from the specifications for reference
method samplers. Therefore, in addition to the tests and other
requirements applicable reference method samplers, candidate Class I
equivalent samplers must be tested only to make sure that the
modifications do not significantly compromise sampler performance. The
additional test requirements for most Class I candidate equivalent
methods are a test for possible loss of PM_2.5 in any new or
modified components in the sampler inlet upstream of the sample filter,
and the field testing for comparability to reference method samplers.
These additional tests are described in subparts E and C, respectively.
Class II equivalent methods include all other PM_2.5
methods that are based on a 24-hour integrated filter sample that is
subjected to subsequent moisture equilibration and gravimetric mass
analysis. A sampler associated with a Class II equivalent method will
generally have one or more substantial deviations from the design or
performance specifications of the reference method, such that it cannot
qualify as a Class I equivalent method. 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 is
required for designation of Class II candidate equivalent methods, with
the specific tests required depending on the nature and extent of the
differences between the candidate sampler and the specifications for
reference method samplers. These tests may include a full wind tunnel
evaluation, a wind tunnel inlet aspiration test, a static fractionator
test, a fractionator loading test, a volatility test, and field testing
against reference method samplers. The tests and their specific
applicability to various types of candidate Class II equivalent method
samplers are set forth in the new subpart F.
Finally, Class III equivalent methods include any candidate
PM_2.5 methods that cannot qualify as either Class I or Class
II. This class includes any filter-based integrated sampling method
having other than a 24-hour PM_2.5 sample collection interval
followed by moisture equilibration and gravimetric mass. More
importantly, Class III also includes filter-based continuous or semi-
continuous methods, such as beta attenuation instruments, harmonic
oscillating element instruments, and other complete in situ monitor
types. Non-filter-based methods such as nephelometry or other optical
instruments will also fall into the Class III category.
The testing requirements for designation of Class III candidate
methods are the most stringent, because quantitative comparability to
the reference method will 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 must
be individually selected or specifically designed or adapted for each
such type of method. Therefore, EPA has determined 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, the specific test procedures and
performance requirements applicable to each Class III candidate method
will be determined by EPA on a case-by-case basis upon request, in
connection with each proposed or anticipated application for a Class
III equivalent method determination.

D. Proposed Reference and Equivalent Method Requirements

The proposed changes to 40 CFR part 53 to provide for designation
of reference and equivalent methods for PM_2.5 consisted of
revisions to subparts A and C, and new subparts E and F. The proposed
revisions to subpart A included new definitions applicable to
PM_2.5 methods and clarifications of existing definitions,
clarifications of the reference and equivalent method designation
requirements for all pollutants including the new classes of equivalent
methods for PM_2.5, and requirements for PM_2.5
samplers to be manufactured in an International Organization for
Standardization (ISO) 9001-registered facility (or equivalent).
Additional proposed changes included clarifications of the test data
and other information required to be submitted in applications for a
reference or equivalent method determination, clarification of
requirements for product warranty and content of operation or
instruction manuals, an increased time limit for processing
applications; and provisions for providing EPA with a candidate test
PM_2.5 sampler or analyzer to evaluate in connection with an
application for reference or equivalent method determination.
Revisions to subpart C included new procedures and specifications
for comparing candidate equivalent methods for PM_2.5 to
reference method samplers. The entirely new subpart E described the
technical procedures for testing the physical (design) and performance
characteristics of reference methods and Class I equivalent candidate
methods for PM_2.5. The new subpart F described the
procedures for testing the performance characteristics of Class II
equivalent methods for PM_2.5.

E. Changes to the Proposed Method Designation Requirements

The tests of the design and performance characteristics of
candidate samplers for designating reference methods as well as
equivalent methods are intimately related to the specifications for
reference methods in 40 CFR part 50, Appendix L. Many of the concerns
expressed by commenters regarding the reference method for
PM_2.5 in 40 CFR part 50, Appendix L also apply to some of
the provisions of part 53. Other comments were more directly concerned
with the provisions of 40 CFR part 53, and these comments are
summarized in this unit.

[[Page 38767]]

Several commenters addressed the responsibilities of EPA and
manufacturers in the method designation process. Specific comments
included the suggestions that: (1) It would be more appropriate for EPA
to conduct the necessary testing of a candidate method before
designating a reference method; (2) that EPA should clarify how it will
respond to possible poor sampler performance under extreme
environmental conditions encountered in some areas of the United
States, since the samplers are not required to meet such extreme
conditions; (3) that EPA should clarify that specifications for
completing sampler modifications or retrofits to work in nonstandard
environments should be included as part of a sampler purchase contract;
and (4) that EPA should clarify that the required method specifications
must be met throughout the warranty period and that the applicant
accepts responsibility and liability for ensuring conformance or
resolving nonconformities, including all necessary components of the
system, regardless of the original manufacturer.
The new provisions contained in the modified 40 CFR part 53 require
the applicant to submit information and documentation to demonstrate
that the applicant's candidate reference method sampler meets all
design specifications set forth in 40 CFR part 50, Appendix L. The
provisions also require the applicant to carry out specific tests to
demonstrate that the candidate reference or equivalent method meets all
performance specifications. The nature of these tests and the
requirement that they be carried out by the applicant rather than by
EPA is consistent with the previously established requirements in 40
CFR part 53 for designating reference or equivalent methods for other
criteria pollutants. Section 53.9 clearly states that a sampler sold as
part of a designated method must meet the applicable performance
specifications for at least 1 year after delivery. Section 53.9 further
requires that ISO 9001 registration of the manufacturing facility be
maintained and that a Product Manufacturing Checklist signed by a
certified ISO auditor be submitted annually to verify manufacturing
quality control.
In response to concerns about the performance of the sampler under
extreme weather conditions, EPA has established sampler specifications
that are intended to cover reasonably normal environmental conditions
at about 95 percent of expected monitoring sites. The performance tests
in subpart E address essentially all of these operational requirements.
Specification of the sampler performance for sites with extreme
environmental conditions would substantially raise the cost of the
sampler for users, most of whom do not require the extra capability.
EPA strongly recommends that users requiring operation of samplers
under extreme environmental conditions develop supplemental
specifications for modified samplers to cover those specific
conditions. Sampler manufacturers have indicated a commitment to
respond to such special operational needs.
Documentation is required to demonstrate that samplers to be sold
as reference or equivalent methods for PM_2.5 will be
manufactured under an effective quality control system. Although some
commenters supported the general quality assurance concepts contained
in the proposed method, several questioned the inclusion of the ISO
9001-registration requirement. EPA believes that the ISO 9001-
registration requirement and related provisions are the most cost-
effective way to ensure that samplers are manufactured in a facility
conforming to internationally recognized quality system standards.
Several comments questioned the proposed requirement that each
PM_2.5 sampler model be subjected to a specific annual
evaluation of performance and meet certain operating performance
specifications. In response to these comments, this requirement has
been deleted. However, EPA will review the performance of each
PM_2.5 sampler model on an annual basis, and if compelling
evidence indicates a significant bias or other operational problem, the
EPA Administrator may make a preliminary finding to cancel a reference
or equivalent method designation in accordance with the provisions of
Sec. 53.11 in subpart A.
Otherwise, the provisions of 40 CFR part 53 have been retained to
conform with the requirements described in 40 CFR part 50, Appendix L.
The proposed revisions to subparts A and C have been retained with no
substantive changes. However, minor technical and editorial changes
have been made to subparts A and C to clarify or simplify proposed
provisions. Subpart E has undergone extensive revision and
reorganization. Although these changes do not affect the objectives and
nature of the tests, they are intended to make the test requirements
easier to understand and the tests easier to perform. The changes were
based on EPA's own experience in performing tests of prototype
candidate samplers and on comments from prospective sampler
manufacturers. Subpart F has also been revised to some extent. The
changes to subpart F are not substantive in nature, but numerous
technical and editorial changes were made to clarify the test
requirements and make the tests, particularly the volatility test, more
straightforward to carry out.
All testing related to an application for a PM_2.5
reference or equivalent method determination under 40 CFR part 53 must
be carried out in accordance with American National Standards
Institute/American Society for Quality Control (ANSI/ASQC) E4
standards. These requirements are necessary to ensure that all samplers
or analyzers sold as reference or equivalent methods are manufactured
and tested to the high standards required to achieve the needed data
quality. These procedures are in keeping with the developing
international standards for manufacturing and testing in this and other
industries.

IV. Discussion of Regulatory Revisions and Major Comments on Part 58

The following discussion presents an overview of the final part 58
monitoring regulation. This is followed by a detailed discussion of the
basic concepts outlined in the December 13, 1996 monitoring proposal
and addresses those comments received on the proposed part 58
regulations that EPA considered to be most relevant to the changes and
additions adopted in the final rule. Comments not addressed in this
preamble are found in a Summary and Response to Comment document that
has been placed in Docket A-96-51. Those parts of the proposed
regulations which were not commented on have not been changed. The
items are discussed in the order in which they appear in the regulation.

A. Overview of Part 58 Regulatory Requirements

The requirements set forth in this rule simultaneously preserve the
underlying intent of the revised NAAQS and respond positively to the
very substantial and reasoned comments received on the proposal.
Specifically, the major monitoring requirements and principles set
forth by the revised part 58 regulation include:
1. PM_2.5 network design. Community-oriented (core)
monitors that represent community-wide average exposure, form the basis
of PM_2.5 network design. This approach is consistent with
the data bases used to develop the NAAQS. While all population-oriented
monitoring locations are eligible for comparison to the 24-hour
PM_2.5 NAAQS, only locations representative of neighborhood
or larger spatial scales

[[Page 38768]]

are eligible for comparison to the annual NAAQS. Community monitoring
zones with constrained criteria may be also used to define monitors
acceptable for spatial averaging for comparison to the annual NAAQS.
Monitoring for regional transport and regional background is required
to assist with implementation of the air quality management program.
The combination of emphasis on well-sited community-oriented monitors
and the feasibility by the States to select the preferred community
monitoring approach reduces complexity associated with network design
and planning. The number of required core PM_2.5 State and
Local Air Monitoring Stations (SLAMS), and other PM_2.5 SLAMS
results in a minimum national requirement of approximately 850
PM_2.5 sites (compared to 629 proposed); the total
PM_2.5 network is projected to approach 1,500
PM_2.5 sites. Exceptions to the minimum number of required
samplers may be approved by the EPA Regional Administrator. As
proposed, the mature network of 1,500 PM_2.5 sites would be
in place within 3 years. The phase-in of the required network has been
reduced from 3 to 2 years.
2. PM₁₀ monitoring networks. Requirements for
PM₁₀ network design and siting are unchanged. Reductions in
PM₁₀ networks are encouraged in areas of low concentrations
where the PM₁₀ NAAQS are not expected to be violated.
3. Sampling frequencies. The sampling frequencies stipulated in 40
CFR 58.13 for both PM_2.5 and PM₁₀, have been
modified to reflect a one in 3-day minimum requirement. Required every
day sampling at certain core sites may be reduced to one in 3-day
sampling after at least 3 complete years of data collection with a
reference or equivalent method or when collocated with a correlated
acceptable continuous (CAC) fine particulate monitor; background and
regional transport may also sample once every third day. Exceptions to
the minimum requirement may be approved by the EPA Regional
Administrator for seasonal or year-round sampling.
4. Chemical speciation. A modest chemical speciation network of 50
PM_2.5 sites that provides a first order characterization of
the metals, ions, and carbon constituents of PM_2.5 is a
requirement of this rule. These sites will be part of the National Air
Monitoring Stations (NAMS) network and will provide national
consistency for trends purposes and serve as a model for other chemical
speciation efforts. This required network represents a small fraction
of all the chemical speciation work that EPA expects to support with
Federal funds. Additional efforts may be used to enhance the required
network and tailor the collection and analysis of speciated data to the
needs of individual areas.
5. Quality assurance. The QA program is collectively based on a
variety of QA tools resulting in a program which is more efficient,
less costly, and relaxes the burden on State and local agencies. The
key program requirements include:
a. Independent field audits with a PM_2.5 FRM are used to
evaluate the bias of PM_2.5 measurements. The number of
PM_2.5 audited sites compared to the proposal are reduced
from all non-collocated sites to 25 percent of all SLAMS sites
(including NAMS) and the audit frequency per site is reduced from 6 to
4 visits per year.
b. Flow checks will also be used to evaluate bias of
PM_2.5 and PM₁₀ measurements and are conducted on
a quarterly basis as proposed.
c. Collocation with PM_2.5 FRM and Federal Equivalent
Methods (FEM) samplers at SLAMS sites is used to judge precision. The
number of collocated sites per reporting organization is 25 percent of
all PM_2.5 SLAMS sites (20 percent were proposed) and
approximately 20 percent of all PM₁₀ SLAMS sites (which is
current practice).
d. Systems audits are used to evaluate an agency's QA system and
will be performed by EPA every 3 years as originally proposed.
In an effort to assist the State and local agencies in achieving
the data quality objectives of the PM_2.5 monitoring program,
an incentive program has been established that is based on network
performance and maturity that can reduce these QA requirements.
6. Moratorium on the use of special purpose monitor (SPM) data. The
moratorium on the use of PM_2.5 data (Sec. 58.14) collected
by SPMs, has been changed from the first 3 calendar years following the
effective date of this rule to the first 2 complete calendar years of
operation of a new SPM. If such monitors produce valid data for more
than 2 years, then all historical data for that site may be used for
regulatory purposes.
7. Monitoring methodology. Appendix C has been revised to allow the
use of Interagency Monitoring of Protected Visual Environments
(IMPROVE) samplers at regional transport and regional background sites
to satisfy the SLAMS requirements.
8. PM monitoring network description. The State shall submit a PM
monitoring network description to the EPA Regional Administrator by
July 1, 1998, which describes the PM monitoring network, its intended
community monitoring approach for comparison to the annual
PM_2.5 standard, use of non-population-oriented special
purpose PM_2.5 monitors or alternative samplers, and proposed
exceptions to EPA's requirements for minimum number of monitors or
sampling frequency. The description shall be available for pubic
inspection and EPA shall review and approve/disapprove the document
within 60 days. A State air monitoring report with proposed network
revisions, if any, shall be submitted annually.
EPA believes that the aforesaid revisions to the rule, as proposed,
provide a firm basis for the uniform implementation of a national
particulate monitoring network which is responsive to a revised NAAQS
expressed as PM_2.5. The following is a section-by-section
discussion of comments received and any resulting modifications to the
proposal.

B. Section 58.1 - Definitions

EPA proposed to add several definitions applicable to PM
monitoring. This consisted of revising the definition of the term
traceable and definitions of the terms Consolidated Metropolitan
Statistical Area (CMSA), core SLAMS, equivalent methods, Metropolitan
Statistical Area (MSA), monitoring planning area (MPA), monitoring
plan, PM_2.5, Primary Metropolitan Statistical Area (PMSA),
population-oriented, reference method, spatial averaging zone (SAZ),
SPM fine monitors, and Annual State Monitoring Report. In response to
comments, EPA is modifying the proposed approach and is introducing new
terminology and definitions. First, EPA is changing the definition of
core SLAMS monitors to describe community-oriented monitors that are
representative of neighborhood or larger spatial scales and will be key
monitoring entities in the new PM_2.5 SLAMS network. As
discussed later, a subset of these monitors will be required to sample
everyday in the most populated metropolitan areas with the stated
emphasis on community-oriented monitoring. Although very important, the
background and regional transport monitors in the SLAMS network are no
longer called core sites. Secondly, EPA is replacing the definition of
spatial averaging zone with a definition of community monitoring zone
(CMZ). This is consistent with the intent of the annual
PM_2.5 standard, that is to be judged at monitoring stations
that are representative of community-wide air quality. EPA is also
renaming the PM monitoring plan as the PM monitoring network
description. EPA's rationale for

[[Page 38769]]

these changes, together with a more complete description of community
monitoring zones, are discussed in 40 CFR part 58, Appendix D.
In addition, several commenters addressed the definition of
population-oriented monitoring, objecting to the narrowness of the
definition with respect to industrial areas, and noting that if people
are present in an area, the site should be considered population-oriented.
EPA assessed these comments and concluded that the definition of
population-oriented monitoring or sites proposed in Sec. 58.1 is
essentially appropriate and as such will provide monitoring agencies
with the flexibility to design networks that are consistent with the
population-oriented approach described by the PM_2.5
standards. Therefore EPA is retaining this definition in the final rule
with a minor simplifying change as follows: population-oriented
monitoring (or sites) applies to residential areas, commercial areas,
recreational areas, industrial areas and other areas where a
substantial number of people may spend a significant fraction of their
day. The definition of population-oriented monitoring will be further
deliniated in future EPA guidance. As proposed, the final rule states
that all population-oriented PM_2.5 monitoring locations
shall be eligible for comparison to both the 24-hour PM₁₀
and PM_2.5 standards. In order to make these concepts clearer
for the final rule, however, several changes to the proposed language
were made in the final rule regarding eligibility of monitoring sites
for comparisons to the PM_2.5 NAAQS. First, the new
PM_2.5 network will place emphasis on community-oriented
monitoring for making comparisons to both the annual and 24-hour
PM_2.5 NAAQS. Secondly, as proposed, unique population-
oriented microscale and middle-scale monitoring sites shall only be
used for comparisons to the 24-hour NAAQS. Furthermore, violations
detected at rural background and regional transport sites are more
appropriately addressed by the implementation program which EPA is
developing.

C. Section 58.13 - Operating Schedule

EPA proposed that core PM_2.5 SLAMS (including NAMS and
core SLAMS collocated at Photochemical Assessment Monitoring Stations
(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 one in 6-day sampling would be
permitted. The proposal stated that 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). The proposed and final rule state that special purpose
monitors may sample on any sampling schedule. The proposal also
recognized that 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
FRMs or Class I equivalent samplers (under the provisions of part 53)
that will simplify the data collection process. Finally, EPA proposed
that alternative PM_2.5 operating schedules that combine
intermittent sampling with the use of acceptable continuous fine
particulate samplers are approvable at some core sites. This
alternative was intended to give the States additional flexibility in
designing their PM_2.5 monitoring networks and to permit data
from continuous instruments to be telemetered. This would facilitate
public reporting of fine particulate concentrations, and allow air
pollution alerts to be issued, and allow episodic controls to be
implemented (as currently done in woodburning areas for
PM₁₀). Furthermore, this alternative 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 of this rule. As proposed, applicability does not apply to
areas with population greater than 1 million during the first 2 years
of required sampling.
Many commenters supported daily PM_2.5 sampling, citing
the need to target sources, aid enforcement, and provide exposure
measurements for future community health studies. Additionally,
commenters supported daily PM_2.5 sampling to cover the most
polluted and most populated areas and to capture all violations. Other
commenters supported daily sampling but suggested limiting it to key
locations or seasons (e.g., only the largest metropolitan areas or
those areas with the highest PM_2.5 concentrations, only
during seasons when high values are likely). Other commenters suggested
allowing a reduction in sampling frequency to one in 6 days under
certain conditions; for example, at sites that have demonstrated
attainment, at sites with CAC analyzers, following the third year of
data collection, and during the portion of the year with low
PM_2.5 concentrations at a site with a district seasonal
pattern.
In addition, a number of commenters suggested a delay of everyday
sampling until the Class I equivalent samplers are available. It was
noted that over the short-term, only designated manual samplers capable
of collecting single 24-hour samples, could be available. Consequently,
to meet an everyday sampling schedule, several samplers would need to
be installed at each everyday sampling site to satisfy the daily
schedule, and cover weekend and holiday sampling periods.
Based on its review of these comments, EPA is retaining its
everyday sampling schedule for certain community-oriented (core) SLAMS
(i.e., two monitoring sites in each MSA greater than 500,000 population
and SLAMS collocated at PAMS for a total of 313 nationwide). The
remaining SLAMS including NAMS and other core SLAMS are required to
sample every third day.
Because of concerns over the potential unavailability of Class I
sequential samplers, EPA is allowing a waiver of the everyday or every
third day sampling schedule, when appropriate, in those situations
where such sampling is not needed. This waiver would expire 1 calendar
year from the time a sequential sampler has been approved by EPA. When
the waiver is granted for every day sampling, one in 3-day sampling
would be required. As proposed, EPA encourages the use of a
supplemental CAC analyzer as a means of facilitating a reduction of the
reference or equivalent method everyday sampling schedule to once in 3
days. The CAC monitoring option, however, will not be allowed in areas
greater than 1 million population that have high PM_2.5
concentrations during the first 2 years of daily data collection. A
minimum frequency of one in 6-day sampling is still required during
periods for which exemptions to everyday or every third day sampling
are allowed for PM_2.5 SLAMS.
For PM₁₀, the EPA Administrator proposed that one in 6-
day sampling should be sufficient to support the proposed
PM₁₀ NAAQS and a less dense monitoring network would also be
needed.
A number of commenters supported the typical one in 6-day sampling
frequency for PM₁₀. On the other hand, a number of
commenters opposed the proposed reduction in PM₁₀ sampling
frequency to one in 6 days, stating that one in 6-day sampling is
inadequate to evaluate impacts on the 24-hour PM₁₀

[[Page 38770]]

standard, especially in areas with episodic events or localized hot
spots, and that extreme pollutant conditions could be missed.
In response to the general concerns that sampling for
PM₁₀ is not sufficient and in accordance with the choice of
the 99th percentile as the form of the 24-hour PM₁₀
standards as discussed in 40 CFR part 50, EPA has changed the minimum
required sampling frequency from one sample every 6 days to one sample
in every 3 days.
The specified minimum sampling frequency of one in 3 days for
PM_2.5 and PM₁₀ will provide for a more
statistically stable representation of actual air quality at each
monitor as discussed in 40 CFR part 50. Further, increasing the
sampling frequency from one in 6- to one in 3-days will ensure that the
24-hour NAAQS comparisons are not based on the highest measured values
per year, and thus will significantly reduce the chances of incorrectly
classifying a ``clean'' area as nonattainment, and at the same time
provide enough information to confidently classify ``dirty'' areas as
nonattainment without requiring those areas to sample every day.
EPA believes that once in 6-day sampling is sufficient to estimate
an annual mean concentration for PM_2.5 or PM₁₀.
Furthermore, every day or every third day sampling is not generally
needed during periods of the lowest ambient PM concentrations.
Therefore, EPA is allowing exemptions to the every day or the one in 3-
day sampling requirement to individual areas with the approval of the
EPA Regional Administrator, in accordance with forthcoming EPA
guidance. In general, exemptions to the minimum one in 3-day sampling
frequency will be approvable when existing information suggests that
maximum 24-hour measurements are less than the level of the standard.
In these cases, a minimum of one in 6-day sampling will be required to
ensure that sufficient data are available to calculate an annual
average concentration. Areas adopting less frequent sampling would be
advised of the risks involved in such a choice; namely, that a single
high value in 1 year could end up causing the area to be declared in
violation of the 24-hour NAAQS. The guidance will also recommend that
more frequent sampling be considered for those areas that are
relatively close to the level of the standard. For example, areas whose
PM_2.5 or PM₁₀ data indicate that they meet the
annual PM NAAQS, but have the potential to not meet the 24-hour PM
NAAQS will be encouraged to sample everyday for PM_2.5 or
PM₁₀, as appropriate, during the high PM seasons in order to
better assess their status to the standards. While such an option may
be more costly for individual areas, the risk of inaccurately declaring
an attainment area to be nonattainment would be reduced.

D. Section 58.14 - Special Purpose Monitors

EPA proposed that special purpose monitoring (SPM) is needed in a
new PM_2.5 monitoring program 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. It was proposed, however, that data from SPMs would not be
used for attainment/nonattainment designations if the monitor is
located in an unpopulated area, if the monitoring method is not a
reference or equivalent method or does not meet the requirements of
section 2.4 of 40 CFR part 58, Appendix C. Moreover, in order to
encourage the deployment of SPMs, EPA proposed 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.
Numerous commenters opposed the proposed 3-year exclusion of SPM
data as a basis for NAAQS violations, noting that all measured
violations from all monitors should be used for nonattainment
designations. Other commenters supported the exclusion, suggesting that
SPM data should always be considered exploratory in nature and should
remain exempt from inclusion in regulatory data bases.
EPA has revisited its position on SPMs in light of these comments.
In order to encourage the deployment of SPMs, EPA has decided to
continue to provide States with the flexibility to exempt SPM data from
regulatory use, but limit the period of the moratorium to the first 2
complete calendar years of operation of a new SPM. Given the currently
limited amount of PM_2.5 data and the complexity of the
PM_2.5 air quality problem, the Agency feels that this
approach still provides a significant incentive for States to engage in
additional monitoring and thereby collect data that would supplement
the data collected at SLAMS sites. This can be very helpful for
establishing an optimum network design, for a better understanding of
the impacts of specific emission sources, and for other planning
purposes. If a monitoring site satisfies all applicable part 58
requirements including use of reference or equivalent methods, meeting
siting criteria, and other requirements as explained in Sec. 58.14 and
it continues to collect data beyond the first 2 complete calendar years
of its operation, the data from such SPM sites would then be generally
eligible for comparisons to the NAAQS. One exception is when a
monitoring agency intends to evaluate a special situation which is not
representative of population-oriented monitoring. In this case, the
data from the special purpose monitor would not be used for comparison
to the PM_2.5 standards. A second exception is when the
agency intends to evaluate a unique impact area that represents a small
spatial scale (micro or middle). In this case, the site would only be
eligible for comparison to the 24-hour NAAQS. Although SPM data will be
exempt from regulatory use during the 2-year moratorium, EPA emphasizes
that SPM data should nevertheless be considered in the State's PM
monitoring network description and in the design of its overall SLAMS
network. Moreover, SPM sites reporting values greater than the level of
a NAAQS should be considered during the annual network review in
accordance with Sec. 58.25, and summary data from SPM sites must be
included in the annual State Air Monitoring report described in
Sec. 58.26.

E. Section 58.15 - Designation of Monitoring Sites

The proposed monitoring regulations defined categories of sites
that would be eligible for comparisons to the annual or 24-hour NAAQS.
This included certain sites that could be used for comparison to both
standards (B sites), to only the daily standard (D sites) and certain
special purpose monitors (O sites) that potentially would not be used
for comparison to any standard. Due to significant concern regarding
the complexity of implementing those concepts to handle a small number
of unique monitoring situations, the final rule has eliminated the
coding of sites as type B, D, and O sites. Therefore, Sec. 58.15 has
been deleted in its entirety. The principal reasons also include the
emphasis on community-oriented monitors, the new terminology and
modified approach associated with CMZs, and more precise descriptions
of SLAMS and SPMs. The final rule provides a more streamlined and
simplified monitoring approach that retains the basic community average
air quality exposure tenets of the PM_2.5 annual NAAQS and,
as proposed,

[[Page 38771]]

recognizes that population-oriented hot spot monitoring may be more
reflective of situations applicable to the purposes of the 24-hour
PM_2.5 standard.
The changes to community monitoring and site categorization are
well integrated. EPA agrees with public comment that the proposed
spatial averaging approach may not have been properly communicated by
suggesting that it allowed averaging of monitors across widely
disparate areas not reflective of average community-oriented exposure
and a homogeneous emission source mix. EPA believes that by clarifying
the criteria that determine which monitors can be averaged together
(i.e., monitors in areas affected by similar emission sources), along
with emphasizing that well sited community-oriented monitors should be
used, environmental equity concerns and related issues are effectively
addressed. First, a single SLAMS or SPM that adequately represents a
local area can reflect its own community monitoring area. If its annual
average concentrations are more than 20 percent higher than the
surrounding average PM_2.5 air quality, it would not be
eligible to be averaged in with the surrounding sites of the larger
geographic domain. In addition, unique population-oriented hot spot
impact sites are not eligible for comparison to the annual
PM_2.5 NAAQS and are only eligible for comparison to the 24-
hour NAAQS. Additional details about CMZs are provided later.

F. Section 58.20 - Air Quality Surveillance: Plan Content

Although no comments were received on proposed changes to this
section, the title was inadvertently stated as Plan Control; this title
has been changed to Plan Content. In addition, the first sentence of
paragraph (d) has been changed by deleting the words ``section 2.8 of''
and the words ``as well as the minimum requirements for networks of
SLAMS stations for PM_2.5 described in section 2.8.2 of 40
CFR part 58, Appendix D.'' Since Sec. 58.20 requires an annual review
of the air quality surveillance system for all SLAMS, these changes
were instituted for clarity. The reference to PM_2.5 in the
third sentence of Sec. 58.20 was retained to ensure that the review
includes the unique requirements of the PM_2.5 monitoring
network.
The proposal indicated that a detailed Particulate Matter
Monitoring Plan (see Sec. 58.1, as proposed) must be prepared by the
affected air pollution control agency and submitted to EPA for
approval. This plan was designed to comprehensively describe the
Agency's PM_2.5 and PM₁₀ air quality surveillance
networks. Comments received noted that the term PM monitoring plan
could be confused with the network description required by Sec. 58.20.
Accordingly, EPA has replaced references to the ``PM Monitoring Plan or
monitoring plan'' in this final rule with references to the
``particulate matter monitoring network description or PM monitoring
network description.'' The Agency notes, however, that the rule
published today requires a more expanded and comprehensive network
description for PM than has previously been required for other
networks. Therefore, a new paragraph (f) has been added to Sec. 58.20
to delineate the requirements for PM monitoring network descriptions.
According to Sec. 58.20(e), as amended, this network description must
be submitted to the EPA Regional Administrator for approval.
To ensure opportunities for public review and inspection of the
monitoring network, States must maintain information and records on
such items as the station location, monitoring objectives, spatial
scale of representativeness, optional CMZs, and schedule for completion
of the network. Such information and records are included in a State's
PM monitoring network description. The PM monitoring network
description prepared by States and submitted to EPA for approval should
be viewed as a long-term network of SLAMS and NAMS sites that meet the
variety of monitoring objectives specified in 40 CFR part 58, Appendix
D of these regulations. These objectives include determining compliance
with air quality standards, developing appropriate control strategies
as required, and preparing short- and long-term air quality trends.
However, modifications to the network can be made without a formal SIP
revision thus encouraging States to make any needed yearly (or
alternate schedule as determined by the EPA Regional Administrator)
changes to the SLAMS network to make it more responsive to data needs
and resource constraints. In order to avoid making major modifications
to the PM monitoring network description during the annual review, the
detailed network, including monitoring planning areas and CMZs, should
be carefully planned and designed to provide a stable base of air
quality data. Since no formal SIP revision (that entails Federal
Register proposal and public comment) is required for the PM monitoring
network description revisions, EPA encourages public involvement in the
review of a State's PM monitoring network description particularly when
the spatial averaging monitoring approach is selected for comparisons
to the annual standard.

G. Section 58.23 - Monitoring Network Completion

EPA proposed that the PM networks would be expected to be completed
within 3 years of the effective date of promulgation. While new
PM_2.5 networks are developed, reductions in existing
PM₁₀ networks would be considered. The proposal stated that
during the first year, a minimum of one monitoring planning area per
State would be required to have core PM_2.5 SLAMS. This area
would be selected by the State according to the likelihood of observing
high PM_2.5 concentrations and according to the size of the
affected population. In addition, one PM_2.5 site was
proposed to be collocated at one PAMS site in each of the PAMS areas.
During the second year, all other core population-oriented
PM_2.5 SLAMS, and all core background and transport sites,
were proposed to be fully operational. During the third year, any
additional required PM_2.5 (non-core) SLAMS was proposed to
be fully deployed and all NAMS sites would be selected from core SLAMS
and proposed to EPA for approval.
Several commenters discussed the proposed phase-in schedule. One
commenter supported an accelerated phase-in schedule, while other
commenters supported a longer phase-in period. Several State commenters
expressed reservations about their ability to meet the proposed phase-
in schedule, due to limited resources and the unavailability of
monitoring equipment. One commenter felt that the phase-in should
require one core monitor in each of a few geographically diverse areas
per State, as this would provide more valuable information than only
one per MPA.
As noted in the comments on 40 CFR part 58, Appendix D, a large
number of commenters cited the immediate need for an expansive
PM_2.5 monitoring network to provide adequate monitoring data
to satisfy the monitoring objectives of the SLAMS network, in
particular, to provide 3 years of PM_2.5 data in order to
make comparisons with the NAAQS. As noted in the discussion below on
resources and costs, the Agency's grant allocations for fiscal years
1997-1998 include significant resources to accelerate the
implementation schedule and increase the number of monitoring sites
included in today's final rule. In view of these actions, the Agency is
accelerating the SLAMS monitoring

[[Page 38772]]

network completion schedule to require at least one core monitor in
each MSA greater than 500,000 population plus one PM_2.5 site
to be collocated with a PAMS site in each PAMS area and at least 2
additional SLAMS per State to be in operation by 1998; to require all
other required SLAMS including required regional transport and regional
background sites to be in operation by 1999; and to encourage all
additional sites (to complete the network) to be in operation by 2000.
In addition, the States should have at least one core SLAMS to be
deployed in all areas expected to have the potential for high
PM_2.5 concentrations, in accordance with EPA guidance, to be
in operation by 1998 which will be supported with funding from EPA's
section 105 grant program.

H. Section 58.25 - System Modification

The preamble to the proposal noted that although no changes to the
regulatory language were proposed for this section, the annual
monitoring system modifications review must include changes to
PM_2.5 site designations (e.g., NAAQS comparison sites), and
the number or boundaries of monitoring planning areas and/or spatial
averaging zones, now referred to as community monitoring zones. This
information is included for explanatory purposes only and does not
necessitate changes to the regulatory language.

I. Section 58.26 - Annual State Monitoring Report

Under the current regulations, States are required to submit an
annual SLAMS data summary report. EPA proposed that this report shall
be expanded to: (1) Describe the proposed changes to the State's PM
Monitoring Network Description, as defined in Sec. 58.20; (2) include a
new brief narrative report to describe the findings of the annual SLAMS
network review, reflecting within the year and proposed changes to the
State air quality surveillance system; and (3) provide information on
PM SPMs and other PM sites noted in the PM monitoring network
description 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 for EPA to ensure that a proper mix of
permanent and temporary monitoring locations are used and that
populated areas throughout the Nation are monitored, and to provide
needed flexibility in the State monitoring program.
In addition, the proposed changes to the PM monitoring network
description included changes to existing PM networks. The proposed
changes to existing PM networks included modifications to the number,
size, or boundaries of MPAs or SAZ's, number and location of PM SLAMS;
number or location of core PM_2.5 SLAMS; alternative sampling
frequencies proposed for PM_2.5 SLAMS (including core
PM_2.5 SLAMS and PM_2.5 NAMS); core
PM_2.5 SLAMS to be designated PM_2.5 NAMS; and PM
SLAMS to be designated PM NAMS. SPM's with measured values greater than
the level of the NAAQS would become part of the SLAMS network. The
proposed changes would be developed in close consultation with the
appropriate EPA Regional Office and submitted to the appropriate
Regional Office for approval. The portion of the document pertaining to
NAMS would be submitted to the EPA Administrator (through the
appropriate Regional Office).
Finally, as a continuation of current regulations, the States would
be required to submit the annual SLAMS summary report and to certify to
the EPA Administrator that the SLAMS data submitted are accurate and in
conformance with applicable part 58 requirements. Under the proposed
revisions, States would also be required to submit annual summaries of
SPM data to the EPA Regional Administrator for sites included in their
PM monitoring network description and to certify that such data are
similarly accurate and likewise in conformance with applicable part 58
requirements or other requirements approved by the EPA Regional
Administrator, if these data are intended to be used for SIP purposes.
All of the proposed changes described above did not receive substantive
comment and were retained in the final rule.
During the first 3 years following promulgation, the proposal
stated that the State's PM monitoring description (changed to PM
monitoring network description) and any modifications of it would 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 EPA Regional Administrator, with review and approval/
disapproval by the EPA Regional Administrator was proposed to occur
within 45 days. After the initial 3-year period or once an SAZ (now
called CMZ) has been determined to be violating any PM_2.5
NAAQS, then changes to a MPA would require public review and
notification to ensure that the appropriate monitoring locations and
site types are included.
Several commenters addressed the requirements for the Annual State
Monitoring Report. Some commenters felt that the 45-day review was too
restrictive and should be extended to 60 days. Other commenters felt
that the annual review requirement was reasonable in the short-term,
but should be reconsidered after 3 years.
In response to these comments, the Agency is extending the Regional
review period to 60 days. After the first 3 years, the required annual
review can be reconsidered and its schedule revised as determined by
the EPA Regional Administrator. As discussed earlier in this preamble,
EPA will entertain suggestions for modifications to the published
monitoring network requirements. States can request exemptions from
specific required elements of the network design (e.g., required number
of core SLAMS sites, other SLAMS sites, sampling frequency, etc.)
through the Annual Monitoring Report.

J. Section 58.30 - NAMS Network Establishment

The preamble to the proposal called for States to submit a NAMS
network description (which is to be derived from the core
PM_2.5 SLAMS) of each State's SLAMS network to the EPA
Administrator (through the appropriate EPA Regional Office) within 6
months of the effective date of the final rule. At the same time, a
State's NAMS PM₁₀ 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 EPA Administrator
(through the appropriate EPA Regional Office). The proposed Sec. 58.34
stated that the NAMS Network completion shall be by 3 years after the
effective date of the final rule. This has not been changed in this
final rule. However, the proposed revisions to this section
inadvertently called for the PM_2.5 network description to be
submitted 3 years after the effective date of promulgation. The final
rule has been changed to read July 1, 1998.

K. Section 58.31 - NAMS Network Description

The term spatial averaging zone was used in the proposed revisions
to this section. In the final rule, this term has been replaced by the
term community monitoring zone (CMZ).

[[Page 38773]]

L. Section 58.34 - NAMS Network Completion

The preamble to the proposal called for changes to the NAMS
PM₁₀ network to be completed by 1 year after the effective
date of the final rule and to the NAMS PM_2.5 network to be
completed by 3 years after the effective date of the final rule. The
proposed rule incorrectly stated 6 months instead of 1 year for the
PM₁₀ network to be completed. The final rule has been
changed to read 1 year after the effective date of these regulations
for PM₁₀ and 3 years after the effective date of these
regulations for PM_2.5.

M. Section 58.35 - NAMS Data Submittal

The proposed revision to this section added PM_2.5 as an
additional indicator of PM to the list of pollutants that must submit
air quality data and associated information to the EPA Administrator as
specified in the AIRS Users Guide. This section is promulgated as proposed.

N. Appendix A - Quality Assurance Requirements for SLAMS

1. Summary of proposal. The proposal addressed the fact that
enhanced QA and QC procedures were required in the areas of sampler
operation, filter handling, data quality assessment, and other
operator-related aspects of the PM_2.5 measurement process.
These enhanced QA/QC procedures were necessary for meeting the data
quality objectives for ambient PM_2.5 monitoring.
Most operational QC aspects were specified in 40 CFR part 58,
Appendix A in general terms. However, for PM_2.5, explicit,
more stringent, requirements were 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. Details concerning these operator-related
procedures were proposed to be published as a new section 2.12 of EPA's
Quality Assurance Handbook for Air Pollution Measurement Systems,
Volume II to assist monitoring personnel in maintaining high standards
of data quality.
Procedures were proposed for assessing the resulting quality of the
monitoring data in 40 CFR part 58, Appendix A. Perhaps the most
significant new data quality assessment requirement proposed for
PM_2.5 monitoring was the requirement that each
PM_2.5 SLAMS monitor was to be audited at least six times per
year. This was the first time a requirement had been proposed to assess
the relative accuracy of the mass concentration measured by a PM SLAMS
monitor. Each of these six audits would have been performed by the
monitoring agency and would have consisted of concurrent operation of a
collocated reference method audit sampler along with the
PM_2.5 SLAMS monitor. The data from these collocated audits
were proposed to have been used by EPA to assess the performance of the
PM_2.5 SLAMS monitor and to identify reporting organizations
or individual sites that had abnormal bias or inadequate precision for
the year.
Other data assessment requirements proposed for PM_2.5
monitoring networks were patterned after the current requirements for
PM₁₀ networks and were intended to supplement the audit
procedure. The proposal required PM_2.5 network monitors to
be subject to precision and accuracy assessments for both manual and
automated methods, using procedures similar or identical to the current
procedures required for PM₁₀ monitoring networks. Results of
the field tests performed by the monitoring agencies (including the
field tests) would have been sent to EPA. EPA then would have carried
out the specified calculations which would have become part of the
annual assessment of the quality of the monitoring data.
Although the proposed QA requirements for PM_2.5 would
have resulted in an increase in quality assessment requirement for PM
monitoring, the additional QA/QC checks would have incurred more cost
to the monitoring agency. Some of the proposed new QA/QC assessment
requirements would have somewhat overlapped the information provided by
other checks, such as the periodic flow rate checks and the use of
collocated samplers in monitoring networks.
A revision to 40 CFR part 58, Appendix A, was also proposed to
provide for technical system audits to be performed by EPA at least
every 3 years rather than every year. This change to a less frequent
system audit schedule recognized the fact that for many well
established agencies, an extensive system audit and rigorous inspection
may not have been necessary every year. The determination of the extent
and frequency of system audits at an even lower frequency than the
proposed 3-year interval was being left up to the discretion of the
appropriate EPA Regional Office, based on an evaluation of the Agency's
data quality measures. This change would have afforded both EPA and the
air monitoring agencies flexibility to manage their air monitoring
resources to better address the most critical data quality issues.
2. The PM_2.5 QA system. Based upon public comments, the
Agency has reviewed 40 CFR part 58, Appendix A and re-evaluated several
aspects of the QA and QC quality control system used to assess the
particulate monitoring data. The requirements associated with the
PM₁₀ QA system remained unchanged by these modifications.
Specifically for PM_2.5, the major modifications include
focusing 80 percent of the QA resources to sites with concentrations of
greater than or equal to 90 percent of the annual PM_2.5
NAAQS (or 24-hour NAAQS if that is affecting the area), increasing the
amount of collocated monitors to 25 percent of the total number of
SLAMS monitors within a reporting organization, and changing the FRM
audit procedures to an independent assessment of the bias of the
PM_2.5 monitoring network. The FRM audits were reduced in
number to 25 percent of the SLAMS monitors at a frequency of 4 times
per year. All modifications are discussed in detail in the following
paragraphs.
In response to comments that the proposed QA requirements were
inadequate, and in order to clarify the intent of the quality system,
EPA is incorporating the concept and definition of a quality system
into section 2, Quality System Requirements. EPA defines QA as an
integrated system of management activities involving planning,
implementation, assessment, reporting, and quality improvement to
ensure that a process, item, or service is of the type and quality
needed and expected by the customer. QC is defined as the overall
system of technical activities that measures the attributes and
performance of a process, item, or service against defined standards to
verify that they meet the stated requirements established by the
customer. A quality system is defined as a structured and documented
management system describing the policies, objectives, principles,
organizational authority, responsibilities, accountability, and
implementation plan of an organization for ensuring quality in its work
processes, products (items), and services. The quality system provides
the framework for planning, implementing, and assessing work performed
by the organization and for carrying out required QA and QC.
The Agency used the data quality objective (DQO) process to
specifically develop the QA system for the new PM_2.5
program. The DQO process is a systematic strategic planning tool based

[[Page 38774]]

on the scientific method that identifies and defines the type, quality,
and quantity of data needed to satisfy a specific use. Meeting the new
data quality objectives for ambient PM_2.5 monitoring
requires a combination of QA and QC procedures to evaluate and control
data measurement uncertainty. For this reason, EPA has developed a
quality system specifically for PM_2.5 which incorporates
procedures to quantify total measurement uncertainty, as it relates to
total precision and total bias, within the PM_2.5 monitoring
network. In order to clarify the tools used in the QA system, the
Agency has included definitions in 40 CFR part 58, Appendix A. Total
bias is defined as the systematic or persistent distortion of a
measurement process which causes errors in one direction (i.e., the
expected sample measurement is different from the sample's true value).
Total precision is defined as a measure of mutual agreement among
individual measurements of the same property, usually under prescribed
similar conditions, expressed generally in terms of the standard
deviation. Accuracy is defined as the degree of agreement between an
observed value and an accepted reference value, accuracy includes a
combination of random error (precision) and systematic error (bias)
components which are due to sampling and analytical operations. The
Agency will use various QA tools to quantify this measurement
uncertainty; this includes collocation of monitors at various
PM_2.5 sites, use of operational flow checks, and
implementation of an independent FRM audit.
The measurement system represents the entire data collection
activity. This activity includes the initial equilibration, weighing,
and transportation of the filters to the sampler; calibration,
maintenance, and proper operation of the instrument; handling/placement
of the filters; proper operation of the instrument (sample collection);
removal/handling/transportation of the filter from the sampler to the
laboratory; weighing, storage, and archival of the sampled filter; and
finally, data analysis and reporting. Additional or supplemental
detailed quality assurance procedures and guidance for all operator-
related aspects of the PM_2.5 monitoring process will be
published as a new section 2.12 of EPA's Quality Assurance Handbook for
Air Pollution Measurement Systems, Volume II, Ambient Air Specific
Methods to assist monitoring personnel in maintaining high standards of
data quality.
To clarify the requirements and guidance concerning the SLAMS
ambient air network, the Agency has developed Quality Assurance
Division (QAD) requirements documents, which are referenced in section
2.2. For simplification, the Agency has removed the list of pertinent
operational procedures from this section and has replaced the list with
the updated reference. In response to comments about potential
difficulties in following the requirements in ANSI E-4, EPA has instead
required quality assurance and control programs to follow the
requirements for quality assurance project plans contained in EPA
requirements for quality assurance project plans for environmental data
operations, EPA QA/R-5 an EPA QAD document.
EPA received many comments on the proposed bimonthly audits for
each PM_2.5 site as proposed in section 6.0 of Appendix A.
Commenters expressed concerns about the excessive burden the
requirement would put on State and local air pollution control
agencies, the length of time involved with the process, and the quality
control, reliability, and logistical aspects of a portable audit device.
Based upon these comments, the Agency re-assessed its position
concerning the number of sites and the frequency of audits that the
State and local agencies perform. The Agency feels that independent FRM
audits are essential to reaching the goal of the data quality
objectives for PM_2.5 because these audits evaluate the total
bias for each designated PM_2.5 Federal Reference and
Equivalent monitoring method within the monitoring network. Therefore,
the Agency has modified the proposed audit program to make it
independent and also to reduce the burden on State and local agencies.
Section 6.0 as proposed has been deleted, with remaining data quality
assessment requirements for PM_2.5 included in section 3.5 of
40 CFR part 58, Appendix A. The resulting data will be assessed at
three distinct levels--single monitor level, reporting organization
level, and at a national level. Details of the assessment process will
be published in EPA's Quality Assurance Handbook for Air Pollution
Measurement Systems, Volume II, Ambient Air Specific Methods.
Commenters endorsed the reduction in the frequency of systems
audits from every year to every 3 years as proposed in section 2.5.
Therefore, the requirement for a 3-year schedule for system audits
remains unchanged.
3. Evaluation of measurement uncertainty. EPA received several
comments on the procedures used to address the quality assurance of the
data as proposed in section 3 of the Appendix. Commenters were
concerned about the limited resources available to properly comply with
all aspects of the proposed quality system. In the initial deployment
of the SLAMS PM_2.5 network, special QA emphasis should be
placed on those sites likely to be involved in possible nonattainment
decisions. Once the initial attainment/nonattainment designations have
been made, the Agency recommends focusing 80 percent of the QA activity
(collocated monitors and FRM audits) at sites with concentrations
greater than or equal to 90 percent of the mean annual PM_2.5
NAAQS (or 24-hour NAAQS if that is affecting the area); this percentage
will be 100 percent if all sites have concentrations above either
NAAQS. The remaining 20 percent of the QA activity would be at sites
with concentrations less than 90 percent of the PM_2.5 NAAQS.
If an organization has no sites at concentration ranges greater than or
equal to 90 percent of the PM_2.5 NAAQS, the Agency
recommends 60 percent of the QA activity be at sites among the highest
25 percent for all PM_2.5 sites in the network. The Agency
understands the initial selection of sites will likely be subjective
and based upon the experience of State and local organizations.
Other data assessment requirements for PM_2.5 monitoring
networks are patterned after the current requirements for
PM₁₀ networks and are intended to quantify the monitoring
network's total precision and bias. PM_2.5 network monitors
will be subject to performance assessments for both manual and
automated methods, using procedures similar or identical to the current
procedures required for PM₁₀ monitoring networks. The Agency
received several comments describing incentives for acceptable
performance in the QA field. In response to these concerns, EPA intends
to reduce the QA burden in accordance with network monitoring and
acceptable performance of the QA program. Based upon EPA's yearly data
quality assessment, acceptable performance could result in a reduction
in the frequencies of QA/QC requirements. Additional details for the
incentive program will be provided in the Quality Assurance Handbook
for Air Pollution Measurement Systems, Volume II, Ambient Air Specific
Methods.
The Agency believes that to develop a national, consistent
monitoring network with quantifiable data quality, a quality system
must be developed that permits maximum flexibility yet ensures that the
measurement uncertainty is known and under control. For this

[[Page 38775]]

reason, the Agency has removed the requirement in section 3.3.5 that
the paired monitors have the same FRM or equivalent sampler designation
number, but now formalizes the 6-day sampling schedule for collocated
monitors into the regulation; this was previously described in
guidance.
With regard to the requirements for evaluating measurement
uncertainty, the estimates of bias within the monitoring network will
be evaluated with flow audits (section 3.5.1) and independent FRM
audits (see comments concerning section 3.5.3). An audit of the
operational flow rate determines bias as performed by the local
operators of manual methods for PM_2.5 with each sampler each
calendar quarter. Using a flow rate transfer standard, each sampler
will be audited at its normal operating flow rate. The percent
differences between the standard and sampler flow rates will be used to
evaluate instrument-specific bias.
Specifically, for Federal Reference and Equivalent automated
methods, an additional assessment of the precision will consist of a
one-point precision check performed at least once every 2 weeks on each
automated analyzer used to measure PM_2.5. This precision
check is performed by checking the operational flow rate of the
analyzer, using a procedure similar to that currently used for
PM₁₀ network assessments. In addition, an alternative
procedure may be used where, under certain specific conditions, 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. This alternative procedure is also made applicable
to PM₁₀ methods.
With regard to the proposed requirements in section 3.5.2,
(Measurement of precision using collocated procedures for automated and
manual methods of PM_2.5) several commenters felt that
invalid data or data of questionable quality should not be a part of
the data base, since the general public and many end-users of the data
such as consultants and modelers do not always make distinctions about
data. Data reporting requirements specify that all valid monitoring
data be reported to AIRS. EPA believes that the requirement contained
in section 4.1 to report all QA/QC measurements including results from
invalid tests is necessary to fully assess the performance of reporting
organizations and to allow EPA to recommend appropriate corrective
actions. Such data will be flagged so that it will not be utilized for
quantitative assessments of precision, bias, and accuracy. EPA also
received many comments on the use of collocated samplers to assess
precision. Most of these comments advocated an increase in the number
of collocated monitors as an alternative to reduce the burden of the
independent audit system. Based upon these comments, EPA has reassessed
its position on the number of collocated monitors and now requires 25
percent of the total number of monitors for each designated Federal
Rand Equivalent Method within a reporting organization to be
collocated. To further assess the total precision and bias of the
monitoring network, half of the collocated monitors for each designated
Federal Reference and Equivalent Method must be collocated with a
Federal Reference Method (FRM) designated monitor and half must be
collocated with a monitor of the same designated method type as the
primary monitor. An example is shown in Table A-2 in 40 CFR part 58,
Appendix A.
The Agency received numerous comments concerning the burden of the
proposed FRM audit procedures for PM_2.5 (section 3.5.3),
which consisted of having every site audited six times each year with a
portable FRM audit sampler. In response to these comments, EPA has
reduced the number of audits to 25 percent of the total number of SLAMS
PM_2.5 sites to be audited 4 times each year. In addition,
EPA has reduced the burden of the State and local agencies
responsibility for implementing the audits by providing access to the
existing EPA National Performance Audit Program (NPAP) or other
comparable programs. The details concerning the assessment of the
resulting data will be published in EPA's Quality Assurance Handbook
for Air Pollution Measurement Systems, Volume II, Ambient Air Specific
Methods.
4. Reporting requirements. EPA received several comments concerning
the adequacy of QA reporting requirements (section 4). The Agency has
addressed these comments by strongly encouraging earlier QA data
submittal in order to assist the State and local agencies in
controlling and evaluating the quality of the ambient air SLAMS data.
5. Data quality assessment. In response to several comments
concerning the adequacy of the QA data assessment procedures for the
PM_2.5 program, including parts of proposed section 6.0, EPA
developed a new section 5.5 to consolidate and simplify the procedures
and calculations for the precision, accuracy, and bias measurements
used to quantify PM_2.5 data quality. The quality assurance
system has been nested in such a manner that will allow for the
assessment of total measurement bias and precision, as well as portions
of the measurement system (i.e. field operations, laboratory
operations, etc.). Four distinct quality control checks and audits are
implemented to evaluate total measurement uncertainty: (1) Determine
instrument accuracy and instrument bias from flow rate audits, (2)
determine precision from collocated monitors where the duplicate
monitor has the same method designation, (3) determine a portion of the
measurement bias from collocated monitors where the duplicate sampler
is an FRM device, and (4) determine total measurement bias from FRM
audits. This design will allow for early identification of data quality
issues in the measurement phases (field/laboratory operations) where
they may be occurring and therefore, effective implementation of
corrective actions.
6. FRM audit requirements. The Agency received many comments
concerned with the burden the proposed FRM audit system (the deleted
Section 6: Annual Operational Evaluation of PM_2.5 Methods)
would put upon the individual State and local air pollution agencies.
Based upon the numerous comments, the Agency has re-assessed its
position concerning the audit system. The Agency reduced this burden by
providing the State and local agencies the flexibility to access the
existing NPAP program or comparable program, additionally reducing the
burden to 25 percent of the total number of SLAMS PM_2.5
sites each year, and reducing the frequency of the audits to 4 per
year. EPA has removed section 6.0 from the regulations and incorporated
the appropriate information into other sections within 40 CFR part 58,
Appendix A. Additional information will be provided in the Quality
Assurance Handbook for Air Pollution Measurement Systems, Volume II,
Ambient Air Specific Methods.

O. Appendix C - Ambient Air Quality Monitoring Methodology

EPA proposed that 40 CFR part 53, subpart C, be amended to allow
the use of certain PM₁₀ monitors as surrogates for
PM_2.5 monitors for purposes of demonstrating compliance with
the NAAQS. The proposal further stated however, following the
measurement of a PM₁₀ concentration higher than the 24-hour
PM_2.5 standard or an annual average concentration higher
than the annual average PM_2.5 standard, the PM₁₀
monitor would have to be replaced with a PM_2.5 monitor. In
the proposal of Appendix C, EPA also discussed the use of several types
of PM_2.5 samplers at a SLAMS that are not designated as a

[[Page 38776]]

reference or equivalent method under 40 CFR part 53. First, EPA
proposed the use of certain nonreference/nonequivalent PM_2.5
methods that could 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_2.5,
as specified of 40 CFR part 53, subpart C 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 the proposed Appendix
A to 40 CFR part 53, at twice the normal evaluation interval. A method
that meets these proposed requirements would not become an equivalent
method, but the method could be used at that particular SLAMS site for
any regulatory purpose. Second, EPA discussed the use of CAC methods
described in Sec. 58.13(f) which are intended to supplement a reference
or equivalent manual method at certain SLAMS, so that the manual method
could reduce its sampling frequency from every day to once in 3 days.
In addition, the proposed Appendix C clarifies that the monitoring data
obtained with CAC methods would be restricted to use for the purposes
of the proposed Sec. 58.13(f) and would not be used for making
comparisons to the NAAQS. Finally, the proposal also described samplers
for fine particulate matter used in the IMPROVE network (hereafter
termed IMPROVED samplers) and clarified that IMPROVE samplers, although
not designated as equivalent methods, could be used in SLAMS for
monitoring regional background concentrations of fine particulate
matter.
Some commenters questioned the proposed use of PM₁₀
samplers as substitutes for PM_2.5 samplers to satisfy
requirements for PM_2.5 SLAMS monitoring. EPA reassessed the
logic behind this proposal and agreed with commenters that substitute
samplers should not be allowed. In order for a PM₁₀ sampler
to be a substitute PM_2.5 sampler, the annual average
PM₁₀ would have to be less than 15 <greek-m>g/m3
and the annual maximum 24-hour PM₁₀ would have to be less
than 65 <greek-m>g/m3. This situation would not be
representative of community-oriented monitoring, would only exist at a
few rural locations and would not even provide useful information about
PM_2.5 background concentrations; therefore EPA has deleted
this provision from Appendix C.
Appendix C is being amended to add a new section 2.4 continuing
provisions that allow the use of a PM_2.5 method that had not
been designated as a reference or equivalent method under 40 CFR part
53 at a SLAMS under special conditions. Such a method will be allowed
to be used at a particular SLAMS site to make comparisons to the NAAQS
if it meets the basic requirements of the test for comparability to a
reference method sampler for PM_2.5, as specified in 40 CFR
part 53, subpart C, 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 will
then be further subjected to the operating precision and accuracy
requirements specified in 40 CFR part 53, Appendix A, at twice the
normal evaluation interval. A method that meets these requirements will
not become an equivalent method, but can be used at that particular
SLAMS site for any regulatory purpose. The method will be assigned a
special method code, and data obtained with the method will be accepted
into AIRS as if they had been obtained with a reference or equivalent
method. This provision will allow the use of non-conventional
PM_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 40 CFR part 53.
In addition, Appendix C is being amended to add a new section 2.5
to clarify that CAC methods for PM_2.5 approved for use in a
SLAMS under new provisions in Sec. 58.13(f) will not become de facto
equivalent methods as proposed. This applies to methods that have not
been designated equivalent or do not satisfy the requirements of
section 2.4 previously described. In response to recommendations that
IMPROVE samplers be allowed for use at core background and core
transport sites, EPA is revising section 2.9 to define 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 and regional transport concentrations of
fine particulate matter.
Finally, minor changes are being made 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.

P. Appendix D - Network Design For State and Local Air Monitoring
Stations (SLAMS), National Air Monitoring Stations (NAMS) and
Photochemical Assessment Monitoring Stations (PAMS)

1. Section 2.8.1 - Specific design criteria for PM_2.5.
The proposed regulation contained language regarding the implementation
of spatial averaging through the design of PM_2.5 monitoring
networks. MPAs and SAZs were introduced to conform to the population-
oriented, spatial averaging approach taken in the proposed
PM_2.5 NAAQS under 40 CFR part 50. While this proposed
approach is more directly related to the epidemiological studies used
as the basis for the proposed revisions to the particulate matter
NAAQS, it recognized that the use of MPAs and SAZs introduced greater
complexity into the network design process and the comparison of
observed values to the level of the PM_2.5 annual NAAQS.
A great number of comments were received concerning the
communication and complexity of spatial averaging, the selection of
monitors, and the need for providing flexibility in specifying network
designs and spatial averaging given that the nature and sources of fine
particles vary from one area to another.
In response to concerns about the implementation and communication
of spatial averaging, EPA is clarifying the requirement for SAZs by
changing some terminology. EPA is also making it clear that the annual
mean PM_2.5 from a single properly sited monitor that is
representative of community-wide exposures or an average of annual mean
PM_2.5 concentrations produced by one or more of such
monitors that meet siting requirements and other constraints as set
forth in this rulemaking can be compared to the PM_2.5 annual
standard. Specifically, this rule indicates that comparisons to the
annual PM_2.5 standard can be made through the use of
individual monitors or the annual average of monitors in specific CMZs.
Community-oriented monitors should be used for these comparisons. This
approach will provide State and local agencies with additional
flexibility in defining community-wide air quality and in designing
monitoring networks. The annual average PM_2.5 concentration
from one or more monitoring sites within a CMZ may be averaged to
produce an alternative indicator of annual average community-wide air
quality. However, the criteria for establishing CMZs have been modified
(compared to the previous SAZs) so that initial monitors will be
located in those

[[Page 38777]]

areas expected to have the highest community-oriented concentrations.
It should be noted that many of the sites meeting the siting,
monitoring methodology, and other monitoring requirements in 40 CFR
part 58 include population-oriented SPMs and industrial monitors.
The eligible core monitors in a CMZ still must be properly sited
and meet the constraints specified in section 2.8.1.6 of 40 CFR part
58, Appendix D. The term SAZ has been replaced with CMZ and zone
throughout Appendix D. If the State chooses to make comparisons to the
annual PM_2.5 NAAQS directly with individual monitors that
use the siting requirements of section 2.8.1.6.3 of 40 CFR part 58,
Appendix D then it is not required to perform the analyses needed to
establish a CMZ. A State still would be expected to justify that the
site meets the specified siting requirements and is representative of
community-wide exposures. Then it would not be expected, apriori, to
define the boundaries of zones within which the monitoring data would
be averaged. This section, that was proposed as ``Monitoring Planning
Areas and Spatial Averaging Zones,'' has been retitled as ``Specific
Design Criteria for PM_2.5.''
2. Section 2.8.1.3 - Core monitoring stations for PM_2.5.
The proposed regulations described requirements for the numbers of
SLAMS sites including core SLAMS. To provide a minimal PM_2.5
network in all high population areas for protection of the annual and
24-hour PM NAAQS, each required MPA was proposed to have at least two
core monitors. The new core monitoring locations would be an important
part of the basic PM-fine SLAMS regulatory network. These sites are
intended to primarily reflect community-wide air pollution in
residential areas or where people spend a substantial part of the day.
In addition to the population-oriented monitoring sites, core monitors
would also be established for regional background and regional
transport monitoring.
To permit interface with measurements of ozone precursors and
related emission sources that may contribute to PM_2.5, an
additional core monitor collocated at a PAMS site was proposed to be
required in those MSAs where both PAMS and PM_2.5 monitoring
are required. The core monitor to be collocated at a PAMS site would be
considered to be part of the MPA PM_2.5 SLAMS network and
would not be considered to be a part of the PAMS network as described
in section 4 of 40 CFR part 58, Appendix D. Each SAZ in a required MPA
was proposed to have at least one core monitor; SAZs in optional MPAs
were proposed to have at least one core monitor; and SAZs were proposed
to have at least one core site for every four SLAMS.
Several commenters addressed issues related to the number of core
SLAMS, population-oriented SLAMS, and other SLAMS. Numerous commenters
supported increasing the number of stations while few supported
decreasing the number of stations. In addition, some commenters
addressing the issue of spatial averaging also suggested that more
monitors might be needed to address less populated areas and areas near
hot spots. A few commenters suggested that large States or geographic
areas might require several regional background or regional transport
sites and that increased monitoring in rural or remote areas would be
needed to establish naturally occurring concentrations produced by
biogenic sources.
EPA agrees with commenters that more monitors are needed to address
smaller communities, larger MSAs with several source categories of fine
particulate emissions, to address coverage for multiple sites in
optional CMZs, regional transport monitoring upwind of the major
population centers in the country, and additional sites near
population-oriented pollution hot spots. Accordingly, EPA has revised
the regulation to increase the number of required core SLAMS and other
SLAMS. These changes result in approximately 220 more required sampling
sites, nationally, as compared to the number proposed (850 versus 629).
At least one core SLAMS is now required in any MSA with a population
greater than 200,000. EPA is requiring additional sites in all MSAs
with population greater than 1 million in accordance with the following
table:

Table 1.--Required Number of Core SLAMS According to MSA Population
------------------------------------------------------------------------
Minimum Required No. of Core
MSA Population Sitesa
------------------------------------------------------------------------
>1 M 3
------------------------------------------------------------------------
>2 M 4
------------------------------------------------------------------------
>4 M 6
------------------------------------------------------------------------
>6 M 8
------------------------------------------------------------------------
>8 M 10
------------------------------------------------------------------------
aCore SLAMS at PAMS are in addition to these numbers.

This section, which was proposed as section 2.8.2.1, has been
renumbered as section 2.8.1.3.
As discussed in Sec. 58.13, Operating Schedule, all
PM_2.5 SLAMS are required to have a minimum operating
schedule of once every 3 days, except for a subset of at least two core
PM_2.5 sites per MSA with population greater than 500,000 and
one site in each PAMS area that is required to conduct daily sampling
as proposed.
3. Section 2.8.1.4 - Other PM_2.5 SLAMS locations. EPA is
retaining the requirement to have a minimum of one regional background
and one regional transport site per State and recognizing the need for
exceptions when appropriate, particularly in small States; however,
these sites are no longer designated as core SLAMS. EPA also is
requiring additional SLAMS monitors based upon the State population
less the population in all required MSA monitoring areas (i.e., MSAs
greater than 200,000), to provide population coverage throughout the
State, particularly in States with fewer urbanized areas. For this
remaining population there should be one additional SLAMS per 200,000
population. These additional sites may be used to satisfy any SLAMS
objective anywhere in the State including population areas (large
cities or small towns) or regional transport in rural areas. The
requirement for the additional SLAMS is over and above the requirement
for one regional background and regional transport site per State as
mentioned above. This section, which was proposed as section 2.8.2.2,
has been renumbered as section 2.8.1.4. For planning purposes, EPA
expects that the total number of sites in a mature, fully-developed
PM_2.5 network will exceed these required minimums. The
projected total number is 1,500 sites, as compared to the proposed
1,200 sites. This is an increase of 25 percent compared to the number
proposed and is based on the recognized need for more monitoring in
smaller communities, more monitors in larger MSAs with several source
categories of fine particulate emissions, the possible need for
multiple sites in optional CMZs, the need to support regional transport
monitoring upwind of the major population centers in the country, and
the need for additional sites near pollution hot spots.
4. Section 2.8.1.5 - Additional PM_2.5 Analysis
Requirements. EPA recognizes the need for chemical speciation of
particulate matter. Such data are needed to characterize
PM_2.5 composition and to better understand the sources and
processes leading to elevated PM_2.5 concentrations. Because
of the costs associated with conducting filter analysis on a routine
basis, however the

[[Page 38778]]

proposal only required filters to be archived so they would be
available for subsequent chemical analysis on an as needed basis. EPA
recognizes that there is a need for speciation and other specialized
monitoring efforts that were not specifically required by the proposed
rule. Accordingly, EPA intended to give these PM monitoring efforts
high priority in its section 105 grants program.
Many commenters supported the concept of chemical speciation,
noting that speciation was essential for identifying all of the
components of fine particles and developing control strategies. Some
commenters recommended that the program be conducted under national or
regional supervision to ensure consistency and reduce costs, and that
routine chemical analyses are conducted in a centralized laboratory.
EPA also received several comments on the proposed archival
requirements. Some commenters suggested that if chemical speciation was
required, the filter archival requirement could be eliminated. Other
commenters noted that the long-term archival requirements placed
additional resource burdens on agencies, and that possible filter
degradation and/or bias could result from archiving samples prior to
analysis.
Based on these comments, the Agency reassessed its position
concerning chemical speciation as an optional part of the
PM_2.5 monitoring program. Although speciation is resource
intensive, EPA believes that its overall value in satisfying control
strategy and other data needs justifies the added expense. Chemical
speciation is critically important for the implementation efforts
associated with air quality programs. Specific subject areas supported
by chemical speciation include source attribution analysis (i.e.,
determining the likely mix of sources impacting a site) and emission
inventory and air quality model evaluation. Emission inventory and
modeling tools are used to develop sound emission reduction strategies.
Speciated data are especially critical for air quality model evaluation
since resolved chemical measurements provide greater assurance that
acceptable model behavior results from appropriate process
characterization rather than through the collective effect of
compensating errors. Speciated data provide greater ability to identify
the causes of poor model performance and implement corrective actions.
After strategies are developed and controls are implemented, chemically
resolved PM_2.5 data provide a tracking and feedback
mechanism to assess the effectiveness of controls and, if necessary,
provide a basis for adjustment. Chemical speciation provides an
additional quality check on data consistency since a basis for
comparing the sum of individual components (i.e., speciated data) with
total mass measurement is available. Also, speciated data supports the
forthcoming regional haze program by providing a basis for developing
reliable estimates of seasonal and annual average visibility
conditions. Chemically resolved data should provide more complete data
for future health studies. EPA believes that speciation should be part
of the final PM_2.5 monitoring program due to the collective
value of speciation. However, the Agency also believes that flexibility
must be provided to the States to tailor efforts to the needs of
specific areas. Based on public comments, a minimum chemical speciation
trends network will be required to address the needs discussed above.
Based on this requirement to collect speciated data at NAMS sites,
EPA is eliminating the requirement to archive filters from NAMS.
However, all other SLAMS sites will still be required to archive
filters for a minimum of 1 year after collection. Access to these
archived filters for chemical speciation would be helpful in cases
where: (1) Exceedances or near exceedances of the standard have
occurred and additional information and data are needed to determine
more precisely possible sources contributing to the exceedances or high
concentrations, and (2) certain sites may have shown marked differences
in air quality trends at the local or national level for no apparent
reason and analysis of filters from more than one site might be
required to determine the reason(s) for the differences. EPA intends to
assign a high priority to this program through its section 105 grant
allocation program and will issue guidance describing the monitoring
methods and scenarios under which speciation should be performed. The
FRM described in 40 CFR part 50, Appendix L, is finalized as a single-
filter based method. Therefore, supplementary monitoring equipment
that, for example, permits the use of additional filter media will be
needed to perform the appropriate speciation. Additional details on the
monitoring methodology for performing speciation and related
information on filter handling and/or storage will be addressed in
forthcoming EPA guidance.
EPA is now instructing the States to initiate chemical speciation
in accordance with forthcoming EPA guidance at PM_2.5 core
sites collocated at approximately 25 PAMS sites and at approximately 25
other core sites for a total of approximately 50 sites nationwide.
These sites would be selected as candidates for future NAMS
designation. Depending on available resources, chemical speciation
could be expanded to additional sites in the second and third years.
The requirement to collect speciated data will be reexamined after 5
years of data collection. Based on this review, the EPA Administrator
may exempt some sites from collecting speciated data. At a minimum,
chemical speciation will include analysis for metals and other
elemental constituents, selected anions and cations, and carbon.
EPA recognizes that advantages related to consistency, quality
assurance and scales of economy would result from using centralized
laboratories for conducting chemical analyses. However, EPA is
concerned about the available laboratory capacity for meeting the needs
of a national PM_2.5 speciation network. Several options are
under consideration that include developing new central and regional
laboratories and exploring the use of existing federal and State
facilities. This section, which was proposed as section 2.8.2.4, has
been renumbered as section 2.8.1.5.
5. Section 3.7.6 - NAMS speciation. Consistent with the previous
discussion on speciation, the requirement to establish a subset of
approximately 50 NAMS sites for routine speciation is described in a
new section 3.7.6 of 40 CFR part 58, Appendix D. The approximately 50
sites will include the ones collocated at PAMS and approximately 25
other sites to be selected by the EPA Administrator, in consultation
with the Regional Administrators and the States. After 5 years of data
collection, the EPA Administrator may exempt some sites from collecting
speciated data. The number of NAMS sites at which speciation will be
performed each year and the number of samples per year will be
determined in accordance with EPA guidance. The subsequent sections of
section 3.7 have been renumbered accordingly.

Q. Appendix E - Probe and Monitoring Path Siting Criteria for Ambient
Air Quality Monitoring

The proposed revisions to this Appendix consisted of relatively
minor changes in the siting criteria to expand the requirements to
include PM_2.5. Minor changes were made to the example
monitoring location in section 8.1 of the proposed revisions to 40 CFR
part 58, Appendix E, to replace ``mid-

[[Page 38779]]

town Manhattan in New York City'' with ``central business district of
a Metropolitan area.''

R. Appendix F - Annual Summary Statistics

A new section was proposed to be added to 40 CFR part 58, Appendix
F, to include annual summary statistics for PM_2.5. No
changes were made to the proposed revisions.

S. Review of Network Design and Siting Requirements for PM

1. PM₁₀. The network design and siting requirements for
the annual and 24-hour PM₁₀ NAAQS will continue to emphasize
identification of locations at maximum concentrations. The
PM₁₀ network itself, however, will be revised because the
new PM_2.5 standards will likely be the controlling standards
in most situations.
The new network for PM₁₀ will be derived from the
existing network of SLAMS, NAMS, and other monitors generically
classified as SPMs which include industrial and special study monitors.
Population-oriented PM₁₀ NAMS will generally be maintained
as will other key sampling locations in existing nonattainment areas,
and in areas whose concentrations are near the levels of the revised
PM₁₀ NAAQS. Currently approved reference or equivalent
PM₁₀ samplers can continue to be utilized. The revised
network will ensure that analysis of national trends in PM₁₀
can be continued, that air surveillance in areas with established PM
emission control programs can be maintained, and that the
PM₁₀ NAAQS will not be jeopardized by additional growth in
PM₁₀ emissions. PM₁₀ sites should be collocated
with new PM_2.5 sites at key community-oriented monitoring
stations so that better definition of fine and coarse contributions to
PM₁₀ can be determined to provide a better understanding of
exposure, emission controls, and atmospheric processes. PM₁₀
sites not needed for trends or with maximum concentrations less than 60
percent of the NAAQS should be discontinued in a longer-term
PM₁₀ network.2 The sampling frequency at all
PM₁₀ sites can be changed to a minimum of once in 3 days,
which will be sufficient to make comparisons with the new
PM₁₀ standards at most locations. Locations without high 24-
hour concentrations of PM₁₀ (e.g., 140 <greek-m>g/
m3) may be exempted from this provision, and their sampling
frequency reduced to a minimum of once in 6 days.
---------------------------------------------------------------------------

2Memorandum from William F. Hunt, Jr., Director, Emissions,
Monitoring, and Analysis Division dated April 22, 1997, to EPA
Regional Directors entitled Ambient Monitoring Reengineering (found
in Docket A-96-51).
---------------------------------------------------------------------------

2. PM_2.5. Consistency with the new PM_2.5
NAAQS demands the adoption of new perspectives for identifying and
establishing monitoring stations for the PM_2.5 ambient air
monitoring network. First, sites which are representative of community-
wide air quality shall be the principal focus of the new
PM_2.5 monitoring program; however, all eligible population-
oriented PM_2.5 sites (including regional background and
regional transport sites) will be used for comparisons to the new
NAAQS. Second, eligible SLAMS and other eligible SPMs may be averaged
within properly defined CMZs to better characterize exposure and air
quality for comparison to the annual PM_2.5 NAAQS. Third,
population-oriented PM_2.5 SLAMS and SPMs representative of
unique microscale or middle scale impact sites would not be eligible
for comparison to the annual PM_2.5 NAAQS and would only be
compared to the 24-hour PM_2.5 NAAQS. The 24-hour
PM_2.5 NAAQS is intended to supplement the annual
PM_2.5 standard by providing additional protection at these
small spatial scales. A violation of the annual PM_2.5 NAAQS
at localized hot spot and other areas of a small spatial scale (i.e.,
less than 0.5km in diameter) are not reflective of the data used to
establish the annual PM_2.5 NAAQS. It is also not indicative
of a greater area-wide problem which would initiate the need for an
area-wide implementation strategy. Clearly, the combination of careful
network design, i.e., one that identifies the differences in monitor
locations, and an implementation policy that strives to develop
effective strategies optimizing regional and local efforts is required
to address the intent of the PM_2.5 NAAQS.
The new network for PM_2.5 consists of a core network of
community-oriented SLAMS monitors (including certain SLAMS collocated
at PAMS), other SLAMS monitors (including background and regional
transport sites), a NAMS network for long-term monitoring for trends
purposes, and a supplementary network of SPMs. Daily sampling is
required at a subset of core SLAMS located in MSAs with population
greater than 500,000 and at core SLAMS collocated at PAMS sites. This
will provide more accurate and complete information on population
exposure. One in 3-day sampling is required at NAMS and at all other
SLAMS, except when exempted by the Regional Administrator, in which
case one in 6-day sampling is required. Frequent measurements are
important to characterize the day-to-day variability in
PM_2.5 concentrations, and to understand episodic behavior of
PM_2.5. Routine chemical speciation of PM_2.5 will
be required for a small subset of the core SLAMS. This is necessary to
establish and track effective emission control strategies to assure
protection of the NAAQS. These sites shall be part of the future
PM_2.5 NAMS network. Overall, many of the new
PM_2.5 sites are expected to be located at existing
PM₁₀ sites, that are representative of monitoring oriented
exposures and would be collocated with some PAMS sites.
The concepts that address the intent of PM_2.5 network
for making comparisons to the NAAQS are embodied through: (1)
Monitoring planning areas; (2) specially coded sites including
community-oriented (core) SLAMS, regional transport and regional
background SLAMS, and other SLAMS or SPMs whose data would be used to
compare to the levels of the annual and 24-hour PM_2.5 NAAQS;
(3) SLAMS or SPMs representative of unique population-oriented
microscale or middle scale locations that are only eligible for
comparison to the 24-hour PM_2.5 NAAQS, and (4) individual
community-oriented sites or CMZs to correspond to the spatial averaging
approach defined by the annual PM_2.5 NAAQS.
Core sites are community-representative monitoring sites which are
among the most important SLAMS for identifying areas that are in
violation of the PM_2.5 NAAQS and to be used for the
associated SIP planning process. Because of their generally larger
spatial scales of representativeness, the core sites are the sites most
likely to be eligible for spatial averaging and are also vital in order
to establish the boundaries of potential areas of violation of the
NAAQS that would be reflective of the areas of highest population
exposure to fine particles. Core sites are neighborhood scale in their
spatial dimensions. Core SLAMS and specific SPM monitoring locations
which are eligible for spatial averaging must be identified in the PM
monitoring network description, satisfy criteria outlined in Appendix
D, and be approved by EPA. In accordance with information to be
specified by the AIRS guidance, the State shall assign the appropriate
monitoring site code when reporting these data to EPA.
Regional transport and regional background sites are located
outside major metropolitan areas and would generally be upwind of one
or more high concentration PM_2.5 impact areas. These sites
are expected to be in areas

[[Page 38780]]

of relatively low population density or in unpopulated regions. The
collection of data at these sites is encouraged because they are
critical for the complete understanding of potential pollutant
transport and for the development and evaluation of emission control
strategies. Although violations of the NAAQS may be observed at these
sites, the interpretation and use of such data observed at regional
transport and regional background locations will be addressed in the PM
implementation program.
SLAMS monitoring locations generally should reflect the population-
oriented emphasis of the new NAAQS' population risk management approach
and its data would be used for NAAQS comparisons. SPMs, on the other
hand, could represent a variety of monitoring situations, some of which
are not appropriate for comparison to the PM_2.5 standards.
This includes monitoring at non-population-oriented hot spots or
special emissions characterization sites that do not meet EPA siting
criteria or required SLAMS monitoring methodology, but provide valuable
planning information to support the SIP process. In addition, certain
SLAMS and SPMs that represent small spatial scales (i.e., sites that
are classified as microscale or middle scale, in accordance with
Appendix D) would not represent average, community-oriented air
quality. In general, such locations would be relatively close to a
single PM emission source or a collection of small local sources. An
example of such a location is a unique microscale site in a non-
residential part of an urban area and which may be zoned industrial.
Clearly, such a site should not be called a SLAMS. There might also be
SLAMS sites in residential districts which are representative of small
maximum concentration impact areas. Due to the greater spatial
homogeneity of fine particles, the existence of such small scale impact
locations is expected to be much less than that for coarse particles.
When SLAMS or SPMs do represent small, unique population-oriented
impact areas, they should be used for comparison to the 24-hour
PM_2.5 standard but not for the annual standard. This is
especially true when the site is dominated by a single emission source.
In general, these types of small impact sites may be surrounded by
broader areas of more homogeneous concentrations which are reflective
of community-wide air quality. However, if the State chooses to monitor
at a unique population-oriented microscale or middle scale location and
the monitoring station meets all applicable 40 CFR part 58 requirements
(including monitoring methodology), then the data shall be used only
for comparison to the 24-hour PM_2.5 standard. This is
consistent with the underlying rationale of the PM_2.5 NAAQS.
Such monitors would require a special AIRS code when their data are
submitted to EPA, as specified by AIRS guidance.
Exceptions to the use of micro and middle scale PM_2.5
for comparison only to the 24-hour standard may exist when micro or
middle scale PM_2.5 sites represent several small areas in
the monitoring domain which collectively identify a larger region of
localized high concentration. For example, there may be two or more
disjoint middle scale impact areas in a single residential district
that are not predominantly influenced by a single PM_2.5
emission source. In this case, these small scale sites should be used
for comparison to the annual NAAQS. This is because their annual
average ambient air concentrations can be interpreted as if they
collectively represent a larger scale. In a sense, this situation can
be viewed as a neighborhood of small scale impact areas. These concepts
and associated requirements are discussed in section 2.8.1 of 40 CFR
part 58, Appendix D.
The new network design and siting requirements encourage the
placement of PM_2.5 monitors both within and outside of
population centers in order to: (1) Provide air quality data necessary
to facilitate implementation of the PM_2.5 NAAQS, and (2)
augment the existing visibility fine particle monitoring network. The
coordination of these two monitoring objectives will facilitate
implementation of a regional haze program and lead to an integrated
monitoring program for fine particles.
To achieve the appropriate level of air quality surveillance in
such areas, EPA believes it is important to coordinate and integrate
the regional background and regional transport monitoring sites
specified in this final rule with the existing IMPROVE monitors that
have been in place in a number of locations around the country since
the late 1980s to characterize fine particulate 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 forthcoming to support this program.
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 rule, 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_2.5 and visibility monitoring networks in the
most efficient and effective ways to meet the collective goals of these
programs. It is EPA's intent that monitoring conducted for purposes of
the PM_2.5 primary and secondary NAAQS (including regional
background and regional transport sites), and for visibility protection
be undertaken as one coordinated national PM_2.5 monitoring
program, rather than as a number of independent networks.
Although the major emphasis of the new PM_2.5 network 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 analyses are
suggested concerning the location of nephelometers (or other continuous
PM measuring devices) at some core monitoring sites and the collection
of meteorological data at core SLAMS sites (including background and
regional transport sites).

T. Resources and Cost Estimates for New PM Networks

The proposed rules contained a discussion of the costs associated
with the start-up and implementation of a PM_2.5 network and
the phase-down of the existing PM₁₀ network.
1. Resources and costs. Several commenters expressed concern about
the costs of the proposed monitoring and QA/QC requirements. Most
commenters wanted EPA to provide the funds to meet the increased effort
and costs with new monies to the agencies, noting that implementing the
network in a timely manner will depend heavily on timely grant
assistance from EPA.
Numerous commenters expressed concern that either not enough
monitoring money was projected or that the program would be an unfunded
mandate. Commenters felt that EPA should budget the funds necessary to
develop an adequate PM_2.5 network that will support all SIP
obligations, including support for speciation. Funds to implement a new
monitoring network should include one-time funding to

[[Page 38781]]

procure sampling, calibration, laboratory, and audit equipment, plus
annual funding to support field and laboratory operations.
Several commenters felt that EPA estimates were too low, citing
underestimates for additional operational, analytical, and equipment
costs including daily sampling; speciation; startup for new monitoring
locations; laboratory modifications; operator training; travel; data
collection and reporting; greater QA equipment and manpower needs;
field testing of reference and equivalent methods; and continuous
monitors. No commenter felt that EPA estimates were too high.
A few commenters addressed the suggested portions of the total
monitoring program cost for speciation. Several commenters suggested
that the cost of requiring speciation could be reduced by limiting the
requirement to a subset of the daily monitoring sites, or offset by
eliminating the requirement for daily sampling, noting that any cost
savings would be overwhelmed by the greater number of PM_2.5
sites and the number of sites conducting everyday sampling.
EPA understands the complexities and resource demands required by
State and local agencies in establishing and implementing the new
regulations. In its review of the comments on the use of the proposed
Federal reference sampler and associated quality assurance
requirements, the Agency has published more cost-effective requirements
with this final rule for monitoring network design, methodology, and
quality assurance. Likewise, EPA recognizes the subsequent need for it
to provide technical and financial assistance. In this regard, some
control agencies have used FY-97 grant allocations to procure
PM_2.5 prototype instruments or upgrade their filter weighing
facilities. Additionally, the Agency has designated approximately
$10,935,000 in section 105 grant monies for distribution to States in
FY-98. EPA intends to assign a high priority to the PM_2.5
monitoring program through its section 105 grants, and additional grant
dollars have been earmarked by EPA for subsequent years which should
ensure successful implementation of the PM_2.5 monitoring
program.
2. Revised cost analysis. In response to comments on cost
estimation and new requirements described earlier, EPA has revised its
estimates for the projected PM₁₀ and PM_2.5
networks. EPA believes that it has both improved its cost estimates and
more adequately addressed the needs for the PM monitoring program. The
net costs associated with the final PM rules promulgated today include
the start-up and implementation costs associated with the new
PM_2.5 network and the cost savings associated with phase-
down of the existing PM₁₀ network. The estimated costs in
the preamble have been revised to reflect changes to the regulations
based on comments received on the proposed changes in 40 CFR parts 50,
53, and 58. In particular, PM_2.5 network costs have been
revised to reflect an increase in the number of sites to 1,500, newer
cost estimates for prototype samplers, equipping many sites with
sequential samplers to provide for greater operational flexibility,
reducing the number and frequency of audits with federal reference
method samplers, and providing for additional multi-filter sampling to
determine PM_2.5 constituent species. In addition,
PM₁₀ network costs have been revised to reflect an increase
in the remaining number of PM₁₀ sites to 900 and a sampling
frequency of once every 3 days (instead of once every 6 days, as
proposed) for those sites that previously had been sampling everyday,
every 2 days, or every 6 days.
Table 2 shows the PM_2.5 network phase-in data including
number of sites and samplers, costs for capital equipment, sampling and
quality assurance, filter analyses, and special studies. Table 3
provides a breakdown of the costs associated with the filter analyses.
Table 4 provides a breakdown of the phase-down costs for the
PM₁₀ network. The costs are shown for a current network of
approximately 1,650 sites in 1997 and the phase-down to a future
projected network of 900 sites. Table 5 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 requirements. Tables 2 through 5 follow.

Table 2.--PM<INF>2.5 Network Costs
[Thousands of Actual Dollars]
----------------------------------------------------------------------------------------------------------------
Number of Number of Capital Sampling Filter Special Total
Year Sites Samplers Cost & QA Analysis Studies Cost
------------------------------------------------\1\--------------------------------\2\--------------------------
1997........................... 0 0 $4,500 ......... ........... ......... $4,500
1998........................... 724 861 $8,963 $10,216 $472 $1,426 $18,225
1999........................... 1,200 1,512 $14,877 $17,938 $2,325 $3,004 $38,143
2000........................... 1,500 1,887 $7,155 $26,697 $3,649 ......... $37,502
----------------------------------------------------------------------------------------------------------------
\1\ The PM<INF>2.5 network includes a mature network of 332 collocated samplers for QA purposes.
\2\ Three different types of filter analyses are anticipated (exceedance analyses, screening analyses, and
detailed analyses).

Table 3.--Cost for PM<INF>2.5 Filter Analyses
------------------------------------------------------------------------
Type of Filter Analysis Estimated Cost per Sample
------------------------------------------------------------------------
Exceedance Analysis $200
High PM<INF>2.5 concentration events are
analyzed for particle size and
composition utilizing optical or
electron microscopy.................. ............................
Screening Analysis $150
Multi-filter analyses including (1) x-
ray fluorescence (XRF) for elemental
composition (crustal material,
sulfur, and heavy metals); (2) ion
chromatography for ions such as
sulfate, nitrate, and chloride; (3)
thermal-optical analysis for
elemental/organic/total carbon....... ............................
Detailed Analysis $400
Analysis for speciated organic
composition.......................... ............................
------------------------------------------------------------------------

[[Page 38782]]

Table 4.--PM<INF>10 Network Costs
[Thousands of Actual Dollars]
----------------------------------------------------------------------------------------------------------------
Capital Cost Operation &
Year Number of Number of to Remove Maintenance Total Cost
Sites Samplers\1\ Sites Cost
----------------------------------------------------------------------------------------------------------------
1997............................ 1,650 1,810 .............. $15,861 $15,861
1998............................ 1,450 1,610 $137 $13,358 $13,495
1999............................ 1,250 1,410 $89 $11,946 $12,035
2000............................ 900 1,060 $159 $9,134 $9,293
----------------------------------------------------------------------------------------------------------------
\1\ The PM<INF>10 network includes 160 collocated samplers for QA purposes.

Table 5.--Costs for Particulate Monitoring
[In 1997 Dollars]
----------------------------------------------------------------------------------------------------------------
Annual Operation & Maintenance
PM Monitor and Sampling Frequency One-Time Capital Cost Cost
----------------------------------------------------------------------------------------------------------------
PM<INF>10 1-in-6 day sampling schedule....... $7,700 to $14,800................. $8,000 to $8,900
PM<INF>10 1-in-3 day sampling schedule....... $7,700 to $19,400................. $12,400
PM<INF>2.5 1-in-6 day sampling schedule...... $9,300 to $20,700................. $11,300 to $12,500
PM<INF>2.5 1-in-3 day sampling schedule...... $12,800 to $20,700................ $17,000 to $18,600
PM<INF>2.5 every day sampling................ $12,900 to $20,700................ $20,700 to $22,200
Nephelometer (continuous)............... $21,000........................... $19,700
----------------------------------------------------------------------------------------------------------------

V. References

(1) Information Collection Request, 40 CFR Part 58, Ambient Air
Quality Surveillance, OMB #2060-0084, EPA ICR No. 0940.14, U.S.
Environmental Protection Agency, Office of Air Quality Planning and
Standards, Research Triangle Park, NC 27711.

VI. Regulatory Assessment 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 Recordkeeping Requirements.

B. Paperwork Reduction Act

The information collection requirements contained in this 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 EPA (ICR No. 0940.14) and a copy may be obtained from
Sandy Farmer, Information Policy Branch, EPA, 401 M St., SW., Mail Code
2137, Washington, DC 20460; or by calling (202) 260-2740.
1. Need and use of the collection. The main use for the collection
of the data is to implement the air quality standards. 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 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, that requires ambient air quality
monitoring for purposes of the SIP and reporting of the data to EPA,
and section 319, that 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.
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 SIPs; providing
dispersion modeling support; developing responsible, cost-effective
control strategies; reconciling emission inventories; and developing
air quality trends. The collection of PM_2.5 data is
necessary to support the PM_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
regulations will submit these data electronically to the U.S. EPA's
Aerometric Information Retrieval System, Air Quality Subsystem (AIRS-
AQS). Quality assurance/quality control records and monitoring network
documentation are also maintained by each State/local agency, in AIRS-
AQS electronic format where possible.
2. Reporting and recordkeeping burden. The total annual collection
and reporting burden associated with this rule is estimated to be
785,430 hours. Of

[[Page 38783]]

this total, 778,826 hours are estimated to be for data reporting, or an
average of 5,991 hours for the estimated 130 respondents. The remainder
of 6,604 hours for recordkeeping burden averages 51 hours for the
estimated 130 respondents. The capital operation/maintenance costs
associated with this rule are estimated to be $32,463,626. 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
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 part 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.

C. Impact on Small Entities

Pursuant to section 605(b) of the Regulatory Flexibility Act, 5
U.S.C. 605(b), the EPA 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 signed into law on March 22, 1995, 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.
EPA has determined that this rule does not contain a Federal
mandate that may result in an administrative burden of $100 million or
more for State and local governments, in the aggregate, or the private
sector in any one year. The Agency's economic analysis indicates that
the total incremental administrative cost will be approximately
$56,611,000 in 1997 dollars for the 3 years to phase in the network, or
an average of $18,820,000 per year for the 3-year implementation
period. Table 6 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_2.5 monitoring
include the initial capital costs anticipated in 1997. In addition,
this rule imposes no enforceable duties on small businesses.

Table 6.--Cost Elements for PM Monitoring
--------------------------------------------------------------------------------------------------------------------------------------------------------
Administrative Cost Based on 3-year Average (thousands of constant 1997 dollars)*
---------------------------------------------------------------------------------------------------------------------------------------------------------
Current Revised
Cost/Element ---------------------------------------------------------------------------------------------- Net Change
PM<INF>10 PM<INF>10 PM<INF>2.5 Totals
--------------------------------------------------------------------------------------------------------------------------------------------------------
Network design $0 $1,174 $1,174 $1,174
Site installation $0 $1,532 $1,532 $1,532
Sampling & analysis $3,518 $2,528 $7,915 $10,443 $6,926
Maintenance $1,658 $1,192 $2,285 $3,477 $1,818
Data management $2,098 $1,508 $3,370 $4,878 $2,780
Quality assurance $2,940 $2,113 $3,342 $5,455 $2,515
Supervision $3,350 $2,408 $3,068 $5,476 $2,125
Summary $13,564 $9,749 $22,684 $32,433 $18,820
*Totals are rounded
--------------------------------------------------------------------------------------------------------------------------------------------------------

[[Page 38784]]

List of Subjects in 40 CFR Parts 53 and 58

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

Dated: July 16, 1997.

Carol M. Browner,
Administrator.
For the reasons set forth in the preamble, title 40, chapter I,
parts 53 and 58 of the Code of Federal Regulations are amended as follows:

PART 53--[AMENDED]

1. In part 53:
a. 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.

b. 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.

Terms used but not defined in this part shall have the meaning
given them by the Act.
Act means the Clean Air Act (42 U.S.C. 1857-1857l), as amended.
Administrator means the Administrator of the Environmental
Protection Agency or the Administrator's authorized representative.
Agency means the Environmental Protection Agency.
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, distributor,
supplier, or vendor.
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.
Candidate method means a method for measuring the concentration of
an air pollutant in the ambient air 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.
Class I equivalent method means an equivalent method for
PM_2.5 which is based on a sampler that is very similar to
the sampler specified for reference methods in Appendix L of this part,
with only minor deviations or modifications, as determined by EPA.
Class II equivalent method means an equivalent method for
PM_2.5 that utilizes a PM_2.5 sampler in which an
integrated PM_2.5 sample is obtained from the atmosphere by
filtration and is subjected to a subsequent filter conditioning 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 EPA.
Class III equivalent method means an equivalent method for
PM_2.5 that has been determined by EPA not to be a Class I or
Class II equivalent method. This fourth type of PM_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 are likely to use components and
methods other than those specified for reference method samplers.
Collocated describes two or more air samplers, analyzers, or other
instruments which sampler the ambient air that are operated
silmultaneously 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.
Equivalent method means a method for measuring the concentration of
an air pollutant in the ambient air 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.
ISO 9001-registered facility means a manufacturing facility that is
either:
(1) An International Organization for Standardization (ISO) 9001-
registered manufacturing facility, registered to the ISO 9001 standard
(by the Registrar Accreditation Board (RAB) of the American Society for
Quality Control (ASQC) in the United States), with registration
maintained continuously.
(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 an ISO 9001-
registered facility for the design and manufacture of designated
reference and equivalent method samplers and monitors.
ISO-certified auditor means an auditor who is either certified by
the Registrar Accreditation Board (in the United States) as being
qualified to audit quality systems using the requirements of recognized
standards such as ISO 9001, or who, based on information submitted to
the EPA, meets the same general requirements as provided for ISO-
certified auditors.
Manual method means a method for measuring concentrations of an
ambient air pollutant in which sample collection, analysis, or
measurement, or some combination therof, is performed manually. A
method for PM₁₀ or PM_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

[[Page 38785]]

automatically collecting a series of sequential samples.
PM_2.5 sampler means a device, associated with a manual
method for measuring PM_2.5, designed to collect
PM_2.5 from an ambient air sample, but lacking the ability to
automatically analyze or measure the collected sample to determine the
mass concentrations of PM_2.5 in the sampled air.
PM₁₀ sampler means a device, associated with a manual
method for measuring PM₁₀, designed to collect
PM₁₀ from an ambient air sample, but lacking the ability to
automatically analyze or measure the collected sample to determine the
mass concentrations of PM₁₀ in the sampled air.
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.
Sequential samples for PM samplers means two or more PM samples for
sequential (but not necessarily contiguous) time periods that are
collected automatically by the same sampler without the need for
intervening operator service.
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. Test sampler means a PM₁₀ sampler or a
PM_2.5 sampler subjected to testing as part of a candidate
method in accordance with subparts C, D, E, or F of this part.
Ultimate purchaser means the first person or entity who purchases a
reference method or an equivalent method for purposes other than resale.

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 sulfur dioxide
(SO<INF>2</INF>) 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</INF> and lead will not be considered for reference method
determinations under this part.
(2) A reference method for measuring PM₁₀ must be a
manual method that meets all requirements specified in Appendix J of
part 50 of this chapter and must include a PM₁₀ sampler that
has been shown in accordance with this part to meet all requirements
specified in subparts A and D of this part.
(3) A reference method for measuring PM_2.5 must be a
manual method that meets all requirements specified in Appendix L of
part 50 of this chapter and must include a PM_2.5 sampler
that has been shown in accordance with this part to meet the applicable
requirements specified in subparts A and E of this part. Further,
reference method samplers must be manufactured in an ISO 9001-
registered facility, as defined in Sec. 53.1 and as set forth in
Sec. 53.51, and the Product Manufacturing Checklist set forth in
subpart E of this part must be completed by an ISO-certified auditor,
as defined in Sec. 53.1, and submitted to EPA annually to retain a
PM_2.5 reference method designation.
(b) Automated methods. An automated reference method for measuring
carbon monoxide (CO), ozone (O<INF>3</INF>), and nitrogen dioxide
(NO<INF>2</INF>) 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, PM₁₀ or
PM_2.5 samplers associated with manual equivalent methods for
PM₁₀ or PM_2.5 must have been shown in accordance
with this part to satisfy the following additional requirements:
(1) A PM₁₀ sampler associated with a manual method for
PM₁₀ must satisfy the requirements of subpart D of this
part.
(2) A PM_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_2.5 Class II equivalent method sampler must
satisfy the applicable requirements of subparts C, E, and F of this part.
(4) Requirements for PM_2.5 Class III equivalent method
samplers 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 and may include selected requirements from subparts
C, E, or F of this part or other requirements not contained in this part.
(5) All designated equivalent methods for PM_2.5 must be
manufactured in an ISO 9001-registered facility, as defined in
Sec. 53.1 and as set forth in Sec. 53.51, and the Product Manufacturing
Checklist set forth in subpart E of this part must be completed by an
ISO-certified auditor, as defined in Sec. 53.1, and submitted to EPA
annually to retain a PM_2.5 equivalent method designation.
(b) Automated methods. (1) Automated equivalent methods for
pollutants other than PM_2.5 or PM₁₀ 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 PM₁₀ 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_2.5 Class III automated
equivalent methods for PM_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 and may include
selected requirements from subparts C, E, or F of this part or other
requirements not contained in this part.
(4) All designated equivalent methods for PM_2.5 must be
manufactured in an ISO 9001-registered facility, as set forth in
subpart E of this part, and the Product Manufacturing Checklist set
forth in subpart E of this part must be completed by an ISO-certified
auditor and submitted to EPA annually to retain a PM_2.5
equivalent method designation.
(5) All designated equivalent methods for PM_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.

[[Page 38786]]

(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 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_2.5 must meet all applicable requirements in Reference
1 of Appendix A of this subpart, using appropriate graphical,
nomenclature, and mathematical conventions such as those specified in
References 3 and 4 of Appendix A of this subpart.
(3) A copy of a comprehensive operation or instruction manual
providing a complete and detailed description of the operational,
maintenance, and calibration procedures prescribed for field use of the
candidate method and all instruments utilized as part of that method
(under Sec. 53.9(a)).
(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.
(K) Appropriate references to Appendix L of part 50 of this
chapter; Reference 6 of Appendix A of this subpart; 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 EPA. For samplers and automated methods, the manual shall include a
clear description of all procedures pertaining to installation,
operation, preventive maintenance, and troubleshooting and shall also
include parts identification diagrams. The manual may be used to
satisfy the requirements of paragraphs (b)(1) and (b)(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) Descriptions of test facilities and test configurations, 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 of Appendix A of this subpart,
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
National Institute of Standards and Technology (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 PM₁₀ and PM_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_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 of
Appendix A of this subpart: 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).
(2) A description of the durability characteristics of such
analyzers or samplers (see Sec. 53.9(c)). For methods for
PM_2.5, the warranty program must

[[Page 38787]]

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
for 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.
(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 in Appendix A of
this subpart 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_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 27711, 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 EPA determines to be necessary or appropriate under
Sec. 53.5(f), and such tests may include special tests not 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 EPA. Upon completion of EPA testing, the analyzer
or sampler submitted under this paragraph shall be repacked by EPA for
return shipment to the applicant, using the same packing materials used
for shipping the instrument to EPA unless alternative packing is
provided by the applicant. Arrangements for, and the cost of, return
shipment shall be the responsibility of the applicant. 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 the tests 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.
(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 1 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

[[Page 38788]]

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 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 to 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, PM₁₀ sampler, or PM_2.5
sampler offered for sale as part of a reference or equivalent method
shall function within the limits of the performance specifications
referred to in Sec. 53.20(a), Sec. 53.30(a), Sec. 53.50, or Sec. 53.60,
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, PM₁₀ sampler, or PM_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 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, PM₁₀ samplers, or
PM_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_2.5 or PM₁₀ 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, PM₁₀ sampler,
or PM_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, PM₁₀ sampler, or
PM_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_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 9001-registered
facility, as set forth in subpart E of this part. In the event that the
ISO 9001 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
9001-registered facility, the applicant shall notify EPA within 30 days
of the date the facility becomes other than an ISO 9001-registered
facility, and upon such notification, EPA shall issue a preliminary
finding and notification of possible cancellation of the reference or
equivalent method designation under Sec. 53.11.
(i) An applicant who has offered PM_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 EPA
within 12 months of the date of the last such submitted Checklist or
Checklist update, 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 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

[[Page 38789]]

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.
(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 EPA, 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 EPA in any hearing under this section.
(5) Each party other than EPA 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 EPA.
(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/her 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
therefore 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
Administrator will include written findings and conclusions and the
reasons or basis therefore 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 EPA Administrator prior to
implementation any intended modification of the

[[Page 38790]]

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.
(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).
(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 1 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 part
50 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.
(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 the test shall
be interpreted (in such cases, the 120-day period shall commence upon
receipt of the additional test data).
(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 commence 1 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 of proposed rulemaking
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.

[[Page 38791]]

(C) To cancel equivalent method designations based on the existing
reference method(s).
(ii) The notice of proposed rulemaking 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)(i) 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:
(A) Promulgate the proposed revision, with such modifications as
may be appropriate in view of comments received.
(B) Where the appendix to part 50 (prior to revision) specifies a
measurement principle and calibration procedure, cancel reference
method designations based on the appendix.
(C) Cancel equivalent method designations based on the existing
reference method(s).
(D) 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.
(3) 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.
(4) 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.
(5) 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.

Tables to Subpart A of Part 53

Table A-1.--Summary of Applicable Requirements for Reference and Equivalent Methods for Air Monitoring of Criteria Pollutants
--------------------------------------------------------------------------------------------------------------------------------------------------------
Applicable Subparts of part 53
Pollutant Ref. or Equivalent Manual or Automated Applicable part 50 -----------------------------------------------
Appendix A B C D E F
--------------------------------------------------------------------------------------------------------------------------------------------------------
SO<INF>2................................. Reference............. Manual................ A ...... ...... ...... ...... ...... ......
Manual................ .................. <check ...... <check ...... ...... ......
> >
Equivalent............ Automated............. .................. <check <check <check ...... ...... ......
> > >
CO.................................. Reference............. Automated............. C <check <check ...... ...... ...... ......
> >
Manual................ .................. <check ...... <check ...... ...... ......
> >
Equivalent............ Automated............. .................. <check <check <check ...... ...... ......
> > >
O<INF>3.................................. Reference............. Automated............. D <check <check ...... ...... ...... ......
> >
Manual................ .................. <check ...... <check ...... ...... ......
> >
Equivalent............ Automated............. .................. <check <check <check ...... ...... ......
> > >
NO<INF>2................................. Reference............. Automated............. F <check <check ...... ...... ...... ......
> >
Manual................ .................. <check ...... <check ...... ...... ......
> >
Equivalent............ Automated............. .................. <check <check <check ...... ...... ......
> > >
Pb.................................. Reference............. Manual................ G ...... ...... ...... ...... ...... ......
Equivalent............ Manual................ .................. <check ...... <check ...... ...... ......
> >
PM<INF>10................................ Reference............. Manual................ J <check ...... ...... <check ...... ......
> >
Manual................ .................. <check ...... <check <check ...... ......
> > >
Equivalent............ Automated............. .................. <check ...... <check <check ...... ......
> > >
PM<INF>2.5............................... Reference............. Manual................ L <check ...... ...... ...... <check ......
> >
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\ Note: 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.

Appendix A to Subpart A of Part 53--References
(1) 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.
(2) American National Standard--Specifications and Guidelines
for Quality Systems for Environmental Data Collection and
Environmental Technology Programs, ANSI/ASQC E41994. Available from
American Society for Quality Control, 611 East Wisconsin Avenue,
Milwaukee, WI 53202.
(3) Dimensioning and Tolerancing, ASME Y14.5M-1994. Available
from the American Society of Mechanical Engineers, 345 East 47th
Street, New York, NY 10017.
(4) 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.
(5) 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.
(6) Copies of section 2.12 of the Quality Assurance Handbook for
Air Pollution

[[Page 38792]]

Measurement Systems, Volume II, Ambient Air Specific Methods, EPA/
600/R-94/038b, are available from Department E (MD-77B), U.S. EPA,
Research Triangle Park, NC 27711.
c. 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</INF>, CO,
O<INF>3</INF>, and NO<INF>2</INF>.
53.33 Test procedure for methods for lead.
53.34 Test procedure for methods for PM₁₀ and
PM_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.--Test Specifications for PM₁₀ and
PM_2.5 Methods
Figures to Subpart C of Part 53
Figure C-1.--Suggested Format for Reporting Test Results
Appendix A to Subpart C of 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</INF>, CO, O<INF>3</INF>,
and NO<INF>2</INF> methods when the differences between:
(i) Measurements made by a candidate manual method or by a test
analyzer representative of a candidate automated method.
(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.
(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 PM₁₀ and PM_2.5
methods when the relationship between:
(i) Measurements made by a candidate method.
(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</INF>, CO, O<INF>3</INF>, and
NO<INF>2</INF>. 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 described under
paragraph (d)(2) of this section.
(3) Methods for Pb. 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 PM₁₀. 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 PM₁₀ concentrations in the specified
ranges.
(5) Methods for PM_2.5. Augmentation of pollutant
concentrations is not permitted, hence appropriate test sites must be
selected to provide PM_2.5 concentrations and
PM_2.5/PM₁₀ 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_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 must be selected such that all acceptable test sample sets, as
defined in Sec. 53.34(c)(3), have a PM_2.5/PM₁₀
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_2.5/PM₁₀ ratio of less than 0.40. At least two
reference method PM₁₀ samplers shall be collocated with the
candidate and reference method PM_2.5 samplers and operated
simultaneously with the other samplers at each test site to measure
concurrent ambient concentrations of PM₁₀ to determine the
PM_2.5/PM₁₀ ratio for each sample set. The
PM_2.5/PM₁₀ ratio for each sample set shall be the
average of the PM_2.5 concentration, as determined in
Sec. 53.34(c)(1), divided by the average PM₁₀ concentration,
as measured by the PM₁₀ samplers. The tests at the two sites
may be conducted in different calendar seasons, if appropriate, to
provide PM_2.5 concentrations and PM_2.5/
PM₁₀ 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 Tables 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</INF>, CO, O<INF>3</INF>, and
NO<INF>2</INF>. 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 ensure that identical samples reach the two methods. If
necessary, the concentration of pollutant in the sampled ambient air
may be augmented

[[Page 38793]]

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 Pb, PM₁₀ and PM_2.5. The
ambient air intake points of all the candidate and reference method
collocated samplers for lead, PM₁₀ or PM_2.5 shall
be positioned at the same height above the ground level, and between 2
and 4 meters apart. The samplers shall be oriented in a manner that
will minimize spatial and wind directional effects on sample collection.
(4) PM₁₀ methods employing the same sampling procedure
as the reference method but a different analytical method. Candidate
methods for PM₁₀ 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_2.5, all submitted information must meet the requirements
of the ANSI/ASQC E4 Standard, 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.C 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. (1) 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).
(2) For a candidate method having more than one selectable range,
one range must be that specified in Table B-1 of subpart B of this part
and a test analyzer representative of the method must pass the tests
required by this subpart while operated on that range. The tests may be
repeated for a broader range (i.e., one extending to higher
concentrations) than the one specified in Table B-1 of subpart B of
this part, provided that the range does not extend to concentrations
more than two times the upper range limit specified in Table B-1 of
subpart B of this part and that the test analyzer has passed the tests
required by subpart B of this part (if applicable) for the broader
range. If the tests required by this subpart are conducted or passed
only for the range specified in Table B-1 of subpart B of this part,
any equivalent method determination with respect to the method will be
limited to that range. If the tests are passed for both the specified
range and a broader range (or ranges), any such determination will
include the broader range(s) as well as the specified range.
Appropriate test data shall be submitted for each range sought to be
included in such a determination.
(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 as specified in the manual referred to in
Sec. 53.4(b)(3) is permitted only every 3 days. Automatic adjustments
which the test analyzer performs by itself are permitted at any time.
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</INF>, CO,
O<INF>3</INF>, and NO<INF>2</INF>.

(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 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</INF>
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. Figure C-
1 of this subpart contains a suggested format for reporting the test
results.
(c) The results of the first set of measurements shall be
interpreted as follows:

[[Page 38794]]

(1) Zero failures. The candidate method passes the test for
comparability.
(2) Three or more failures. The candidate method fails the test for
comparability.
(3) One or two 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 or two failures. The candidate method passes the test for
comparability.
(ii) Three or more failures. The candidate method fails the test
for comparability.
(4) For SO<INF>2</INF>, 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 24 sequential 1-hour measurements.
(f) For ozone and carbon monoxide, no more than six 1-hour
measurements shall be made per day. For sulfur dioxide, no more than
four 1-hour measurements or one 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
address given in Sec. 53.4(a). 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 samples and
the audit samples, analyze each filter extract three 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</INF>, R<INF>1B</INF>, R<INF>1C</INF>, R<INF>2A</INF>,
R<INF>2B</INF>, ..., Q<INF>1A</INF>, Q<INF>1B</INF>, Q<INF>1C</INF>,
..., where R denotes results from the reference method samples; Q
denotes results from the audit samples; 1, 2, 3 indicate the filter
number, and A, B, C indicate 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 concentrates in <greek-m>g/m3
for each analysis of each filter. Label these test results as
C<INF>1A</INF>, C<INF>1B</INF>, C<INF>2C</INF>, ..., where C denotes
results from the candidate method. For candidate methods which provide
a direct measurement of lead concentrations without a separable
procedure, C<INF>1A</INF>=C<INF>1B</INF>=C<INF>1C</INF>,
C<INF>2A</INF>=C<INF>2B</INF>=C<INF>2C</INF>, etc.
(d) Average lead concentration. For the reference method, calculate
the average lead concentration for each filter by averaging the
concentrations calculated from the three analyses:

Equation 1
[GRAPHIC] [TIFF OMITTED] TR18JY97.052

where:
i is the filter number.

(e) Acceptable filter pairs. 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:

Equation 2
[GRAPHIC] [TIFF OMITTED] TR18JY97.053

Equation 3
[GRAPHIC] [TIFF OMITTED] TR18JY97.054

where:
i indicates the filter number.
(2) If any reference method precision value (P<INF>Ri</INF>)
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 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</INF>)
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</INF>'s and all P<INF>Ci</INF>'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:

Equation 4
[GRAPHIC] [TIFF OMITTED] TR18JY97.055

where:
i is audit sample number.

[[Page 38795]]

(ii) Calculate the percent difference (D<INF>q</INF>) between the
indicated lead concentration for each audit sample and the true lead
concentration (T<INF>q</INF>) as follows:

Equation 5
[GRAPHIC] [TIFF OMITTED] TR18JY97.056

(2) If any difference value (D<INF>qi</INF>) 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:

Equation 6
[GRAPHIC] [TIFF OMITTED] TR18JY97.057

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) exceeds <plus-minus> 20
percent, the candidate method passes the test for comparability.
(3) If one or more of the percent differences (D) exceeds
<plus-minus> 20 percent, the candidate method fails the test for
comparability.
(i) The candidate method must pass both the precision test
(paragraph (f) of this section) and the comparability test (paragraph
(h) of this section) to qualify for designation as an equivalent method.

Sec. 53.34 Test procedure for methods for PM₁₀ and
PM_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 PM₁₀ or
PM_2.5 measurements as necessary (see paragraph (c)(3) of
this section), each set consisting of three reference method and three
candidate method measurements, all obtained simultaneously. For
PM_2.5 candidate Class II equivalent methods, at least two
collocated PM₁₀ reference method samplers are also required
to obtain PM_2.5/PM₁₀ ratios for each sample set.
Candidate PM₁₀ method measurements shall be 24-hour
integrated measurements; PM_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 PM₁₀ or
PM_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_2.5 methods is found in section 2.12 of the
Quality Assurance Handbook (Reference 6 of Appendix A to subpart A of
this part).
(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.
(c) Test for comparability and precision. (1) For each of the
measurement sets, calculate the average PM₁₀ or
PM_2.5 concentration obtained with the reference method
samplers:

Equation 7
[GRAPHIC] [TIFF OMITTED] TR18JY97.058

where:
R denotes results from the reference method;
i is the sampler number; and
j is the set.
(2)(i)(A) For each of the measurement sets, calculate the precision
of the reference method PM₁₀ or PM_2.5
measurements as:

Equation 8
[GRAPHIC] [TIFF OMITTED] TR18JY97.059

(B) If the corresponding j is below:
80 <greek-m>g/m3 for PM₁₀ methods.
40 <greek-m>g/m3 for 24-hour PM_2.5 at
single test sites for Class I candidate methods.
40 <greek-m>g/m3 for 24-hour PM_2.5 at
sites having PM_2.5/PM₁₀ ratios >0.75.
30 <greek-m>g/m3 for 48-hour PM_2.5 at
single test sites for Class I candidate methods.
30 <greek-m>g/m3 for 48-hour PM_2.5 at
sites having PM_2.5/PM₁₀ ratios >0.75.
30 <greek-m>g/m3 for 24-hour PM_2.5 at
sites having PM_2.5/PM₁₀ ratios <0.40.
20 <greek-m>g/m3 for 48-hour PM_2.5 at
sites having PM_2.5/PM₁₀ ratios >0.75.

(ii) Otherwise, calculate the precision of the reference method
PM₁₀ or PM_2.5 measurements as:

Equation 9
[GRAPHIC] [TIFF OMITTED] TR18JY97.060

(3) If j falls outside the acceptable concentration range specified
in Table C-4 of this subpart for any set, or if Pj or RPj, 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_2.5/PM₁₀ 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 PM₁₀ or PM_2.5 concentration obtained with
the candidate method samplers:

Equation 10
[GRAPHIC] [TIFF OMITTED] TR18JY97.061

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 PM₁₀ or
PM_2.5 measurements obtained with the candidate method
(C<INF>j</INF>) against the corresponding average PM₁₀ or
PM_2.5 measurements obtained with the reference method
(R<INF>j</INF>). For each site, calculate and record the linear
regression slope and intercept, and the correlation coefficient.
(6) If the linear regression parameters calculated under paragraph
(c)(5) of this section meet the values specified in Table C-4 of this
subpart for all test sites, the candidate method passes the test for
comparability.

[[Page 38796]]

Tables to Subpart C of Part 53

Table C-1.--Test Concentration Ranges, Number of Measurements Required, and Maximum Discrepancy Specification
--------------------------------------------------------------------------------------------------------------------------------------------------------
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
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ozone................................. Low 0.06 to 0.10.......................... 5 6 ........... ........... 0.02
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
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
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
Med 0.10 to 0.20.......................... ........... ........... 2 3 .03
High 0.25 to 0.35......................... ........... ........... 2 2 .03
---------------------------------------------------------------------
Total.................................. ........... ........... 7 8 ................
--------------------------------------------------------------------------------------------------------------------------------------------------------

Table C-2.--Sequence of Test Measurements
------------------------------------------------------------------------
Concentration Range
Measurement ----------------------------------------
First Set Second Set
------------------------------------------------------------------------
1.............................. Low Medium
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
------------------------------------------------------------------------

------------------------------------------------------------------------
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
n5
Maximum difference, percent of reference method............... <plus-mi
n20
------------------------------------------------------------------------

Table C-4.--Test Specifications for PM<INF>10 and PM<INF>2.5 Methods
----------------------------------------------------------------------------------------------------------------
PM<INF>2.5
Specification PM<INF>10 -----------------------------------------------------
Class I Class II
----------------------------------------------------------------------------------------------------------------
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....................... ......................... .........................
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 ....................... 3........................ .........................
for 24-hr or R<INF>j < 30
<greek-m>g/m3 for 48-
hr samples.
R<INF>j > 40 <greek-m>g/m3 ....................... 3........................ .........................
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 ....................... ......................... 3
for 24-hr or R<INF>j < 30
<greek-m>g/m3 for 48-
hr samples.
R<INF>j > 40 <greek-m>g/m3 ....................... ......................... 3
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 ....................... ......................... 3
for 24-hr or R<INF>j < 20
<greek-m>g/m3 for 48-
hr samples.

[[Page 38797]]

R<INF>j > 30 <greek-m>g/m3 ....................... ......................... 3
for 24-hr or R<INF>j > 20
<greek-m>g/m3 for 48-
hr samples.
Total, each site............... ....................... 10....................... 10
Precision of replicate 5 <greek-m>g/m3 or 7%.... 2 <greek-m>g/m3 or 5%.... 2 <greek-m>g/m3 or 5%
reference method measurements,
P<INF>j or RP<INF>j respectively,
maximum.
Slope of regression 1<plus-minus>0.1......... 1<plus-minus>0.05........ 1<plus-minus>0.05
relationship.
Intercept of regression 0<plus-minus>5........... 0<plus-minus>1........... 0<plus-minus>1
relationship, <greek-m>g/m3.
Correlation of reference method <gr-thn-eq>0.97.......... <gr-thn-eq>0.97.......... <gr-thn-eq>0.97
and candidate method
measurements.
----------------------------------------------------------------------------------------------------------------

[[Page 38798]]

Figures to Subpart C of Part 53

Figure C-1.--Suggested Format for Reporting Test Results
Candidate Method------------------------------------------------------------
Reference Method------------------------------------------------------------
Applicant----------------------------------------------------------------------
First Set Second Set Type 1 Hour 24 Hour
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Concentration, ppm
Concentration Range Date Time ---------------------------------------- Difference Table C-1 Spec. Pass or Fail
Candidate Reference
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Low 1
---------- ppm
to -------- ppm
---------------------------------------------------------------------------------------------------------------------------------------------------------------
2
---------------------------------------------------------------------------------------------------------------------------------------------------------------
3
---------------------------------------------------------------------------------------------------------------------------------------------------------------
4
---------------------------------------------------------------------------------------------------------------------------------------------------------------
5
---------------------------------------------------------------------------------------------------------------------------------------------------------------
6
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Medium 1
---------- ppm
to -------- ppm
---------------------------------------------------------------------------------------------------------------------------------------------------------------
2
---------------------------------------------------------------------------------------------------------------------------------------------------------------
3
---------------------------------------------------------------------------------------------------------------------------------------------------------------
4
---------------------------------------------------------------------------------------------------------------------------------------------------------------
5
---------------------------------------------------------------------------------------------------------------------------------------------------------------
6
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
High 1
---------- ppm
to -------- ppm
---------------------------------------------------------------------------------------------------------------------------------------------------------------
2
---------------------------------------------------------------------------------------------------------------------------------------------------------------
3
---------------------------------------------------------------------------------------------------------------------------------------------------------------
4
---------------------------------------------------------------------------------------------------------------------------------------------------------------
5
---------------------------------------------------------------------------------------------------------------------------------------------------------------
6
---------------------------------------------------------------------------------------------------------------------------------------------------------------
7
---------------------------------------------------------------------------------------------------------------------------------------------------------------
8
---------------------------------------------------------------------------------------------------------------------------------------------------------------
Total
Failures:
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

[[Page 38799]]

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.
d. 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_2.5
Sec.
53.50 General provisions.
53.51 Demonstration of compliance with design specifications and
manufacturing and test requirements.
53.52 Leak check test.
53.53 Test for flow rate accuracy, regulation, measurement
accuracy, and cut-off.
53.54 Test for proper sampler operation following power
interruptions.
53.55 Test for effect of variations in power line voltage and
ambient temperature.
53.56 Test for effect of variations in ambient pressure.
53.57 Test for filter temperature control during sampling and
post-sampling periods.
53.58 Operational field precision and blank test.
53.59 Aerosol transport test for Class I equivalent method samplers.
Tables to Subpart E of Part 53
Table E-1.--Summary of Test Requirements for Reference and Class I
Equivalent Methods for PM_2.5.
Table E-2.--Spectral Energy Distribution and Permitted Tolerance for
Conducting Radiative Tests.
Figures to Subpart E of Part 53
Figure E-1--Designation Testing Checklist
Figure E-2--Product Manufacturing Checklist
Appendix A 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_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_2.5
sampler associated with a candidate reference method or Class I
equivalent method meets all design and performance specifications set
forth in 40 CFR part 50, Appendix L, as well as additional requirements
specified in this subpart E. Some of these tests may also be applicable
to portions of a candidate Class II equivalent method sampler, as
determined under subpart F of this part. Some or all of these tests may
also be applicable to a candidate Class III equivalent method sampler,
as may be determined under Sec. 53.3(a)(4) or Sec. 53.3(b)(3).
(b) Samplers associated with candidate reference methods for
PM_2.5 shall be subject to the provisions, specifications,
and test procedures prescribed in Secs. 53.51 through 53.58. Samplers
associated with candidate Class I equivalent methods for
PM_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 equivalent methods for
PM_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) The provisions of Sec. 53.51 pertain to test results and
documentation required to demonstrate compliance of a candidate method
sampler with the design specifications set forth in 40 CFR part 50,
Appendix L. The test procedures prescribed in Secs. 53.52 through 53.59
pertain to performance tests required to demonstrate compliance of a
candidate method sampler with the performance specifications set forth
in 40 CFR part 50, Appendix L, 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.
(d) Test procedures prescribed in Sec. 53.59 do not apply to
candidate reference method samplers. These procedures apply primarily
to candidate Class I equivalent method samplers for PM_2.5
which have a sample air flow path configuration upstream of the sample
filter that is modified with respect to that specified for the
reference method sampler, as set forth in 40 CFR part 50, Appendix L,
Figures L-1 to L-29, such as might be necessary 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 sample filter. In addition to the other test procedures in this
subpart, these test procedures shall be used to further test the
performance of such an equivalent method sampler against the
performance specifications given in the procedure and summarized in
Table E-1 of this subpart.
(e) A 10-day operational field test of measurement precision is
required under Sec. 53.58 for both candidate reference and equivalent
method samplers. This test requires collocated operation of three
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.
(f) All tests and collection of test data shall be performed 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 Demonstration of compliance with design specifications and
manufacturing and test requirements.

(a) Overview. (1) The subsequent paragraphs of this section specify
certain documentation that must be submitted and tests that are
required to demonstrate that samplers associated with a designated
reference or equivalent method for PM_2.5 are properly
manufactured to meet all applicable design and performance
specifications and have been properly tested according to all
applicable test requirements for such designation. Documentation is
required to show that instruments and components of a PM_2.5
sampler are manufactured in an ISO 9001-registered facility under a
quality system that meets ISO-9001 requirements for manufacturing
quality control and testing.
(2) 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, based on a reasonable and appropriate sample
of the actual operations or their documented records. Following
designation of the method, another checklist is required, initially

[[Page 38800]]

and annually, to provide an ISO-certified auditor's certification that
the sampler manufacturing process is being implemented under an
adequate and appropriate quality system.
(3) For the purposes of this section, the definitions of ISO 9001-
registered facility and ISO-certified auditor are found in Sec. 53.1.
An exception to the reliance by EPA on ISO affiliate audits is the
requirement for the submission of the operation or instruction manual
associated with the candidate method to EPA as part of the application.
This manual is required under Sec. 53.4(b)(3). 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 performed by EPA.
(b) ISO registration of manufacturing facility. (1) The applicant
must submit documentation verifying that the samplers identified and
sold as part of a designated PM_2.5 reference or equivalent
method will be manufactured in an ISO 9001-registered facility 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 registration to ISO-9001. In this case, the applicant must
provide documentation in the application to demonstrate, by required
ISO-certified auditor's inspections, that a quality system is in place
which is adequate to document and monitor that the sampler system
components and final assembled samplers all conform to the design,
performance and other requirements specified in this part and in 40 CFR
part 50, Appendix L.
(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_2.5 that utilizes a sampler manufactured in a facility
that is not ISO 9001-registered or otherwise approved by 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 facility 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_2.5
samplers to be sold as part of a reference or equivalent method and
that are specified by design in 40 CFR part 50, Appendix L, are
fabricated or manufactured exactly as specified. If the manufacturer's
quality records show that its quality control (QC) and quality
assurance (QA) system of standard process control inspections (of a set
number and frequency of testing that is less than 100 percent) complies
with the applicable QA provisions of section 4 of Reference 4 in
Appendix A of this subpart and prevents nonconformances, 100 percent
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. Refer
also to 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_2.5 impactor jet diameter. The diameter of the jet of each
impactor manufactured for a PM_2.5 sampler under the impactor
design specifications set forth in 40 CFR part 50, Appendix L, shall be
verified against the tolerance specified on the drawing, using
standard, NIST-traceable ZZ go/no go 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. The manufacturer shall
submit evidence that this procedure is incorporated into the
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 Appendix
A of this subpart) 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 sensor, 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-certified auditor.
(f) Manufacturer's audit checklists. Manufacturers shall require an
ISO-certified auditor to sign and date a statement indicating that the
auditor is aware of the appropriate manufacturing specifications
contained in 40 CFR part 50, Appendix L, and the test or verification
requirements in this subpart. Manufacturers shall also require an ISO-
certified auditor 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 manufacture.
(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 an
ISO-certified auditor to complete a Product Manufacturing Checklist
(Figure E-2 of this subpart), 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
initial completed checklist shall be submitted with the application for
reference or equivalent method determination. Also, this checklist
(Figure E-2 of this subpart) must be completed and submitted annually to

[[Page 38801]]

retain a reference or equivalent method designation for a
PM_2.5 method.
(3) Phase-in period. If the conditions of paragraph (b)(2) of this
section apply, a candidate reference or equivalent method for
PM_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 (f)(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 Leak check test.

(a) Overview. In section 7.4.6 of 40 CFR part 50, Appendix L, the
sampler is required to include the 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 test 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. The test conditions and
performance specifications associated with this test are summarized in
Table E-1 of this subpart. The candidate test sampler must meet all
test parameters and test specifications to successfully pass this 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 mL/min to 130 mL/min, 2 percent certified accuracy, NIST-traceable.
(2) Flow rate measurement adaptor (40 CFR part 50, Appendix L,
Figure L-30) or equivalent adaptor to facilitate measurement of sampler
flow rate at the top of the downtube.
(3) Impermeable membrane or disk, 47 mm nominal diameter.
(4) Means, such as a micro-valve, of providing a simulated leak
flow rate through the sampler of approximately 80 mL/min under the
conditions specified for the leak check in the sampler's leak check
procedure.
(5) Teflon sample filter, as specified in section 6 of 40 CFR part
50, Appendix L.
(d) Calibration of test measurement instruments. Submit
documentation showing evidence of appropriately recent calibration,
certification of calibration accuracy, and NIST-traceability (if
required) of all measurement instruments used in the tests. The
accuracy of flow rate 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
use for this test.
(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_2.5 samples,
except that the sample air inlet shall be removed and the 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 80 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 80 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 the impermeable membrane in a filter
cassette and install the cassette into the sampler. Carry out the
internal leak check procedure as described in the sampler's operation/
instruction manual and verify that the leak check acceptance criterion
specified in Table E-1 of this subpart is met.
(2) Replace the impermeable membrane with a Teflon filter and
install the cassette in the sampler. Remove the inlet from the sampler
and install the flow measurement adaptor on the sampler's downtube.
Close the valve of the adaptor to seal the flow system. Conduct the
external leak check procedure as described in the sampler's operation/
instruction manual and verify that the leak check acceptance criteria
specified in Table E-1 of this subpart are met.
(3) Arrange the flow control device, flow rate measurement device,
and other apparatus as necessary to provide a simulated leak flow rate
of 80 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 80 mL/min.
(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 leak check procedure properly identifies the
occurrence of the simulated external leak of 80 mL/min.

Sec. 53.53 Test for flow rate accuracy, regulation, measurement
accuracy, and cut-off.

(a) Overview. This test procedure is designed to evaluate a
candidate sampler's flow rate accuracy with respect to the design flow
rate, flow rate regulation, flow rate measurement accuracy, coefficient
of variability measurement accuracy, and the flow rate cut-off
function. The tests for the first four parameters shall be conducted
over a 6-hour time period during which reference flow measurements are
made at intervals not to exceed 5 minutes. The flow rate cut-off test,
conducted separately, is intended to verify that the sampler carries
out the required automatic sample flow rate cut-off function properly
in the event of a low-flow condition. The test conditions and
performance specifications associated with this test are summarized in
Table E-1 of this subpart. The candidate test sampler must meet all
test parameters and test specifications to successfully pass this test.
(b) Technical definitions. (1) 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.
(2) 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 deviates by more than the variation
limits specified in Table E-1 of this subpart (<plus-minus>10 percent
from the nominal sample flow rate) for more than 60 seconds during a
sample collection period. The sampler is also required to properly
notify the operator with a flag warning indication of the out-of-
specification flow rate condition and if the flow rate cut-off results
in an elapsed sample collection time of less than 23 hours.
(c) Required test equipment. (1) Flow rate meter, suitable for
measuring and recording the actual volumetric sample flow rate at the
sampler downtube, with

[[Page 38802]]

a minimum range of 10 to 25 L/min, 2 percent certified, NIST-traceable
accuracy. Optional capability for continuous (analog) recording
capability or digital recording at intervals not to exceed 30 seconds
is recommended. While a flow meter which provides a direct indication
of volumetric flow rate is preferred for this test, an alternative
certified flow measurement device may be used as long as appropriate
volumetric flow rate corrections are made based on measurements of
actual ambient temperature and pressure conditions.
(2) Ambient air temperature sensor, with a resolution of 0.1 deg.C
and certified to be accurate to within 0.5 deg.C (if needed). If the
certified flow meter does not provide direct volumetric flow rate
readings, ambient air temperature measurements must be made using
continuous (analog) recording capability or digital recording at
intervals not to exceed 5 minutes.
(3) Barometer, range 600 mm Hg to 800 mm Hg, certified accurate to
2 mm Hg (if needed). If the certified flow meter does not provide
direct volumetric flow rate readings, ambient pressure measurements
must be made using continuous (analog) recording capability or digital
recording at intervals not to exceed 5 minutes.
(4) Flow measurement adaptor (40 CFR part 50, Appendix L, Figure L-
30) or equivalent adaptor to facilitate measurement of sample flow rate
at the sampler downtube.
(5) Valve or other means to restrict or reduce the sample flow rate
to a value at least 10 percent below the design flow rate (16.67 L/
min). If appropriate, the valve of the flow measurement adaptor may be
used for this purpose.
(6) 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.
(7) Teflon sample filter, as specified in section 6 of 40 CFR part
50, Appendix L (if required).
(d) Calibration of test measurement instruments. Submit
documentation showing evidence of appropriately recent calibration,
certification of calibration accuracy, and NIST-traceability (if
required) of all measurement instruments used in the tests. The
accuracy of flow-rate meters shall be verified at the highest and
lowest pressures and temperatures used in the tests and shall be
checked at zero and at least one flow rate within <plus-minus>3 percent
of 16.7 L/min within 7 days prior to use for this test. 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) Setup of the sampler shall be as required in
this paragraph (e) and otherwise 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_2.5 samples. A sample filter
and (or) the device for creating an additional 55 mm Hg pressure drop
shall be installed for the duration of these tests. The sampler's
ambient temperature, ambient pressure, and flow rate measurement
systems shall all be calibrated per the sampler's operation or
instruction manual within 7 days prior to this test.
(2) The inlet of the candidate sampler shall be removed and the
flow measurement adaptor installed on the sampler's downtube. A leak
check as described in the sampler's operation or instruction manual
shall be conducted and must be properly passed before other tests are
carried out.
(3) The inlet of the flow measurement adaptor shall be connected to
the outlet of the flow rate meter.
(4) For the flow rate cut-off test, the valve or means for reducing
sampler flow rate shall be installed between the flow measurement
adaptor and the downtube or in another location within the sampler such
that the sampler flow rate can be manually restricted during the test.
(f) Procedure. (1) Set up the sampler as specified in paragraph (e)
of this section and otherwise 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 6-hour
sample collection period at a convenient time.
(2) During the 6-hour operational flow rate portion of the test,
measure and record the sample flow rate with the flow rate meter at
intervals not to exceed 5 minutes. If ambient temperature and pressure
corrections are necessary to calculate volumetric flow rate, ambient
temperature and pressure shall be measured at the same frequency as
that of the certified flow rate measurements. Note and record the
actual start and stop times for the 6-hour flow rate test period.
(3) Following completion of the 6-hour flow rate test period,
install the flow rate reduction device and change the sampler flow rate
recording frequency to intervals of not more than 30 seconds. Reset the
sampler to start a new sample collection period. Manually restrict the
sampler flow rate such that the sampler flow rate is decreased slowly
over several minutes to a flow rate slightly less than the flow rate
cut-off value (15.0 L/min). Maintain this flow rate for at least 2.0
minutes or until the sampler stops the sample flow automatically.
Manually terminate the sample period, if the sampler has not terminated
it automatically.
(g) Test results. At the completion of the test, validate the test
conditions and determine the test results as follows:
(1) Mean sample flow rate. (i) From the certified measurements
(Q<INF>ref</INF>) of the test sampler flow rate obtained by use of the
flow rate meter, tabulate each flow rate measurement in units of L/min.
If ambient temperature and pressure corrections are necessary to
calculate volumetric flow rate, each measured flow rate shall be
corrected using its corresponding temperature and pressure measurement
values. Calculate the mean flow rate for the sample period
(Q<INF>ref,ave</INF>) as follows:

Equation 1
[GRAPHIC] [TIFF OMITTED] TR18JY97.063

where:
n equals the number of discrete certified flow rate measurements
over the 6-hour test period.

(ii)(A) Calculate the percent difference between this mean flow
rate value and the design value of 16.67 L/min, as follows:

Equation 2
[GRAPHIC] [TIFF OMITTED] TR18JY97.064

(B) To successfully pass the mean flow rate test, the percent
difference calculated in Equation 2 of this paragraph (g)(1)(ii) must
be within <plus-minus>5 percent.
(2) Sample flow rate regulation. (i) From the certified
measurements of the test sampler flow rate, calculate the sample
coefficient of variation (CV) of the discrete measurements as follows:

Equation 3
[GRAPHIC] [TIFF OMITTED] TR18JY97.065

(ii) To successfully pass the flow rate regulation test, the
calculated coefficient of variation for the certified flow rates must
not exceed 2 percent.

[[Page 38803]]

(3) Flow rate measurement accuracy. (i) Using the mean volumetric
flow rate reported by the candidate test sampler at the completion of
the 6-hour test period (Q<INF>ind,ave</INF>), determine the accuracy of
the reported mean flow rate as:

Equation 4
[GRAPHIC] [TIFF OMITTED] TR18JY97.066

(ii) To successfully pass the flow rate measurement accuracy test,
the percent difference calculated in Equation 4 of this paragraph
(g)(3) shall not exceed 2 percent.
(4) Flow rate coefficient of variation measurement accuracy. (i)
Using the flow rate coefficient of variation indicated by the candidate
test sampler at the completion of the 6-hour test (%CV<INF>ind</INF>),
determine the accuracy of this reported coefficient of variation as:

Equation 5
[GRAPHIC] [TIFF OMITTED] TR18JY97.067

(ii) To successfully pass the flow rate CV measurement accuracy
test, the absolute difference in values calculated in Equation 5 of
this paragraph (g)(4) must not exceed 0.3 (CV%).
(5) Flow rate cut-off. (i) Inspect the measurements of the sample
flow rate during the flow rate cut-off test and determine the time at
which the sample flow rate decreased to a value less than the cut-off
value specified in Table E-1 of this subpart. To pass this test, the
sampler must have automatically stopped the sample flow at least 30
seconds but not more than 90 seconds after the time at which the
sampler flow rate was determined to have decreased to a value less than
the cut-off value.
(ii) At the completion of the flow rate cut-off test, download the
archived data from the test sampler and verify that the sampler's
required Flow-out-of-spec and Incorrect sample period flag indicators
are properly set.

Sec. 53.54 Test for proper sampler operation following power
interruptions.

(a) Overview. (1) This test procedure is designed to test certain
performance parameters of the candidate sampler during a test period in
which power interruptions of various duration occur. The performance
parameters tested are:
(i) Proper flow rate performance of the sampler.
(ii) Accuracy of the sampler's average flow rate, CV, and sample
volume measurements.
(iii) Accuracy of the sampler's reported elapsed sampling time.
(iv) Accuracy of the reported time and duration of power
interruptions.
(2) This test shall be conducted during operation of the test
sampler over a continuous 6-hour test period during which the sampler's
flow rate shall be measured and recorded at intervals not to exceed 5
minutes. The performance parameters tested under this procedure, the
corresponding minimum performance specifications, and the applicable
test conditions are summarized in Table E-1 of this subpart. Each
performance parameter tested, as described or determined in the test
procedure, must meet or exceed the associated performance specification
to successfully pass this test.
(b) Required test equipment. (1) Flow rate meter, suitable for
measuring and recording the actual volumetric sample flow rate at the
sampler downtube, with a minimum range of 10 to 25 L/min, 2 percent
certified, NIST-traceable accuracy. Optional capability for continuous
(analog) recording capability or digital recording at intervals not to
exceed 5 minutes is recommended. While a flow meter which provides a
direct indication of volumetric flow rate is preferred for this test,
an alternative certified flow measurement device may be used as long as
appropriate volumetric flow rate corrections are made based on
measurements of actual ambient temperature and pressure conditions.
(2) Ambient air temperature sensor (if needed for volumetric
corrections to flow rate measurements), with a resolution of 0.1
deg.C, certified accurate to within 0.5 deg.C, and continuous (analog)
recording capability or digital recording at intervals not to exceed 5
minutes.
(3) Barometer (if needed for volumetric corrections to flow rate
measurements), range 600 mm Hg to 800 mm Hg, certified accurate to 2 mm
Hg, with continuous (analog) recording capability or digital recording
at intervals not to exceed 5 minutes.
(4) Flow measurement adaptor (40 CFR part 50, Appendix L, Figure L-
30) or equivalent adaptor to facilitate measurement of sample flow rate
at the sampler downtube.
(5) 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.
(6) Teflon sample filter, as specified in section 6 of 40 CFR part
50, Appendix L (if required).
(7) Time measurement system, accurate to within 10 seconds per day.
(c) Calibration of test measurement instruments. Submit
documentation showing evidence of appropriately recent calibration,
certification of calibration accuracy, and NIST-traceability (if
required) of all measurement instruments used in the tests. The
accuracy of flow rate meters shall be verified at the highest and
lowest pressures and temperatures used in the tests and shall be
checked at zero and at least one flow rate within <plus-minus>3 percent
of 16.7 L/min within 7 days prior to use for this test. 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.
(d) Test setup. (1) Setup of the sampler shall be performed as
required in this paragraph (d) and otherwise 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_2.5 samples. A
sample filter and (or) the device for creating an additional 55 mm Hg
pressure drop shall be installed for the duration of these tests. The
sampler's ambient temperature, ambient pressure, and flow measurement
systems shall all be calibrated per the sampler's operating manual
within 7 days prior to this test.
(2) The inlet of the candidate sampler shall be removed and the
flow measurement adaptor installed on the sample downtube. A leak check
as described in the sampler's operation or instruction manual shall be
conducted and must be properly passed before other tests are carried out.
(3) The inlet of the flow measurement adaptor shall be connected to
the outlet of the flow rate meter.
(e) Procedure. (1) Set up the sampler as specified in paragraph (d)
of this section and otherwise 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 6-hour
sample collection period at a convenient time.
(2) During the entire 6-hour operational flow rate portion of the
test, measure and record the sample flow rate with the flow rate meter
at intervals not to exceed 5 minutes. If ambient temperature and
pressure corrections are necessary to calculate volumetric flow rate,
ambient temperature and pressure shall be measured at the same
frequency as that of the certified flow rate measurements. Note and
record the actual start and stop times for the 6-hour flow rate test period.
(3) During the 6-hour test period, interrupt the AC line electrical
power to

[[Page 38804]]

the sampler 5 times, with durations of 20 seconds, 40 seconds, 2
minutes, 7 minutes, and 20 minutes (respectively), with not less than
10 minutes of normal electrical power supplied between each power
interruption. Record the hour and minute and duration of each power
interruption.
(4) At the end of the test, terminate the sample period (if not
automatically terminated by the sampler) and download all archived
instrument data from the test sampler.
(f) Test results. At the completion of the sampling period,
validate the test conditions and determine the test results as follows:
(1) Mean sample flow rate. (i) From the certified measurements
(Q<INF>ref</INF>) of the test sampler flow rate, tabulate each flow
rate measurement in units of L/min. If ambient temperature and pressure
corrections are necessary to calculate volumetric flow rate, each
measured flow rate shall be corrected using its corresponding
temperature and pressure measurement values. Calculate the mean flow
rate for the sample period (Q<INF>ref,ave</INF>) as follows:

Equation 6
[GRAPHIC] [TIFF OMITTED] TR18JY97.068

where:
n equals the number of discrete certified flow rate measurements
over the 6-hour test period, excluding flow rate values obtained
during periods of power interruption.

(ii)(A) Calculate the percent difference between this mean flow
rate value and the design value of 16.67 L/min, as follows:

Equation 7
[GRAPHIC] [TIFF OMITTED] TR18JY97.069

(B) To successfully pass this test, the percent difference
calculated in Equation 7 of this paragraph (f)(1)(ii) must be within
<plus-minus>5 percent.
(2) Sample flow rate regulation. (i) From the certified
measurements of the test sampler flow rate, calculate the sample
coefficient of variation of the discrete measurements as follows:

Equation 8
[GRAPHIC] [TIFF OMITTED] TR18JY97.070

(ii) To successfully pass this test, the calculated coefficient of
variation for the certified flow rates must not exceed 2 percent.
(3) Flow rate measurement accuracy. (i) Using the mean volumetric
flow rate reported by the candidate test sampler at the completion of
the 6-hour test (Q<INF>ind,ave</INF>), determine the accuracy of the
reported mean flow rate as:

Equation 9
[GRAPHIC] [TIFF OMITTED] TR18JY97.071

(ii) To successfully pass this test, the percent difference
calculated in Equation 9 of this paragraph (f)(3) shall not exceed 2
percent.
(4) Flow rate CV measurement accuracy. (i) Using the flow rate
coefficient of variation indicated by the candidate test sampler at the
completion of the 6-hour test (%CV<INF>ind</INF>), determine the
accuracy of the reported coefficient of variation as:

Equation 10
[GRAPHIC] [TIFF OMITTED] TR18JY97.072

(ii) To successfully pass this test, the absolute difference in
values calculated in Equation 10 of this paragraph (f)(4) must not
exceed 0.3 (CV%).
(5) Verify that the sampler properly provided a record and visual
display of the correct year, month, day-of-month, hour, and minute with
an accuracy of <plus-minus> 2 minutes, of the start of each power
interruption of duration greater than 60 seconds.
(6) Calculate the actual elapsed sample time, excluding the periods
of electrical power interruption. Verify that the elapsed sample time
reported by the sampler is accurate to within <plus-minus> 20 seconds
for the 6-hour test run.
(7) Calculate the sample volume as Q<INF>ref,ave</INF> the sample
time, excluding periods of power interruption. Verify that the sample
volume reported by the sampler is within 2 percent of the calculated
sample volume to successfully pass this test.
(8) Inspect the downloaded instrument data from the test sampler
and verify that all data are consistent with normal operation of the
sampler.

Sec. 53.55 Test for effect of variations in power line voltage and
ambient temperature.

(a) Overview. (1) This test procedure is a combined procedure to
test various performance parameters under variations in power line
voltage and ambient temperature. Tests shall be conducted in a
temperature controlled environment over four 6-hour time periods during
which reference temperature and flow rate measurements shall be made at
intervals not to exceed 5 minutes. Specific parameters to be evaluated
at line voltages of 105 and 125 volts and temperatures of -20 deg.C
and +40 deg.C are as follows:
(i) Sample flow rate.
(ii) Flow rate regulation.
(iii) Flow rate measurement accuracy.
(iv) Coefficient of variability measurement accuracy.
(v) Ambient air temperature measurement accuracy.
(vi) Proper operation of the sampler when exposed to power line
voltage and ambient temperature extremes.
(2) The performance parameters tested under this procedure, the
corresponding minimum performance specifications, and the applicable
test conditions are summarized in Table E-1 of this subpart. Each
performance parameter tested, as described or determined in the test
procedure, must meet or exceed the associated performance specification
given. The candidate sampler must meet all specifications for the
associated PM_2.5 method to pass this test procedure.
(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 temperatures at -20 deg.C and +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 these temperatures
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.
(2) Variable voltage AC power transformer, range 100 Vac to 130
Vac, with sufficient current capacity to operate the test sampler
continuously under the test conditions.
(3) Flow rate meter, suitable for measuring and recording the
actual volumetric sample flow rate at the sampler downtube, with a
minimum range of 10 to 25 actual L/min, 2 percent certified, NIST-
traceable accuracy. Optional capability for continuous (analog)
recording capability or digital recording at intervals not to exceed 5
minutes is recommended. While a flow

[[Page 38805]]

meter which provides a direct indication of volumetric flow rate is
preferred for this test, an alternative certified flow measurement
device may be used as long as appropriate volumetric flow rate
corrections are made based on measurements of actual ambient
temperature and pressure conditions.
(4) Ambient air temperature recorder, range -30 deg.C to +50
deg.C, with a resolution of 0.1 deg.C and certified accurate to within
0.5 deg.C. Ambient air temperature measurements must be made using
continuous (analog) recording capability or digital recording at
intervals not to exceed 5 minutes.
(5) Barometer, range 600 mm Hg to 800 mm Hg, certified accurate to
2 mm Hg. If the certified flow rate meter does not provide direct
volumetric flow rate readings, ambient pressure measurements must be
made using continuous (analog) recording capability or digital
recording at intervals not to exceed 5 minutes.
(6) Flow measurement adaptor (40 CFR part 50, Appendix L, Figure L-
30) or equivalent adaptor to facilitate measurement of sampler flow
rate at the sampler downtube.
(7) 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.
(8) AC RMS voltmeter, accurate to 1.0 volt.
(9) Teflon sample filter, as specified in section 6 of 40 CFR part
50, Appendix L (if required).
(d) Calibration of test measurement instruments. Submit
documentation showing evidence of appropriately recent calibration,
certification of calibration accuracy, and NIST-traceability (if
required) of all measurement instruments used in the tests. The
accuracy of flow rate meters shall be verified at the highest and
lowest pressures and temperatures used in the tests and shall be
checked at zero and at least one flow rate within <plus-minus>3 percent
of 16.7 L/min within 7 days prior to use for this test. 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) Setup of the sampler shall be performed as
required in this paragraph (e) and otherwise 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
the temperature-controlled chamber in its normal configuration for
collecting PM_2.5 samples. A sample filter and (or) the
device for creating an additional 55 mm Hg pressure drop shall be
installed for the duration of these tests. The sampler's ambient
temperature, ambient pressure, and flow measurement systems shall all
be calibrated per the sampler's operating manual within 7 days prior to
this test.
(2) The inlet of the candidate sampler shall be removed and the
flow measurement adaptor installed on the sampler's downtube. A leak
check as described in the sampler's operation or instruction manual
shall be conducted and must be properly passed before other tests are
carried out.
(3) The inlet of the flow measurement adaptor shall be connected to
the outlet of the flow rate meter.
(4) 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 vicinity of the candidate sampler without being unduly
affected by the chamber's air temperature control system.
(f) Procedure. (1) Set up the sampler as specified in paragraph (e)
of this section and otherwise prepare the sampler for normal sample
collection operation as directed in the sampler's operation or
instruction manual.
(2) The test shall consist of four test runs, one at each of the
following conditions of chamber temperature and electrical power line
voltage (respectively):
(i) -20 deg.C <plus-minus>2 deg.C and 105 <plus-minus>1 Vac.
(ii) -20 deg.C <plus-minus>2 deg.C and 125 <plus-minus>1 Vac.
(iii) +40 deg.C <plus-minus>2 deg.C and 105 <plus-minus>1 Vac.
(iv) +40 deg.C <plus-minus>2 deg.C and 125 <plus-minus>1 Vac.
(3) For each of the four test runs, set the selected chamber
temperature and power line voltage for the test run. Upon achieving
each temperature setpoint in the chamber, the candidate sampler and
flow meter shall be thermally equilibrated for a period of at least 2
hours prior to the test run. Following the thermal conditioning time,
set the sampler to automatically start a 6-hour sample collection
period at a convenient time.
(4) During each 6-hour test period:
(i) Measure and record the sample flow rate with the flow rate
meter at intervals not to exceed 5 minutes. If ambient temperature and
pressure corrections are necessary to calculate volumetric flow rate,
ambient temperature and pressure shall be measured at the same
frequency as that of the certified flow rate measurements. Note and
record the actual start and stop times for the 6-hour flow rate test period.
(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 at intervals not to exceed 5 minutes.
(iii) Measure the power line voltage to the sampler at intervals
not greater than 1 hour.
(5) At the end of each test run, terminate the sample period (if
not automatically terminated by the sampler) and download all archived
instrument data from the test sampler.
(g) Test results. For each of the four test runs, examine the
chamber temperature measurements and the power line voltage
measurements. Verify that the temperature and line voltage met the
requirements specified in paragraph (f) of this section at all times
during the test run. If not, the test run is not valid and must be
repeated. Determine the test results as follows:
(1) Mean sample flow rate. (i) From the certified measurements
(Q<INF>ref</INF>) of the test sampler flow rate, tabulate each flow
rate measurement in units of L/min. If ambient temperature and pressure
corrections are necessary to calculate volumetric flow rate, each
measured flow rate shall be corrected using its corresponding
temperature and pressure measurement values. Calculate the mean flow
rate for each sample period (Q<INF>ref,ave</INF>) as follows:

Equation 11
[GRAPHIC] [TIFF OMITTED] TR18JY97.073

where:
n equals the number of discrete certified flow rate measurements
over each 6-hour test period.

(ii)(A) Calculate the percent difference between this mean flow
rate value and the design value of 16.67 L/min, as follows:

Equation 12
[GRAPHIC] [TIFF OMITTED] TR18JY97.074

(B) To successfully pass this test, the percent difference
calculated in Equation 12 of this paragraph (g)(1)(ii) must be within
<plus-minus>5 percent for each test run.
(2) Sample flow rate regulation. (i) From the certified
measurements of the test sampler flow rate, calculate the sample
coefficient of variation of the discrete measurements as follows:

[[Page 38806]]

Equation 13
[GRAPHIC] [TIFF OMITTED] TR18JY97.075

(ii) To successfully pass this test, the calculated coefficient of
variation for the certified flow rates must not exceed 2 percent.
(3) Flow rate measurement accuracy. (i) Using the mean volumetric
flow rate reported by the candidate test sampler at the completion of
each 6-hour test (Q<INF>ind,ave</INF>), determine the accuracy of the
reported mean flow rate as:

Equation 14
[GRAPHIC] [TIFF OMITTED] TR18JY97.076

(ii) To successfully pass this test, the percent difference
calculated in Equation 14 of this paragraph (g)(3) shall not exceed 2
percent for each test run.
(4) Flow rate coefficient of variation measurement accuracy. (i)
Using the flow rate coefficient of variation indicated by the candidate
test sampler (%CV<INF>ind</INF>), determine the accuracy of the
reported coefficient of variation as:

Equation 15
[GRAPHIC] [TIFF OMITTED] TR18JY97.077

(ii) To successfully pass this test, the absolute difference
calculated in Equation 15 of this paragraph (g)(4) must not exceed 0.3
(CV%) for each test run.
(5) Ambient temperature measurement accuracy. (i) Calculate the
absolute value of the difference between the mean ambient air
temperature indicated by the test sampler and the mean ambient
(chamber) air temperature measured with the ambient air temperature
recorder as:

Equation 16
[GRAPHIC] [TIFF OMITTED] TR18JY97.078

where:
T<INF>ind,ave</INF> = mean ambient air temperature indicated by the
test sampler, deg.C; and
T<INF>ref,ave</INF> = mean ambient air temperature measured by the
reference temperature instrument, deg.C.

(ii) The calculated temperature difference must be less than 2
deg.C for each test run.
(6) Sampler functionality. To pass the sampler functionality test,
the following two conditions must both be met for each test run:
(i) The sampler must not shutdown during any portion of the 6-hour test.
(ii) An inspection of the downloaded data from the test sampler
verifies that all the data are consistent with normal operation of the
sampler.

Sec. 53.56 Test for effect of variations in ambient pressure.

(a) Overview. (1) This test procedure is designed to test various
sampler performance parameters under variations in ambient (barometric)
pressure. Tests shall be conducted in a pressure-controlled environment
over two 6-hour time periods during which reference pressure and flow
rate measurements shall be made at intervals not to exceed 5 minutes.
Specific parameters to be evaluated at operating pressures of 600 and
800 mm Hg are as follows:
(i) Sample flow rate.
(ii) Flow rate regulation.
(iii) Flow rate measurement accuracy.
(iv) Coefficient of variability measurement accuracy.
(v) Ambient pressure measurement accuracy.
(vi) Proper operation of the sampler when exposed to ambient
pressure extremes.
(2) The performance parameters tested under this procedure, the
corresponding minimum performance specifications, and the applicable
test conditions are summarized in Table E-1 of this subpart. Each
performance parameter tested, as described or determined in the test
procedure, must meet or exceed the associated performance specification
given. The candidate sampler must meet all specifications for the
associated PM_2.5 method to pass this test procedure.
(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) Hypobaric chamber or other
pressure-controlled environment or environments, capable of obtaining
and maintaining pressures at 600 mm Hg and 800 mm Hg required for the
test with an accuracy of 5 mm Hg. Henceforth, where the test procedures
specify a test or environmental chamber, an alternative pressure-
controlled environmental area or areas may be substituted, provided the
test pressure requirements are met. Means for simulating ambient
pressure using a closed-loop sample air system may also be approved for
this test; such a proposed method for simulating the test pressure
conditions may be described and submitted to EPA at the address given
in Sec. 53.4(a) prior to conducting the test for a specific individual
determination of acceptability.
(2) Flow rate meter, suitable for measuring and recording the
actual volumetric sampler flow rate at the sampler downtube, with a
minimum range of 10 to 25 L/min, 2 percent certified, NIST-traceable
accuracy. Optional capability for continuous (analog) recording
capability or digital recording at intervals not to exceed 5 minutes is
recommended. While a flow meter which provides a direct indication of
volumetric flow rate is preferred for this test, an alternative
certified flow measurement device may be used as long as appropriate
volumetric flow rate corrections are made based on measurements of
actual ambient temperature and pressure conditions.
(3) Ambient air temperature recorder (if needed for volumetric
corrections to flow rate measurements) with a range -30 deg.C to +50
deg.C, certified accurate to within 0.5 deg.C. If the certified flow
meter does not provide direct volumetric flow rate readings, ambient
temperature measurements must be made using continuous (analog)
recording capability or digital recording at intervals not to exceed 5
minutes.
(4) Barometer, range 600 mm Hg to 800 mm Hg, certified accurate to
2 mm Hg. Ambient air pressure measurements must be made using
continuous (analog) recording capability or digital recording at
intervals not to exceed 5 minutes.
(5) Flow measurement adaptor (40 CFR part 50, Appendix L, Figure L-
30) or equivalent adaptor to facilitate measurement of sampler flow
rate at the sampler downtube.
(6) 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.
(7) Teflon sample filter, as specified in section 6 of 40 CFR part
50, Appendix L (if required).
(d) Calibration of test measurement instruments. Submit
documentation showing evidence of appropriately recent calibration,
certification of calibration accuracy, and NIST-traceability (if
required) of all measurement instruments used in the tests. The
accuracy of flow rate meters shall be verified at the highest and
lowest pressures and temperatures used in the tests and shall be
checked at zero and at least one flow rate within <plus-minus>3 percent
of 16.7 L/min within 7 days prior to use for this test. Where an
instrument's measurements are to be

[[Page 38807]]

recorded with an analog recording device, the accuracy of the entire
instrument-recorder system shall be calibrated or verified.
(e) Test setup. (1) Setup of the sampler shall be performed as
required in this paragraph (e) and otherwise 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
the pressure-controlled chamber in its normal configuration for
collecting PM_2.5 samples. A sample filter and (or) the
device for creating an additional 55 mm Hg pressure drop shall be
installed for the duration of these tests. The sampler's ambient
temperature, ambient pressure, and flow measurement systems shall all
be calibrated per the sampler's operating manual within 7 days prior to
this test.
(2) The inlet of the candidate sampler shall be removed and the
flow measurement adaptor installed on the sampler's downtube. A leak
check as described in the sampler's operation or instruction manual
shall be conducted and must be properly passed before other tests are
carried out.
(3) The inlet of the flow measurement adaptor shall be connected to
the outlet of the flow rate meter.
(4) The barometer shall be installed in the test chamber such that
it will accurately measure the air pressure to which the candidate
sampler is subjected.
(f) Procedure. (1) Set up the sampler as specified in paragraph (e)
of this section and otherwise prepare the sampler for normal sample
collection operation as directed in the sampler's operation or
instruction manual.
(2) The test shall consist of two test runs, one at each of the
following conditions of chamber pressure:
(i) 600 mm Hg.
(ii) 800 mm Hg.
(3) For each of the two test runs, set the selected chamber
pressure for the test run. Upon achieving each pressure setpoint in the
chamber, the candidate sampler shall be pressure-equilibrated for a
period of at least 30 minutes prior to the test run. Following the
conditioning time, set the sampler to automatically start a 6-hour
sample collection period at a convenient time.
(4) During each 6-hour test period:
(i) Measure and record the sample flow rate with the flow rate
meter at intervals not to exceed 5 minutes. If ambient temperature and
pressure corrections are necessary to calculate volumetric flow rate,
ambient temperature and pressure shall be measured at the same
frequency as that of the certified flow rate measurements. Note and
record the actual start and stop times for the 6-hour flow rate test period.
(ii) Determine and record the ambient (chamber) pressure indicated
by the sampler and the corresponding ambient (chamber) pressure
measured by the barometer specified in paragraph (c)(4) of this section
at intervals not to exceed 5 minutes.
(5) At the end of each test period, terminate the sample period (if
not automatically terminated by the sampler) and download all archived
instrument data from the test sampler.
(g) Test results. For each of the two test runs, examine the
chamber pressure measurements. Verify that the pressure met the
requirements specified in paragraph (f) of this section at all times
during the test. If not, the test run is not valid and must be
repeated. Determine the test results as follows:
(1) Mean sample flow rate. (i) From the certified measurements
(Q<INF>ref</INF>) of the test sampler flow rate, tabulate each flow
rate measurement in units of L/min. If ambient temperature and pressure
corrections are necessary to calculate volumetric flow rate, each
measured flow rate shall be corrected using its corresponding
temperature and pressure measurement values. Calculate the mean flow
rate for the sample period (Q<INF>ref,ave</INF>) as follows:

Equation 17
[GRAPHIC] [TIFF OMITTED] TR18JY97.079

where:
n equals the number of discrete certified flow measurements over the
6-hour test period.

(ii)(A) Calculate the percent difference between this mean flow
rate value and the design value of 16.67 L/min, as follows:

Equation 18
[GRAPHIC] [TIFF OMITTED] TR18JY97.080

(B) To successfully pass this test, the percent difference
calculated in Equation 18 of this paragraph (g)(1) must be within
<plus-minus>5 percent for each test run.
(2) Sample flow rate regulation. (i) From the certified
measurements of the test sampler flow rate, calculate the sample
coefficient of variation of the discrete measurements as follows:

Equation 19
[GRAPHIC] [TIFF OMITTED] TR18JY97.081

(ii) To successfully pass this test, the calculated coefficient of
variation for the certified flow rates must not exceed 2 percent.
(3) Flow rate measurement accuracy. (i) Using the mean volumetric
flow rate reported by the candidate test sampler at the completion of
each 6-hour test (Q<INF>ind,ave</INF>), determine the accuracy of the
reported mean flow rate as:

Equation 20
[GRAPHIC] [TIFF OMITTED] TR18JY97.082

(ii) To successfully pass this test, the percent difference
calculated in Equation 20 of this paragraph (g)(3) shall not exceed 2
percent for each test run.
(4) Flow rate CV measurement accuracy. (i) Using the flow rate
coefficient of variation indicated by the candidate test sampler at the
completion of the 6-hour test (%CV<INF>ind</INF>), determine the
accuracy of the reported coefficient of variation as:

Equation 21
[GRAPHIC] [TIFF OMITTED] TR18JY97.083

(ii) To successfully pass this test, the absolute difference in
values calculated in Equation 21 of this paragraph (g)(4) must not
exceed 0.3 (CV%) for each test run.
(5) Ambient pressure measurement accuracy. (i) Calculate the
absolute difference between the mean ambient air pressure indicated by
the test sampler and the ambient (chamber) air pressure measured with
the reference barometer as:

Equation 22
[GRAPHIC] [TIFF OMITTED] TR18JY97.084

[[Page 38808]]

where:
P<INF>ind,ave</INF> = mean ambient pressure indicated by the test
sampler, mm Hg; and
P<INF>ref,ave</INF> = mean barometric pressure measured by the
reference barometer, mm Hg.

(ii) The calculated pressure difference must be less than 10 mm Hg
for each test run to pass the test.
(6) Sampler functionality. To pass the sampler functionality test,
the following two conditions must both be met for each test run:
(i) The sampler must not shut down during any part of the 6-hour
tests; and
(ii) An inspection of the downloaded data from the test sampler
verifies that all the data are consistent with normal operation of the
sampler.

Sec. 53.57 Test for filter temperature control during sampling and
post-sampling periods.

(a) Overview. This test is intended to measure the candidate
sampler's ability to prevent excessive overheating of the
PM_2.5 sample collection filter (or filters) under conditions
of elevated solar insolation. The test evaluates radiative effects on
filter temperature during a 4-hour period of active sampling as well as
during a subsequent 4-hour non-sampling time period prior to filter
retrieval. Tests shall be conducted in an environmental chamber which
provides the proper radiant wavelengths and energies to adequately
simulate the sun's radiant effects under clear conditions at sea level.
For additional guidance on conducting solar radiative tests under
controlled conditions, consult military standard specification 810-E
(Reference 6 in Appendix A of this subpart). The performance parameters
tested under this procedure, the corresponding minimum performance
specifications, and the applicable test conditions are summarized in
Table E-1 of this subpart. Each performance parameter tested, as
described or determined in the test procedure, must meet or exceed the
associated performance specification to successfully pass this test.
(b) Technical definition. Filter temperature control during
sampling is the ability of a sampler to maintain the temperature of the
particulate matter sample filter within the specified deviation (5
deg.C) from ambient temperature during any active sampling period.
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 from
the end of active sample collection of the PM_2.5 sample by
the sampler until the filter is retrieved from the sampler for
laboratory analysis.
(c) Required test equipment. (1) Environmental chamber providing
the means, such as a bank of solar-spectrum lamps, for generating or
simulating thermal radiation in approximate spectral content and
intensity equivalent to solar insolation of 1000 <plus-minus> 50 W/
m2 inside the environmental chamber. To properly simulate
the sun's radiative effects on the sampler, the solar bank must provide
the spectral energy distribution and permitted tolerances specified in
Table E-2 of this subpart. The solar radiation source area shall be
such that the width of the candidate sampler shall not exceed one-half
the dimensions of the solar bank. The solar bank shall be located a
minimum of 76 cm (30 inches) from any surface of the candidate sampler.
To meet requirements of the solar radiation tests, the chamber's
internal volume shall be a minimum of 10 times that of the volume of
the candidate sampler. Air velocity in the region of the sampler must
be maintained continuously during the radiative tests at 2.0
<plus-minus> 0.5 m/sec.
(2) Ambient air temperature recorder, range -30 deg.C to +50
deg.C, with a resolution of 0.1 deg.C and certified accurate to within
0.5 deg.C. Ambient air temperature measurements must be made using
continuous (analog) recording capability or digital recording at
intervals not to exceed 5 minutes.
(3) Flow measurement adaptor (40 CFR part 50, Appendix L, Figure L-
30) or equivalent adaptor to facilitate measurement of sampler flow
rate at the sampler downtube.
(4) Miniature temperature sensor(s), 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; with a resolution of 0.1 deg.C, 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) Solar radiometer, to measure the intensity of the simulated
solar radiation in the test environment, range of 0 to approximately
1500 W/m2. Optional capability for continuous (analog)
recording or digital recording at intervals not to exceed 5 minutes is
recommended.
(6) Sample filter or filters, as specified in section 6 of 40 CFR
part 50, Appendix L.
(d) Calibration of test measurement instruments. Submit
documentation showing evidence of appropriately recent calibration,
certification of calibration accuracy, and NIST-traceability (if
required) of all measurement instruments used in the tests. The
accuracy of flow rate meters shall be verified at the highest and
lowest pressures and temperatures used in the tests and shall be
checked at zero and at least one flow rate within <plus-minus>3 percent
of 16.7 L/min within 7 days prior to use for this test. 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) Setup of the sampler shall be performed as
required in this paragraph (e) and otherwise 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
the solar radiation environmental chamber in its normal configuration
for collecting PM_2.5 samples (with the inlet installed). The
sampler's ambient and filter temperature measurement systems shall be
calibrated per the sampler's operating manual within 7 days prior to
this test. A sample filter shall be installed for the duration of this
test. For sequential samplers, a sample filter shall also be installed
in each available sequential channel or station intended for collection
of a sequential sample (or at least 5 additional filters for magazine-
type sequential samplers) as directed by the sampler's operation or
instruction manual.
(2) The miniature temperature sensor shall be temporarily 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 such that no external or
internal air leakage is created by the sensor installation. The
sensor's dimensions and installation shall be selected to minimize
temperature measurement uncertainties due to thermal conduction along
the sensor mounting structure or sensor conductors. For sequential
samplers, similar temperature sensors shall also be temporarily
installed in the test sampler to monitor the temperature 1 cm from the
center of each filter stored in the sampler for sequential sample operation.
(3) 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 deg. and 45 deg. from vertical. The
intensity of the radiation received by all sampler

[[Page 38809]]

surfaces that receive direct radiation shall average 1000 <plus-minus>
50 W/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 shield) receives full, direct radiation as it would or
could during normal outdoor installation. Also, the temperature sensor
must not be shielded or shaded from the radiation by a sampler part in
a way that would not occur at other normal insolation angles or
directions.
(4) The solar radiometer shall be installed in a location where it
measures thermal radiation that is generally representative of the
average thermal radiation intensity that the upper portion of the
sampler and sampler inlet receive. The solar radiometer shall be
oriented so that it measures the radiation in a plane perpendicular to
its angle of incidence.
(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 source that may be present inside the test chamber.
(f) Procedure. (1) Set up the sampler as specified in paragraph (e)
of this section and otherwise prepare the sampler for normal sample
collection operation as directed in the sampler's operation or
instruction manual.
(2) Remove the inlet of the candidate test sampler and install the
flow measurement adaptor on the sampler's downtube. Conduct a leak
check as described in the sampler's operation or instruction manual.
The leak test must be properly passed before other tests are carried out.
(3) Remove the flow measurement adaptor from the downtube and re-
install the sampling inlet.
(4) Activate the solar radiation source and verify that the
resulting energy distribution prescribed in Table E-2 of this subpart
is achieved.
(5) Program the test sampler to conduct a single sampling run of 4
continuous hours. During the 4-hour sampling run, measure and record
the radiant flux, ambient temperature, and filter temperature (all
filter temperatures for sequential samplers) at intervals not to exceed
5 minutes.
(6) At the completion of the 4-hour sampling phase, terminate the
sample period, if not terminated automatically by the sampler. Continue
to measure and record the radiant flux, ambient temperature, and filter
temperature or temperatures for 4 additional hours at intervals not to
exceed 5 minutes. At the completion of the 4-hour post-sampling period,
discontinue the measurements and turn off the solar source.
(7) Download all archived sampler data from the test run.
(g) Test results. Chamber temperature control. Examine the
continuous record of the chamber radiant flux and verify that the flux
met the requirements specified in Table E-2 of this subpart at all
times during the test. If not, the entire test is not valid and must be
repeated.
(1) Filter temperature measurement accuracy. (i) For each 4-hour
test period, calculate the absolute value of the difference between the
mean filter temperature indicated by the sampler (active filter) and
the mean filter temperature measured by the reference temperature
sensor installed within 1 cm downstream of the (active) filter as:

Equation 23
[GRAPHIC] [TIFF OMITTED] TR18JY97.085

where:
T<INF>ind,filter</INF> = mean filter temperature indicated by the
test sampler, deg.C; and
T<INF>ref,filter</INF> = mean filter temperature measured by the
reference temperature sensor, deg.C.

(ii) To successfully pass the indicated filter temperature accuracy
test, the calculated difference between the measured means
(T<INF>diff,filter</INF>) must not exceed 2 deg.C for each 4-hour test
period.
(2) Ambient temperature measurement accuracy. (i) For each 4-hour
test period, calculate the absolute value of the difference between the
mean ambient air temperature indicated by the test sampler and the mean
ambient air temperature measured by the reference ambient air
temperature recorder as:

Equation 24
[GRAPHIC] [TIFF OMITTED] TR18JY97.086

where:
T<INF>ind,ambient</INF> = mean ambient air temperature indicated by
the test sampler, deg.C; and
T<INF>ref,ambient</INF> = mean ambient air temperature measured by
the reference ambient air temperature recorder, deg.C.

(ii) To successfully pass the indicated ambient temperature
accuracy test, the calculated difference between the measured means
(T<INF>diff,ambient</INF>) must not exceed 2 deg.C for each 4-hour
test period.
(3) Filter temperature control accuracy. (i) For each temperature
measurement interval over each 4-hour test period, calculate the
difference between the filter temperature indicated by the reference
temperature sensor and the ambient temperature indicated by the test
sampler as:

Equation 25
[GRAPHIC] [TIFF OMITTED] TR18JY97.087

(ii) Tabulate and inspect the calculated differences as a function
of time. To successfully pass the indicated filter temperature control
test, the calculated difference between the measured values must not
exceed 5 deg.C for any consecutive intervals covering more than a 30-
minute time period.
(iii) For sequential samplers, repeat the test calculations for
each of the stored sequential sample filters. All stored filters must
also meet the 5 deg.C temperature control test.

Sec. 53.58 Operational field precision and blank 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_2.5 are made at a test site with all of the samplers and
then compared to determine replicate precision. Candidate sequential
samplers are also subject to a test for possible deposition of
particulate matter on inactive filters during a period of storage in
the sampler. 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 (described in 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. (1) Field precision is defined as the
standard deviation or relative standard deviation of a set of
PM_2.5 measurements obtained concurrently with three or more
collocated samplers in actual ambient air field operation.
(2) Storage deposition is defined as the mass of material
inadvertently deposited on a sample filter that is stored in a
sequential sampler either prior to or subsequent to the active sample
collection period.
(c) Test site. Any outdoor test site having PM_2.5
concentrations that are reasonably uniform over the test area and that
meet the minimum level requirement of paragraph (g)(2) of this section
is acceptable for this test.
(d) Required facilities and equipment. (1) An appropriate test site
and suitable

[[Page 38810]]

electrical power to accommodate three test samplers are required.
(2) Teflon sample filters, as specified in section 6 of 40 CFR part
50, Appendix L, conditioned and preweighed as required by section 8 of
40 CFR part 50, Appendix L, as needed for the test samples.
(e) Test setup. (1) Three identical test samplers shall be
installed at the test site in their normal configuration for collecting
PM_2.5 samples in accordance with the instructions in the
associated manual referred to in Sec. 53.4(b)(3) and should be in
accordance with applicable supplemental guidance provided in Reference
3 in Appendix A of this subpart. The test samplers' 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 the spatial and wind directional effects
on sample collection of one sampler on any other sampler.
(2) Each test sampler shall be successfully 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 subpart.
(f) Test procedure. (1) Install a conditioned, preweighed filter in
each test sampler and otherwise prepare each sampler for normal sample
collection. Set identical sample collection start and stop times for
each sampler. For sequential samplers, install a conditioned,
preweighed specified filter in each available channel or station
intended for automatic sequential sample filter collection (or at least
5 additional filters for magazine-type sequential samplers), as
directed by the sampler's operation or instruction manual. Since the
inactive sequential channels are used for the storage deposition part
of the test, they may not be used to collect the active
PM_2.5 test samples.
(2) Collect either a 24-hour or a 48-hour atmospheric
PM_2.5 sample simultaneously with each of the three test
samplers.
(3) Following sample collection, retrieve the collected sample from
each sampler. For sequential samplers, retrieve the additional stored
(blank, unsampled) filters after at least 5 days (120 hours) storage in
the sampler if the active samples are 24-hour samples, or after at
least 10 days (240 hours) if the active samples are 48-hour samples.
(4) Determine the measured PM_2.5 mass concentration for
each sample in accordance with the applicable procedures prescribed for
the candidate method in Appendix L, 40 CFR part 50 of this chapter, in
the associated manual referred to in Sec. 53.4(b)(3) and in accordance
with supplemental guidance in Reference 2 in Appendix A of this
subpart. For sequential samplers, also similarly determine the storage
deposition as the net weight gain of each blank, unsampled filter after
the 5-day (or 10-day) period of storage in the sampler.
(5) Repeat this procedure to obtain a total of 10 sets of any
combination of 24-hour or 48-hour PM_2.5 measurements over 10
test periods. For sequential samplers, repeat the 5-day (or 10-day)
storage test of additional blank filters once for a total of two sets
of blank filters.
(g) Calculations. (1) Record the PM_2.5 concentration for
each test sampler for each test period as C<INF>i,j</INF>, where i is
the sampler number (i=1,2,3) and j is the test period (j=1,2, . . . 10).
(2)(i) For each test period, calculate and record the average of
the three measured PM_2.5 concentrations as C<INF>j</INF>
where j is the test period:

Equation 26
[GRAPHIC] [TIFF OMITTED] TR18JY97.088

(ii) If C<INF>ave,j</INF> < 10 <greek-m>g/m3 for any
test period, data from that test period are unacceptable, and an
additional sample collection set must be obtained to replace the
unacceptable data.
(3)(i) Calculate and record the precision for each of the 10 test
days as:

Equation 27
[GRAPHIC] [TIFF OMITTED] TR18JY97.089

(ii) If C<INF>ave,j</INF> is below 40 <greek-m>g/m3 for
24-hour measurements or below 30 <greek-m>g/m3 for 48-hour
measurements; or

Equation 28
[GRAPHIC] [TIFF OMITTED] TR18JY97.090

(iii) If C<INF>ave,j</INF> 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. (1) The candidate method passes the precision
test if all 10 P<INF>j</INF> or RP<INF>j</INF> values meet the
specifications in Table E-1 of this subpart.
(2) The candidate sequential sampler passes the blank filter
storage deposition test if the average net storage deposition weight
gain of each set of blank filters (total of the net weight gain of each
blank filter divided by the number of filters in the set) from each
test sampler (six sets in all) is less than 50 <greek-m>g.

Sec. 53.59 Aerosol transport test for Class I equivalent method samplers.

(a) Overview. This test is intended to verify adequate aerosol
transport through any modified or air flow splitting components that
may be used in a Class I candidate equivalent method sampler such as
may be necessary to achieve sequential sampling capability. This test
is applicable to all Class I candidate samplers in which the aerosol
flow path (the flow path through which sample air passes upstream of
sample collection filter) differs from that specified for reference
method samplers as specified in 40 CFR part 50, Appendix L. 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 a laboratory challenge aerosol which penetrates to the active sample
filter of the candidate equivalent method sampler.
(2) The active sample filter is the exclusive filter through which
sample air is flowing during performance of this test.
(3) A no-flow filter is a sample filter through which no sample air
is intended to flow during performance of this test.
(4) A channel is any of two or more flow paths that the aerosol may
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 in some way from that specified for a reference method
sampler in 40 CFR part 50, Appendix L, such as a device or means to
allow or cause the aerosol to be routed to one of several channels.
(c) Required facilities and test equipment. (1) Aerosol generation
system, as specified in Sec. 53.62(c)(2).
(2) Aerosol delivery system, as specified in Sec. 53.64(c)(2).
(3) Particle size verification equipment, as specified in
Sec. 53.62(c)(3).
(4) Fluorometer, as specified in Sec. 53.62(c)(7).
(5) Candidate test 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)(2).
(6) Filters that are appropriate for use with fluorometric methods
(e.g., glass fiber).

[[Page 38811]]

(d) Calibration of test measurement instruments. Submit
documentation showing evidence of appropriately recent calibration,
certification of calibration accuracy, and NIST-traceability (if
required) of all measurement instruments used in the tests. The
accuracy of flow rate meters shall be verified at the highest and
lowest pressures and temperatures used in the tests and shall be
checked at zero and at least one flow rate within <plus-minus>3 percent
of 16.7 L/min within 7 days prior to use for this test. 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 test sampler shall have its inlet
and impactor or impactors removed. The lower end of the down tube shall
be reconnected to the filter holder, using an extension of the
downtube, if necessary. 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) The test particle delivery system shall be connected to the
sampler downtube so that the test aerosol is introduced at the top of
the downtube.
(f) Test procedure. (1) All surfaces of the added or modified
component or components which come in contact with the aerosol flow
shall be thoroughly washed with 0.01 N NaOH and then dried.
(2) Generate aerosol. (i) Generate aerosol composed of oleic acid
with a uranine fluorometric tag of 3 <plus-minus> 0.25 <greek-m>m
aerodynamic diameter using a vibrating orifice aerosol generator
according to conventions specified in Sec. 53.61(g).
(ii) Check for the presence of satellites and adjust the generator
to minimize their production.
(iii) Calculate the aerodynamic particle size using the operating
parameters of the vibrating orifice aerosol generator. The calculated
aerodynamic diameter must be 3 <plus-minus> 0.25 <greek-m>m aerodynamic
diameter.
(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 resulting measured fluorometric concentration for
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)</INF> where i = the
active channel number.
(6) Determine the quantity of material collected on each no-flow
filter using a calibrated fluorometer. Record the mass of fluorometric
material on each no-flow filter as M<INF>no-flow</INF>.
(7) Using 0.01 N NaOH, wash the surfaces of the added component or
components which contact the aerosol flow. Determine the quantity of
material collected using a calibrated fluorometer. Record the mass of
fluorometric material collected in the wash as M<INF>wash</INF>.
(8) Calculate the aerosol transport as:

Equation 29
[GRAPHIC] [TIFF OMITTED] TR18JY97.091

where:
i = the active channel number.

(9) Repeat paragraphs (f)(1) through (8) of this section for each
channel, making each channel in turn the exclusive active channel.
(g) Test results. The candidate Class I sampler passes the aerosol
transport test if T<INF>(i)</INF> is at least 97 percent for each
channel.
Tables to Subpart E of Part 53

Table E-1.--Summary of Test Requirements for Reference and Class I Equivalent Methods for PM<INF>2.5
----------------------------------------------------------------------------------------------------------------
Performance Part 50, Appendix
Subpart E Procedure Performance Test Specification Test Conditions L Reference
----------------------------------------------------------------------------------------------------------------
Sec. 53.52 Sampler leak check Sampler leak check External leakage: Controlled leak Sec. 7.4.6
test facility 80 mL/min, max flow rate of 80
Internal leakage: mL/min
80 mL/min, max
----------------------------------------------------------------------------------------------------------------
Sec. 53.53 Base flow rate test Sample flow rate: 1. 16.67 plus- (a) 6-hour normal Sec. 7.4.1
1. Mean minus 5%, L/min operational test Sec. 7.4.2
2. Regulation 2. 2%, max plus flow rate Sec. 7.4.3
3. Meas. accuracy 3. 2%, max cut-off test Sec. 7.4.4
4. CV accuracy 4. 0.3%, max (b) Nominal Sec. 7.4.5
5. Cut-off 5. Flow rate cut- conditions
off if flow rate (c) Additional 55
deviates more mm Hg pressure
than 10% from drop to simulate
design flow rate loaded filter
for >60 plus- (d) Variable flow
minus 30 seconds restriction used
for cut-off test
----------------------------------------------------------------------------------------------------------------
Sec. 53.54 Power interruption Sample flow rate: 1. 16.67 plus- (a) 6-hour normal Sec. 7.4.1
test 1. Mean minus 5%, L/min operational test Sec. 7.4.2
2. Regulation 2. 2%, max (b) Nominal Sec. 7.4.3
3. Meas. accuracy 3. 2%, max conditions Sec. 7.4.5
4. CV accuracy 4. 0.3%, max (c) Additional 55 Sec. 7.4.12
5. Occurrence time 5. plus-minus2 min mm Hg pressure Sec. 7.4.13
of power if >60 seconds drop to simulate Sec. 7.4.15.4
interruptions 6. plus-minus20 loaded filter Sec. 7.4.15.5
6. Elapsed sample seconds (d) 6 power
time 7. plus-minus2%, interruptions of
7. Sample volume max various durations
----------------------------------------------------------------------------------------------------------------

[[Page 38812]]

Sec. 53.55 Temperature and line Sample flow rate: 1. 16.67 plus- (a) 6-hour normal Sec. 7.4.1
voltage effect test 1. Mean minus 5%, L/min operational test Sec. 7.4.2
2. Regulation 2. 2 %, max (b) Nominal Sec. 7.4.3
3. Meas. accuracy 3. 2 %, max conditions Sec. 7.4.5
4. CV accuracy 4. 0.3 %, max (c) Additional 55 Sec. 7.4.8
5. Temperature 5. 2 deg.C mm Hg pressure Sec. 7.4.15.1
meas. accuracy drop to simulate
6. Proper loaded filter
operation (d) Ambient
temperature at -
20 and +40 deg.C
(e) Line voltage:
105 Vac to 125
Vac
----------------------------------------------------------------------------------------------------------------
Sec. 53.56 Barometric pressure Sample flow rate: 1. 16.67 plus- (a) 6-hour normal Sec. 7.4.1
effect test 1. Mean minus 5%, L/min operational test Sec. 7.4.2
2. Regulation 2. 2%, max (b) Nominal Sec. 7.4.3
3. Meas. accuracy 3. 2%, max conditions Sec. 7.4.5
4. CV accuracy 4. 0.3%, max (c) Additional 55 Sec. 7.4.9
5. Pressure meas. 5. 10 mm Hg mm Hg pressure
accuracy drop to simulate
6. Proper loaded filter
operation (d) Barometric
pressure at 600
and 800 mm Hg.
----------------------------------------------------------------------------------------------------------------
Sec. 53.57 Filter temperature 1. Filter temp 1. 2 deg.C (a) 4-hour Sec. 7.4.8
control test meas. accuracy 2. 2 deg.C simulated solar Sec. 7.4.10
2. Ambient temp. 3. Not more than 5 radiation, Sec. 7.4.11
meas. accuracy deg.C above sampling
3. Filter temp ambient temp. for (b) 4-hour
control accuracy, more than 30 min simulated solar
sampling and non- radiation, non-
sampling sampling
(c) Solar flux of
1000 W/m2
----------------------------------------------------------------------------------------------------------------
Sec. 53.58 Field precision test 1. Measurement 1. P<INF>j <2 <greek- (a) 3 collocated Sec. 5.1
precision m>g/m3 for conc. samplers at 1 Sec. 7.3.5
2. Storage <40 <greek-m>g/m3 site for at least Sec. 8
deposition test (24-hr) or <30 10 days Sec. 9
for sequential <greek-m>g/m3 (48- (b) PM<INF>2.5 conc.<ls- Sec. 10
samplers hr); or thn-eq>10 <greek-
RP<INF>j < 5% for conc. m>g/m3
>40 <greek-m>g/m3 (c) 24- or 48-hour
(24-hr) or >30 samples
<greek-m>g/m3 (48- (d) 5- or 10-day
hr) storage period
2. 50 <greek-m>g, for inactive
max weight gain stored filters
----------------------------------------------------------------------------------------------------------------

The Following Requirement is Applicable to Candidate Equivalent Methods Only

----------------------------------------------------------------------------------------------------------------
Sec. 53.59 Aerosol transport Aerosol transport 97%, min, for all Determine aerosol
test channels transport through
any new or
modified
components with
respect to the
reference method
sampler before
the filter for
each channel.
----------------------------------------------------------------------------------------------------------------

Table E-2.--Spectral Energy Distribution and Permitted Tolerance for Conducting Radiative Tests
----------------------------------------------------------------------------------------------------------------
Spectral Region
Chacteristic --------------------------------------------------------------------------
Ultraviolet Visible Infrared
----------------------------------------------------------------------------------------------------------------
Bandwidth (<greek-m>m) 0.28 to 0.32 10.32 0.40 to 0.78 0.78 to 3.00
to 0.40
Irradiance (W/m2) 5 56 450 to 550 439
Allowed Tolerance 2<plus-minus> 35% 2<plus-minus> 10% 2<plus-minus> 10%
2<plus-minus>
25%
----------------------------------------------------------------------------------------------------------------

[[Page 38813]]

Figures to Subpart E of Part 53

Figure E-1.--Designation Testing Checklist

DESIGNATION TESTING CHECKLIST

____________________ ____________________
____________________
Auditee Auditor signature Date

----------------------------------------------------------------------------------------------------------------
Compliance Status: Y = Yes N = No NA = Not applicable/Not available
---------------------------------------------------------------------------------------------
Verification Verified by Direct
------------------------------------------------------------------------- Observation of
Process or of Verification
Documented Comments (Includes
Evidence: documentation of
Performance, who, what, where,
Design or when, why) (Doc.
Y N NA Application Spec. #, Rev. #, Rev.
Corresponding to Date)
Sections of 40 CFR
Part 53 or 40 CFR
Part 50, Appendix
L
----------------------------------------------------------------------------------------------------------------
Performance
Specification
Tests
Sample flow rate
coefficient of
variation (Sec.
53.53) (L 7.4.3)
----------------------------------------------------------------------------------------------------------------
Filter temperature
control
(sampling) (Sec.
53.57) (L 7.4.10)
----------------------------------------------------------------------------------------------------------------
Elapsed sample
time accuracy
(Sec. 53.54) (L
7.4.13)
----------------------------------------------------------------------------------------------------------------
Filter temperature
control (post
sampling) (Sec.
53.57) (L 7.4.10)
----------------------------------------------------------------------------------------------------------------
Application
Specification
Tests
----------------------------------------------------------------------------------------------------------------
Field Precision
(Sec. 53.58) (L
5.1)
----------------------------------------------------------------------------------------------------------------
Meets all Appendix
L requirements
(part 53, subpart
A, Sec.
53.2(a)(3)) (part
53, subpart E,
Sec. 53.51(a),(d
))
----------------------------------------------------------------------------------------------------------------
Filter Weighing (L-
8)
----------------------------------------------------------------------------------------------------------------
Field Sampling
Procedure (Sec.
53.30, .31, .34)
----------------------------------------------------------------------------------------------------------------
Design
Specification
Tests
----------------------------------------------------------------------------------------------------------------
Filter ( L-6)
----------------------------------------------------------------------------------------------------------------
Range of
Operational
Conditions (L-
7.4.7)
----------------------------------------------------------------------------------------------------------------

The Following Requirements Apply Only to Class I Candidate Equivalent Methods

----------------------------------------------------------------------------------------------------------------
Aerosol Transport
(Sec. 53.59)
----------------------------------------------------------------------------------------------------------------

[[Page 38814]]

Figure E-2.--Product Manufacturing Checklist

PRODUCT MANUFACTURING CHECKLIST

____________________ ____________________
____________________
Auditee Auditor signature Date

----------------------------------------------------------------------------------------------------------------
Compliance Status: Y = Yes N = No NA = Not applicable/Not available
---------------------------------------------------------------------------------------------
Verification Verified by Direct
------------------------------------------------------------------------- Observation of
Process or of Verification
Documented Comments (Includes
Evidence: documentation of
Performance, who, what, where,
Design or when, why) (Doc.
Y N NA Application Spec. #, Rev. #, Rev.
Corresponding to Date)
Sections of 40 CFR
Part 53 or 40 CFR
Part 50, Appendix
L
----------------------------------------------------------------------------------------------------------------
Performance
Specification
Tests
----------------------------------------------------------------------------------------------------------------
Assembled
operational
performance (Burn-
in test) (Sec.
53.53)
----------------------------------------------------------------------------------------------------------------
Sample flow rate
(Sec. 53.53) (L
7.4.1, L 7.4.2)
----------------------------------------------------------------------------------------------------------------
Sample flow rate
regulation (Sec.
53.53) (L 7.4.3)
----------------------------------------------------------------------------------------------------------------
Flow rate and
average flow rate
measurement
accuracy (Sec.
53.53) (L 7.4.5)
----------------------------------------------------------------------------------------------------------------
Ambient air
temperature
measurement
accuracy (Sec.
53.55) (L 7.4.8)
----------------------------------------------------------------------------------------------------------------
Ambient
barometric
pressure
measurement
accuracy (Sec.
53.56) (L 7.4.9)
----------------------------------------------------------------------------------------------------------------
Sample flow rate
cut-off (Sec.
53.53) (L 7.4.4)
----------------------------------------------------------------------------------------------------------------
Sampler leak
check facility
(Sec. 53.52) (L
7.4.6)
----------------------------------------------------------------------------------------------------------------
Application
Specification
Tests
----------------------------------------------------------------------------------------------------------------
Flow rate
calibration
transfer standard
(L-9.2)
----------------------------------------------------------------------------------------------------------------
Operational /
Instructional
manual (L-7.4.18)
----------------------------------------------------------------------------------------------------------------
Design
Specification
Tests
----------------------------------------------------------------------------------------------------------------
Impactor (jet
width) (Sec.
53.51(d)(1)) (L-
7.3.4.1)
----------------------------------------------------------------------------------------------------------------
Surface finish
(Sec. 53.51(
d)(2)) (L-7.3.7)
----------------------------------------------------------------------------------------------------------------

Appendix A to Subpart E of Part 53--References
(1) Quality systems--Model for quality assurance in design,
development, production, installation and servicing, ISO 9001. July
1994. Available from American Society for Quality Control, 611 East
Wisconsin Avenue, Milwaukee, WI 53202.
(2) American National Standard--Specifications and Guidelines
for Quality Systems for Environmental Data Collection and
Environmental Technology Programs. ANSI/ASQC E4-1994. January 1995.
Available from American Society for Quality Control, 611 East
Wisconsin Avenue, Milwaukee, WI 53202.
(3) Copies of section 2.12 of the Quality Assurance Handbook for
Air Pollution Measurement Systems, Volume II, Ambient Air Specific
Methods, EPA/600/R-94/038b, are available from Department E (MD-
77B), U.S. EPA, Research Triangle Park, NC 27711.
(4) 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.
(5) Quality Assurance Handbook for Air Pollution Measurement
Systems, Volume IV: Meteorological Measurements. Revised March,
1995. 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).
(6) Military standard specification (mil. spec.) 810-E 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.
e. Subpart F is added to read as follows:
Subpart F--Procedures for Testing Performance Characteristics of Class
II Equivalent Methods for PM_2.5
Sec.

53.60 General provisions.
53.61 Test conditions for PM_2.5 reference method
equivalency.
53.62 Test procedure: Full wind tunnel test.
53.63 Test procedure: Wind tunnel inlet aspiration test.
53.64 Test procedure: Static fractionator test.
53.65 Test procedure: Loading test.
53.66 Test procedure: Volatility test.
Tables to Subpart F of Part 53
Table F-1--Performance Specifications for PM_2.5 Class II
Equivalent Samplers
Table F-2--Particle Sizes and Wind Speeds for Full Wind Tunnel Test,
Wind Tunnel

[[Page 38815]]

Inlet Aspiration Test, and Static Chamber Test
Table F-3--Critical Parameters of Idealized Ambient Particle Size
Distributions
Table F-4--Estimated Mass Concentration Measurement of
PM_2.5 for Idealized Coarse Aerosol Size Distribution
Table F-5--Estimated Mass Concentration Measurement of
PM_2.5 for Idealized ``Typical'' Coarse Aerosol Size
Distribution
Table F-6 Estimated Mass Concentration Measurement of
PM_2.5 for Idealized Fine Aerosol Size Distribution
Figures to Subpart F of Part 53
Figure F-1--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_2.5

Sec. 53.60 General provisions.

(a) This subpart sets forth the specific requirements that a
PM_2.5 sampler associated with a candidate Class II
equivalent method must meet to be designated as an equivalent method
for PM_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 and 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 paragraph (d) of
this section.
(d) Except as provided in paragraphs (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 40 CFR part 50, Appendix
L, and in subpart E of this part, except for specific deviations of the
inlet, fractionator, or filter.
(1) Inlet deviation. A sampler which has been determined to be a
Class II sampler solely because the design or construction of its inlet
deviates from the design or construction of the inlet 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. 53.63 (wind tunnel
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 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 its effective filtration area
deviates from that of the reference method filter 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) 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 effectiveness (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 candidate
sampler is challenged at wind speeds of 2 and 24 km/hr with
monodisperse aerosols of the size specified in Table F-2 of this
subpart. The experimental test results are then integrated with three
idealized ambient distributions (typical, fine, and coarse) to yield
the expected mass concentration measurement for each. The acceptance
criteria are based on the results of this numerical analysis and the
particle diameter for which the sampler effectiveness is 50 percent.
(2) Wind tunnel inlet aspiration test. The wind tunnel inlet
aspiration test directly compares the inlet of the candidate sampler to
the inlet of a reference method sampler with the single-sized, liquid,
monodisperse challenge aerosol specified in Table F-2 of this subpart
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 inlet and the reference method inlet.
(3) Static fractionator test. The static fractionator test
determines the effectiveness of the candidate sampler's 2.5-micron
fractionator under static conditions for aerosols of the size specified
in Table F-2 of this subpart. The numerical analysis procedures and
acceptance criteria are identical to those in the full wind tunnel test.
(4) Loading test. The loading test is conducted to ensure that the
performance of a candidate sampler is not significantly affected by the
amount of particulate deposited on its interior surfaces between
periodic cleanings. The candidate sampler is artificially loaded by
sampling a test environment containing aerosolized, standard test dust.
The duration of the loading phase is dependent on both the time between
cleaning as specified by the candidate method and the aerosol mass
concentration in the test environment. After loading, the candidate's
performance must then be evaluated by Sec. 53.62 (full wind tunnel
evaluation), Sec. 53.64 (wind tunnel inlet aspiration test), or
Sec. 53.64 (static fractionator test). If the results of the
appropriate test 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 cleaning
frequency proposed by the candidate method and that has been
demonstrated to be acceptable by this test.
(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 during a blow-off time period. Residual
mass is then calculated as the weight of the filter after the blow-off
phase is subtracted from the initial weight of the filter. Acceptance
criteria are based on a comparison of the residual mass measured by the
candidate sampler (corrected for flow rate variations from that of the
reference method) to the

[[Page 38816]]

residual mass measured by the reference method sampler for several
specified clean air sampling time periods.
(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 submit as part of the application, a
Designation Testing Checklist (Figure F-1 of this subpart) which has
been completed and signed by an ISO-certified auditor.

Sec. 53.61 Test conditions for PM_2.5 reference method
equivalency.

(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
section 7.4.18 of 40 CFR part 50, Appendix L.
(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 section 7.4.18 of 40 CFR part 50, Appendix L,
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 section 7.4.18 of 40
CFR part 50, Appendix L. 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 set up, calibrated, and maintained by qualified
personnel according to the manufacturer's instructions. All appropriate
calibration information and manuals for this equipment shall be kept on
file.
(g) Vibrating orifice aerosol generator conventions. This section
prescribes conventions regarding the use of the vibrating orifice
aerosol generator (VOAG) for the size-selective performance tests
outlined in Secs. 53.62, 53.63, 53.64, and 53.65.
(1) Particle aerodynamic diameter. The VOAG produces near-
monodisperse 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 near-
monodisperse size.
(i) The physical diameter of a generated spherical particle can be
calculated from the operating parameters of the VOAG as:

Equation 1
[GRAPHIC] [TIFF OMITTED] TR18JY97.094

where:
D<INF>p</INF> = particle physical diameter, <greek-m>m;
Q = liquid volumetric flow rate, <greek-m>m3/sec;
C<INF>vol</INF> = volume concentration (particle volume produced per
drop volume), dimensionless; and
f = frequency of applied vibrational signal, 1/sec.

(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</INF> = 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:

Equation 2
[GRAPHIC] [TIFF OMITTED] TR18JY97.095

where:
D<INF>ae</INF> = particle aerodynamic diameter, <greek-m>m;
<greek-r><INF>p</INF> = particle density, g/cm3;
<greek-r><INF>o</INF> = aerodynamic particle density = 1 g/
m3;
C<INF>Dp</INF> = Cunningham's slip correction factor for physical
particle diameter, dimensionless; and
C<INF>Dae</INF> = 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:

Equation 3
[GRAPHIC] [TIFF OMITTED] TR18JY97.096

Equation 4
[GRAPHIC] [TIFF OMITTED] TR18JY97.097

(iv) Since the slip correction factor is itself a function of
particle diameter, the aerodynamic diameter in Equation 2 of paragraph
(g)(1)(ii) of this section cannot be solved directly but must be
determined by iteration.
(2) Solid particle generation. (i) Solid particle tests performed
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>2</INF>0H<INF>12</INF>O<INF>5</INF>, FW = 332.31, CAS 2321-07-5)
with aqueous ammonia. Guidelines for preparation of fluorescein
solutions of the desired volume concentration (C<INF>vol</INF>) 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.
(ii) Mass deposits of ammonium fluorescein shall be extracted and
analyzed using solutions of 0.01 N ammonium hydroxide.
(3) Liquid particle generation. (i) 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>18</INF>H<INF>34</INF>O<INF>2</INF>, 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

[[Page 38817]]

dispensed mass by the oleic acid density.
(ii) 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>20</INF>H<INF>10</INF>O<INF>5</INF>Na<INF>2</INF>, 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.
(iii) Calculation of the physical diameter of the particles
produced by the VOAG requires knowledge of the liquid solution's volume
concentration (C<INF>vol</INF>). 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:

Equation 5
[GRAPHIC] [TIFF OMITTED] TR18JY97.098

where:
V<INF>u</INF> = uranine volume, ml;
V<INF>oleic</INF> = oleic acid volume, ml;
V<INF>sol</INF> = total solution volume, ml;
M<INF>u</INF> = uranine mass, g;
<greek-r><INF>u</INF> = uranine density, g/cm3;
M<INF>oleic</INF> = oleic acid mass, g; and
<greek-r><INF>oleic</INF> = oleic acid density, g/cm3.

(iv) For purposes of converting the particles' physical diameter to
aerodynamic diameter, the density of the generated particles shall be
calculated as:

Equation 6
[GRAPHIC] [TIFF OMITTED] TR18JY97.099

(v) Mass deposits of oleic acid shall be extracted and analyzed
using solutions of 0.01 N sodium hydroxide.

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 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
(D<INF>p50</INF>) at each wind speed is then determined from the
corrected effectiveness curves. The two resultant penetration curves
are then each numerically integrated with three idealized ambient
particle size distributions to provide six estimates 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 in the test
section.
(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 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 of the particle
population. 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 sizer,
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 2 percent and an accuracy 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 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. After cross-sectional
uniformity has been confirmed, 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 paragraph (d)(5) of this section.
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 fluorometer 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.
(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
NIST-traceable 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.

[[Page 38818]]

(ii) Measure the wind speed at a minimum of 12 test points in a
cross-sectional area of the test section of the wind tunnel using a
device as described in paragraph (c)(4) of this section.
(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. (i) Generate particles of a size specified in
Table F-2 of this subpart using a vibrating orifice aerosol generator.
(ii) Check for the presence of satellites and adjust the generator
as necessary.
(iii) Calculate the physical particle size using the operating
parameters of the vibrating orifice aerosol generator and record.
(iv) 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 technique does not
provide a direct measure of aerodynamic diameter, the geometric mean
aerodynamic diameter of the challenge aerosol must be calculated using
the known density of the particle and the measured mean physical
diameter. The determined geometric 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 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 (paragraph (c)(5) of this section). 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:

Equation 7
[GRAPHIC] [TIFF OMITTED] TR18JY97.100

where:
i = replicate number;
j = isokinetic sampler number;
M<INF>iso</INF> = mass of material collected with the isokinetic
sampler;
Q = isokinetic sampler volumetric flow rate; and
t = sampling time.

(iii) Calculate and record the mean mass concentration as:

Equation 8
[GRAPHIC] [TIFF OMITTED] TR18JY97.101

where:
i = replicate number;
j = isokinetic sampler number; and
n = total number of isokinetic samplers.

(iv) Precision calculation. (A) Calculate the coefficient of
variation of the mass concentration measurements as:

Equation 9
[GRAPHIC] [TIFF OMITTED] TR18JY97.102

where:
i = replicate number;
j = isokinetic sampler number; and
n = total number of isokinetic samplers.

(B) If the value of CV<INF>iso(i)</INF> 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 1 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 (paragraph
(c)(6) of this section).
(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)</INF> as in paragraph (d)(5)(ii) of this section.
(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 paragraph (c)(1) of this section 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:

Equation 10
[GRAPHIC] [TIFF OMITTED] TR18JY97.103

where:
i = replicate number;
M<INF>cand</INF> = mass of material collected with the candidate
sampler;
Q = candidate sampler volumetric flow rate; and
t = sampling time.

[[Page 38819]]

(iv)(A) Calculate and record the sampling effectiveness of the
candidate sampler as:

Equation 11
[GRAPHIC] [TIFF OMITTED] TR18JY97.104

where:
i = replicate number.

(B) If a single isokinetic sampler is used for the determination of
particle mass concentration, replace C<INF>iso(i)</INF> with
C<INF>iso</INF>.
(8) Replicate measurements and calculation of mean sampling
effectiveness. (i) Repeat steps in paragraphs (d)(5) through (d)(7) of
this section, as appropriate, to obtain a 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 as:

Equation 12
[GRAPHIC] [TIFF OMITTED] TR18JY97.105

where:
i = replicate number; and
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:

Equation 13
[GRAPHIC] [TIFF OMITTED] TR18JY97.106

where:
i = replicate number, and
n = number of replicates.

(B) If the value of CV<INF>E</INF> exceeds 10 percent, the test run
(steps in paragraphs (d)(2) through (d)(8) of this section) must be
repeated until an acceptable value is obtained.
(9) Repeat steps in paragraphs (d)(2) through (d)(8) of this
section until the sampling effectiveness has been measured for all
particle sizes specified in Table F-2 of this subpart.
(10) Repeat steps in paragraphs (d)(1) through (d)(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 average sampling effectiveness of the candidate sampler as a
function of aerodynamic particle diameter (D<INF>ae</INF>) 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). This multiplet-corrected
effectiveness curve shall be used for all remaining calculations in
this paragraph (e).
(2) Cutpoint determination. For each wind speed determine the
sampler Dp<INF>50</INF> 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 best-
fit, multiplet-corrected 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:

Equation 14
[GRAPHIC] [TIFF OMITTED] TR18JY97.107

where:
C<INF>cand(est)</INF> = estimated mass concentration measurement for
the test sampler, <greek-m>g/m3; and
C<INF>ref(est)</INF> = 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 (e)(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 R<INF>c</INF> 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 ensure that the
aspiration of a Class II candidate sampler is such that it
representatively extracts an ambient aerosol at elevated wind speeds.
This wind tunnel test uses a single-sized, 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) Setup. The candidate and reference method samplers shall be
operated with the PM_2.5 fractionation device removed from
the flow path throughout this entire test procedure. Modifications to
accommodate this requirement shall be limited to removal of the
fractionator and insertion of the filter holder directly into the
downtube of the inlet.
(e) Test procedure--(1) Establish the wind tunnel test atmosphere.
Follow the procedures in Sec. 53.62(d)(1) through (d)(4) to establish a
test atmosphere for one of the two wind speeds specified in Table F-2
of this subpart.

[[Page 38820]]

(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 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
reference method sampler using a calibrated fluorometer. Calculate and
record the mass concentration as:

Equation 15
[GRAPHIC] [TIFF OMITTED] TR18JY97.108

where:
i = replicate number;
M<INF>ref</INF> = mass of material collected with the reference
method sampler;
Q = reference method sampler volumetric flow rate; and
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:

Equation 16
[GRAPHIC] [TIFF OMITTED] TR18JY97.109

where:
i = replicate number;
M<INF>cand</INF> = mass of material collected with the candidate
sampler;
Q = candidate sampler volumetric flow rate; and
t = sampling time.

(iii) Remove the candidate sampler from the wind tunnel.
(4) Repeat steps in paragraphs (d) (2) and (d)(3) of this section.
Alternately measure the tunnel concentration with the reference sampler
and the candidate sampler until four reference sampler and three
candidate sampler measurements of the wind tunnel concentration are
obtained.
(5) Calculations. (i) Calculate and record aspiration ratio for
each candidate sampler run as:

Equation 17
[GRAPHIC] [TIFF OMITTED] TR18JY97.110

where:
i = replicate number.

(ii) Calculate and record the mean aspiration ratio as:

Equation 18
[GRAPHIC] [TIFF OMITTED] TR18JY97.111

where:
i = replicate number; and
n = total number of measurements of aspiration ratio.

(iii) Precision of the aspiration ratio. (A) Calculate and record
the precision of the aspiration ratio measurements as the coefficient
of variation as:

Equation 19
[GRAPHIC] [TIFF OMITTED] TR18JY97.112

where:
i = replicate number; and
n = total number of measurements of aspiration ratio.

(B) If the value of CV<INF>A</INF> exceeds 10 percent, the entire
test procedure must be repeated.
(f) Evaluation of test results. The candidate method passes the
inlet aspiration test if all values of 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 on the candidate sampler's after filter 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 sampler's after
filter versus that which exists in a static chamber. A calibrated
fluorometer shall 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 existing in the test
atmosphere.
(c) Facilities and equipment required--(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 shall be defined as follows:
(i) Wash-off test apparatus. The aerosol may be delivered to the
candidate fractionator through direct piping (with or without an in-
line mixing chamber). Validation particle size and quality shall be
conducted at a point directly upstream of the fractionator.

[[Page 38821]]

(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 in
addition to the inlet of the candidate method size fractionator.
Validation of particle size and quality 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 aerosol shall be delivered to a manifold with two
symmetrical branching legs. One of the legs, referred to as the bypass
leg, shall allow the challenge aerosol to pass unfractionated to the
detector. The other leg shall accommodate the fractionation device.
(3) Particle concentration measurement--(i) Fluorometry. Refer to
Sec. 53.62(c)(7).
(ii) Number concentration measurement. A number counting particle
sizer may be used in conjunction with the divided flow test apparatus
in lieu of fluorometric measurement. This device must have a minimum
range of 1 to 10 <greek-m>m, a resolution of 0.1 <greek-m>m, and an
accuracy of 0.15 <greek-m>m 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 and downtube from the candidate
fractionator. All tests procedures shall be conducted with the inlet
and downtube 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 wash-
off 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 Society of
Automotive Engineers Aerospace Material Specification (SAE AMS) 2404C,
Electroless Nickel Plating (Reference 3 in Appendix A of Subpart F).
(e) Test procedure: Wash-off method--(1) Clean the candidate
sampler. Note: The procedures in this step may be omitted if this test
is being used to evaluate the fractionator after being loaded as
specified in Sec. 53.65.
(i) Clean and dry the internal surfaces of the candidate sampler.
(ii) Prepare the internal fractionator surfaces in strict
accordance with the operating instructions specified in the sampler's
operating manual referred to in section 7.4.18 of 40 CFR part 50,
Appendix L.
(2) Generate aerosol. Follow the procedures for aerosol generation
prescribed in Sec. 53.62(d)(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(d)(4).
(4) Determine effectiveness for the particle size being produced.
(i) Collect particles downstream of the fractionator on an appropriate
filter over a time period such that the relative error of the
fluorometric measurement is less than 5.0 percent.
(ii) Determine the quantity of material collected on the after
filter of the candidate method using a calibrated fluorometer.
Calculate and record the aerosol mass concentration for the sampler
filter as:

Equation 20
[GRAPHIC] [TIFF OMITTED] TR18JY97.113

where:
i = replicate number;
M<INF>cand</INF> = mass of material collected with the candidate
sampler;
Q = candidate sampler volumetric flowrate; and
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:

Equation 21
[GRAPHIC] [TIFF OMITTED] TR18JY97.114

where:
i = replicate number;
M<INF>wash</INF> = mass of material washed from the interior
surfaces of the fractionator;
Q = candidate sampler volumetric flowrate; and
t = sampling time.

(iv) Calculate and record the sampling effectiveness of the test
sampler for this particle size as:

Equation 22
[GRAPHIC] [TIFF OMITTED] TR18JY97.115

where:
i = replicate number.

(v) Repeat steps in paragraphs (e)(4) of this section, as
appropriate, to obtain a minimum of three replicate measurements of
sampling effectiveness. Note: The procedures for loading the candidate
in Sec. 53.65 must be repeated between repetitions if this test is
being used to evaluate the fractionator after being loaded as specified
in Sec. 53.65.
(vi) Calculate and record the average sampling effectiveness of the
test sampler as:

Equation 23
[GRAPHIC] [TIFF OMITTED] TR18JY97.116

where:
i = replicate number; and
n = number of replicates.

(vii)(A) Calculate and record the coefficient of variation for the
replicate sampling effectiveness measurements of the test sampler as:

Equation 24
[GRAPHIC] [TIFF OMITTED] TR18JY97.117

where:
i = replicate number; and
n = total number of measurements.
(B) If the value of CV<INF>E</INF> exceeds 10 percent, then steps
in paragraphs (e) (2) through (e)(4) of this section must be repeated.
(5) Repeat steps in paragraphs (e) (1) through (e)(4) of this
section for each particle size 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(d)(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(d)(4).
(3) Introduce particles into chamber. Introduce the particles into
the static chamber and allow the particle concentration to stabilize.
(4) Install and operate the candidate sampler's fractionator and
its after-filter and at least four total filters. (i) Install the
fractionator and an array of four or more equally spaced total filter
samplers such that the total filters surround and are in the same plane
as the inlet of the fractionator.
(ii) Simultaneously collect particles onto appropriate filters with
the total filter samplers and the fractionator for a time period such
that the relative error

[[Page 38822]]

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:

Equation 25
[GRAPHIC] [TIFF OMITTED] TR18JY97.118

where:
i = replicate number;
j = total filter sampler number;
M<INF>total</INF> = mass of material collected with the total filter
sampler;
Q = total filter sampler volumetric flowrate; and
t = sample time.

(ii) Calculate and record the mean mass concentration as:

Equation 26
[GRAPHIC] [TIFF OMITTED] TR18JY97.119

where:
n = total number of samplers;
i = replicate number; and
j = filter sampler number.

(iii) (A) Calculate and record the coefficient of variation of the
total mass concentration as:

Equation 27
[GRAPHIC] [TIFF OMITTED] TR18JY97.120

where:
i = replicate number;
j = total filter sampler number; and
n = number of total filter samplers.

(B) If the value of CV<INF>total</INF> 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 (f)(5) of this section must be repeated.
(6) Determine the effectiveness of the candidate sampler. (i)
Determine the quantity of material collected on the candidate sampler's
after filter using a calibrated fluorometer. Calculate and record the
mass concentration for the candidate sampler as:

Equation 28
[GRAPHIC] [TIFF OMITTED] TR18JY97.121

where:
i = replicate number;
M<INF>cand</INF> = mass of material collected with the candidate
sampler;
Q = candidate sampler volumetric flowrate; and
t = sample time.

(ii) Calculate and record the sampling effectiveness of the
candidate sampler as:

Equation 29
[GRAPHIC] [TIFF OMITTED] TR18JY97.122

where:
i = replicate number.

(iii) Repeat step in paragraph (f)(4) through (f)(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:

Equation 30
[GRAPHIC] [TIFF OMITTED] TR18JY97.123

where:
i= replicate number.

(v)(A) Calculate and record the coefficient of variation for the
replicate sampling effectiveness measurements of the test sampler as:

Equation 31
[GRAPHIC] [TIFF OMITTED] TR18JY97.124

where:
i = replicate number; and
n = number of measurements of effectiveness.

(B) If the value of CV<INF>E</INF> exceeds 10 percent, then the
test run (steps in paragraphs (f)(2) through (f)(6) of this section) is
unacceptable and must be repeated.
(7) Repeat steps in paragraphs (f)(1) through (f)(6) of this
section for each particle size 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(d)(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(d)(4).
(3) Introduce aerosol. 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 as a detector:
(A) Install a total filter on each leg of the divided flow apparatus.
(B) Collect particles simultaneously through both legs at 16.7 L/
min 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:

Equation 32
[GRAPHIC] [TIFF OMITTED] TR18JY97.125

where:
i = replicate number,
M = mass of material collected with the total filter; and
Q = candidate sampler volumetric flowrate.

(D) Repeat steps in paragraphs (g)(4)(i)(A) through (g)(4)(i)(C) of
this section 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.

[[Page 38823]]

(B) Quantify the aerosol concentration of the primary particles in
each leg of the apparatus.
(C) Repeat steps in paragraphs (g)(4)(ii)(A) through (g)(4)(ii)(B)
of this section until a minimum of three replicate measurements are
performed.
(iii) (A) Calculate the mean concentration and coefficient of
variation as:

Equation 33
[GRAPHIC] [TIFF OMITTED] TR18JY97.126

Equation 34
[GRAPHIC] [TIFF OMITTED] TR18JY97.127

where:
i = replicate number; and
n = number of replicates.

(B) If the measured mean concentrations through the two legs do not
agree within 5 percent, then adjustments may be made in the setup, and
this step must be repeated.
(5) Determine effectiveness. 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) Prepare the divided flow apparatus for particle collection.
Install a total filter into the bypass leg of the divided flow
apparatus. Install the particle size fractionator with a total filter
placed immediately downstream of it into the other leg.
(B) Collect particles simultaneously through both legs at 16.7 L/
min 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:

Equation 35
[GRAPHIC] [TIFF OMITTED] TR18JY97.128

Equation 36
[GRAPHIC] [TIFF OMITTED] TR18JY97.129

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)</INF>.
(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)</INF>.
(iii) Calculate and record sampling effectiveness of the candidate
sampler as:

Equation 37
[GRAPHIC] [TIFF OMITTED] TR18JY97.130

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 coefficient of variation for replicate
measurements of effectiveness. (i) Calculate and record the mean
sampling effectiveness of the candidate sampler as:

Equation 38
[GRAPHIC] [TIFF OMITTED] TR18JY97.131

where:
i = replicate number.

(ii)(A) Calculate and record the coefficient of variation for the
replicate sampling effectiveness measurements of the candidate sampler as:

Equation 39
[GRAPHIC] [TIFF OMITTED] TR18JY97.132

where:
i = replicate number; and
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
(g)(7) of this section).
(8) Repeat steps in paragraphs (g)(1) through (g)(7) of this
section for each particle size 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 (as described in paragraph (c)(3)(ii)) of this section
will not require multiplet correction.
(2) Cutpoint determination. For each wind speed determine the
sampler Dp<INF>50</INF> 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(e)(3) through
(e)(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 Rc and Dp<INF>50</INF> 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 sampler's performance as a
function of coarse aerosol collection. The candidate sampler is exposed
to a mass of coarse aerosol equivalent to sampling a mass concentration
of 150 <greek-m>g/m3 over the time period that the
manufacturer has specified between periodic cleaning. After loading,
the candidate sampler is then evaluated by performing the test in
Sec. 53.62 (full wind tunnel test), Sec. 53.63 (wind tunnel inlet
aspiration test), or Sec. 53.64 (static fractionator test). If the
acceptance criteria are met for this evaluation test, then the
candidate sampler is approved for multi-day sampling with the periodic
maintenance schedule as specified by the candidate method. For example,
if the candidate sampler passes the reevaluation tests following
loading with an aerosol mass equivalent to sampling a 150 <greek-m>g/
m3 aerosol continuously for 7 days, then the sampler is
approved for 7 day field operation before cleaning is required.
(b) Technical definition. 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.
(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

[[Page 38824]]

sufficiently large cross-sectional 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). A fluidized bed aerosol generator, Wright dust
feeder, or sonic nozzle shall be used to efficiently deagglomerate the
bulk test dust and transform it into an aerosol cloud. 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.
(4) Analytic balance. An analytical balance shall be used to
determine the weight of the total filter in the isokinetic sampler. The
precision and accuracy of this device shall be such that the relative
measurement error is less than 5.0 percent for the difference between
the initial and final weight of the total filter. The identical
analytic balance shall be used to perform both initial and final
weighing of the total filter.
(d) Test procedure. (1) Calculate and record the target time
weighted concentration of Arizona road dust which is equivalent to
exposing the sampler to an environment of 150 <greek-m>g/m3
over the time between cleaning specified by the candidate sampler's
operations manual as:

Equation 40
[GRAPHIC] [TIFF OMITTED] TR18JY97.133

where:
t = the number of hours specified by the candidate method prior to
periodic cleaning.

(2) Clean the candidate sampler. (i) Clean and dry the internal
surfaces of the candidate sampler.
(ii) Prepare the internal surfaces in strict accordance with the
operating manual referred to in section 7.4.18 of 40 CFR part 50,
Appendix L.
(3) Determine the preweight of the filter that shall be used in the
isokinetic sampler. Record this value as InitWt.
(4) Install the candidate sampler's inlet and the isokinetic
sampler within the test chamber or wind tunnel.
(5) Generate a dust cloud. (i) Generate a dust cloud composed of
Arizona test dust.
(ii) Introduce the dust cloud into the chamber.
(iii) Allow sufficient time for the particle concentration to
become steady within the chamber.
(6) Sample aerosol with a total filter and the candidate sampler.
(i) Sample the aerosol for a time sufficient to produce an equivalent
TWC equal to that of the target TWC <plus-minus> 15 percent.
(ii) Record the sampling time as t.
(7) Determine the time weighted concentration. (i) Determine the
postweight of the isokinetic sampler's total filter.
(ii) Record this value as FinalWt.
(iii) Calculate and record the TWC as:

Equation 41
[GRAPHIC] [TIFF OMITTED] TR18JY97.134

where:
Q = the flow rate of the candidate method.

(iv) If the value of TWC deviates from the target TWC <plus-minus>
15 percent, then the loaded mass is unacceptable and the entire test
procedure must be repeated.
(8) Determine the candidate sampler's effectiveness after 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 inlet deviation in Sec. 53.60(e)(1) may opt to perform the test in
Sec. 53.63 (inlet aspiration test) in lieu of the 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 results. If the candidate sampler meets the acceptance
criteria for the evaluation test performed in paragraph (d)(8) of this
section, then the candidate sampler passes this test with the
stipulation that the sampling train be cleaned as directed by and as
frequently as that specified by the candidate sampler's operations manual.

Sec. 53.66 Test procedure: Volatility test.

(a) Overview. This test is designed to ensure that the candidate
method's losses due to volatility when sampling semi-volatile ambient
aerosol will be comparable to that of a federal reference method
sampler. This is accomplished by challenging the candidate sampler with
a polydisperse, semi-volatile liquid aerosol in three distinct phases.
During phase A of this test, the aerosol is elevated to a steady-state,
test-specified mass concentration and the sample filters are
conditioned and preweighed. In phase B, the challenge aerosol is
simultaneously sampled by the candidate method sampler and a reference
method sampler onto the preweighed filters for a specified time period.
In phase C (the blow-off phase), aerosol and aerosol-vapor free air is
sampled by the samplers for an additional time period to partially
volatilize the aerosol on the filters. The candidate sampler passes the
volatility test if the acceptance criteria presented in Table F-1 of
this subpart are met or exceeded.
(b) Technical definitions. (1) Residual mass (RM) is defined as the
weight of the filter after the blow-off phase subtracted from the
initial weight of the filter.
(2) Corrected residual mass (CRM) is defined as the residual mass
of the filter from the candidate sampler multiplied by the ratio of the
reference method flow rate to the candidate method flow rate.
(c) Facilities and equipment required--(1) Environmental chamber.
Because the nature of a volatile aerosol is greatly dependent upon
environmental conditions, all phases of this test shall be conducted at
a temperature of 22.0 <plus-minus> 0.5 deg.C and a relative humidity
of 40 <plus-minus> 3 percent. For this reason, it is strongly advised
that all weighing and experimental apparatus be housed in an
environmental chamber capable of this level of control.
(2) Aerosol generator. The aerosol generator shall be a pressure
nebulizer operated at 20 to 30 psig (140 to 207 kPa) to produce a
polydisperse, semi-voltile aerosol with a mass median diameter larger
than 1 <greek-m>m and smaller than 2.5 <greek-m>m. The nebulized liquid
shall be A.C.S. reagent grade glycerol
(C<INF>3</INF>H<INF>8</INF>O<INF></INF>, FW = 92.09, CAS 56-81-5) of
99.5 percent minimum purity. For the purpose of this test the accepted
mass median diameter is predicated on the stable aerosol inside the
internal chamber and not on the aerosol emerging from the nebulizer
nozzle. Aerosol monitoring and its stability are described in (c)(3)
and (c)(4) of this section.
(3) Aerosol monitoring equipment. The evaporation and condensation
dynamics of a volatile aerosol is greatly dependent upon the vapor
pressure of the volatile component in the carrier gas. The size of an
aerosol becomes fixed only when an equilibrium is established between
the aerosol and the surrounding vapor; therefore, aerosol

[[Page 38825]]

size measurement shall be used as a surrogate measure of this
equilibrium. A suitable instrument with a range of 0.3 to 10
<greek-m>m, an accuracy of 0.5 <greek-m>m, and a resolution of 0.2
<greek-m>m (e.g., an optical particle sizer, or a time-of-flight
instrument) shall be used for this purpose. The parameter monitored for
stability shall be the mass median instrument measured diameter (i.e.
optical diameter if an optical particle counter is used). A stable
aerosol shall be defined as an aerosol with a mass median diameter that
has changed less than 0.25 <greek-m>m over a 4 hour time period.
(4) Internal chamber. The time required to achieve a stable aerosol
depends upon the time during which the aerosol is resident with the
surrounding air. This is a function of the internal volume of the
aerosol transport system and may be facilitated by recirculating the
challenge aerosol. A chamber with a volume of 0.5 m3 and a
recirculating loop (airflow of approximately 500 cfm) is recommended
for this purpose. In addition, a baffle is recommended to dissipate the
jet of air that the recirculating loop can create. Furthermore, a HEPA
filtered hole in the wall of the chamber is suggested to allow makeup
air to enter the chamber or excess air to exit the chamber to maintain
a system flow balance. The concentration inside the chamber shall be
maintained at 1 mg/m3 <plus-minus> 20 percent to obtain
consistent and significant filter loading.
(5) Aerosol sampling manifold. A manifold shall be used to extract
the aerosol from the area in which it is equilibrated and transport it
to the candidate method sampler, the reference method sampler, and the
aerosol monitor. The losses in each leg of the manifold shall be
equivalent such that the three devices will be exposed to an identical
aerosol.
(6) Chamber air temperature recorders. Minimum range 15-25 deg.C,
certified accuracy to within 0.2 deg.C, resolution of 0.1 deg.C.
Measurement shall be made at the intake to the sampling manifold and
adjacent to the weighing location.
(7) Chamber air relative humidity recorders. Minimum range 30 - 50
percent, certified accuracy to within 1 percent, resolution of 0.5
percent. Measurement shall be made at the intake to the sampling
manifold and adjacent to the weighing location.
(8) Clean air generation system. A source of aerosol and aerosol-
vapor free air is required for phase C of this test. This clean air
shall be produced by filtering air through an absolute (HEPA) filter.
(9) Balance. Minimum range 0 - 200 mg, certified accuracy to within
10 <greek-m>g, resolution of 1 <greek-m>g.
(d) Additional filter handling conditions. (1) 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 dynamic conditioning and phase C.
(2) Dynamic conditioning of filters. Total dynamic conditioning is
required prior to the initial weight determined in phase A. Dynamic
conditioning refers to pulling clean air from the clean air generation
system through the filters. 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.
(3) 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.
(e) Test procedure--(1) Phase A - Preliminary steps. (i) Generate a
polydisperse glycerol test aerosol.
(ii) Introduce the aerosol into the transport system.
(iii) Monitor the aerosol size and concentration until stability
and level have been achieved.
(iv) Condition the candidate method sampler and reference method
sampler filters until total dynamic conditioning is achieved as
specified in paragraph (d)(2) of this section.
(v) Record the dynamically conditioned weight as InitWt<INF>c</INF>
and InitWt<INF>r</INF> where c is the candidate method sampler and r is
the reference method sampler.
(2) Phase B - Aerosol loading. (i) Install the dynamically
conditioned filters into the appropriate samplers.
(ii) Attach the samplers to the manifold.
(iii) Operate the candidate and the reference samplers such that
they simultaneously sample the test aerosol for 30 minutes.
(3) Phase C - Blow-off. (i) Alter the intake of the samplers to
sample air from the clean air generation system.
(ii) Sample clean air for one of the required blow-off time
durations (1, 2, 3, and 4 hours).
(iii) Remove the filters from the samplers.
(iv) Weigh the filters immediately and record this weight,
FinalWt<INF>c</INF> and FinalWt<INF>r</INF>, where c is the candidate
method sampler and r is the reference method sampler.
(v) Calculate the residual mass for the reference method sampler:

Equation 41a
[GRAPHIC] [TIFF OMITTED] TR18JY97.135

where:
i = repetition number; and
j = blow-off time period.

(vi) Calculate the corrected residual mass for the candidate method
sampler as:

Equation 41b
[GRAPHIC] [TIFF OMITTED] TR18JY97.136

where:
i = repetition number;
j = blow-off time period;
Q<INF>c</INF> = candidate method sampler flow rate, and
Q<INF>r</INF> = reference method sampler flow rate.

(4) Repeat steps in paragraph (e)(1) through (e)(3) of this section
until three repetitions have been completed for each of the required
blow-off time durations (1, 2, 3, and 4 hours).
(f) Calculations and analysis. (1) Perform a linear regression with
the candidate method CRM as the dependent variable and the reference
method RM as the independent variable.
(2) Determine the following regression parameters: slope,
intercept, and correlation coefficient (r).
(g) Test results. The candidate method passes the volatility test
if the regression parameters meet the acceptance criteria specified in
Table F-1 of this subpart.

Tables to Subpart F of Part 53

[[Page 38826]]

Table F-1.--Performance Specifications for PM<INF>2.5 Class II Equivalent
Samplers
------------------------------------------------------------------------
Acceptance
Performance Test Specifications Criteria
------------------------------------------------------------------------
Sec. 53.62 Full Wind Tunnel Solid VOAG produced Dp<INF>50 = 2.5 <greek-
Evaluation. aerosol at 2 km/hr m>m <plus-minus>
and 24 km/hr. 0.2 <greek-m>m;
Numerical
Analysis Results:
95% <ls-thn-
eq>R<INF>c<ls-thn-eq>1
05%
Sec. 53.63 Wind Tunnel Inlet Liquid VOAG Relative
Aspiration Test. produced aerosol Aspiration: 95%
at 2 km/hr and 24 <ls-thn-eq>A<ls-t
km/hr h105%
Sec. 53.64 Static Fractionator Evaluation of the Dp<INF>50 = 2.5 <greek-
Test. fractionator under m>m <plus-minus>
static conditions 0.2 <greek-m>m;
Numerical
Analysis Results:
95% <ls-thn-
eq>R<INF>c<ls-thn-eq>1
05%
Sec. 53.65 Loading Test....... Loading of the Acceptance
clean candidate criteria as
under laboratory specified in the
conditions post-loading
evaluation test
(Sec. 53.62,
Sec. 53.63, or
Sec. 53.64)
Sec. 53.66 Volatility Test.... Polydisperse liquid Regression
aerosol produced Parameters Slope
by air = 1 <plus-minus>
nebulization of 0.1, Intercept =
A.C.S. reagent 0 <plus-minus>
grade glycerol, 0.15 r 0.97
99.5% minimum
purity
------------------------------------------------------------------------

Table F-2.--Particle Sizes and Wind Speeds for Full Wind Tunnel Test, Wind Tunnel Inlet Aspiration Test, and
Static Chamber Test
----------------------------------------------------------------------------------------------------------------
Full Wind Tunnel Test Inlet Aspiration Test Static
Primary Partical Mean Size a (<greek- ------------------------------------------------ Fractionator Volatility
m>m) 2 km/hr 24 km/hr 2 km/hr 24 km/hr Test Test
----------------------------------------------------------------------------------------------------------------
1.5<plus-minus>0.25................... S S S
2.0<plus-minus>0.25................... S S S
2.2<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
3.0<plus-minus>0.25................... L L
3.5<plus-minus>0.25................... S S S
4.0<plus-minus>0.5.................... S S S
Polydisperse Glycerol Aerosol......... L
----------------------------------------------------------------------------------------------------------------
a Aerodynamic diameter.
S=Solid particles.
L=Liquid particles.

Table F-3.--Critical Parameters of Idealized Ambient Particle Size Distributions
--------------------------------------------------------------------------------------------------------------------------------------------------------
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
--------------------------------------------------------------------------------------------------------------------------------------------------------

Table F-4.--Estimated Mass Concentration Measurement of PM<INF>2.5 for Idealized Coarse Aerosol Size Distribution
--------------------------------------------------------------------------------------------------------------------------------------------------------
Test Sampler Ideal Sampler
-----------------------------------------------------------------------------------------------------------------------
Particle Aerodynamic Diameter Estimated Mass Estimated Mass
(<greek-m>m) Fractional Interval Mass Concentration Fractional Interval Mass Concentration
Sampling Concentration Measurement Sampling Concentration Measurement
Effectiveness (<greek-m>g/m3) (<greek-m>g/m3) Effectiveness (<greek-m>g/m3) (<greek-m>g/m3)
--------------------------------------------------------------------------------------------------------------------------------------------------------
(1) (2) (3) (4) (5) (6) (7)
--------------------------------------------------------------------------------------------------------------------------------------------------------
<0.500 1.000 6.001 1.000 6.001 6.001
0.625 2.129 0.999 2.129 2.127
0.750 0.982 0.998 0.982 0.980
0.875 0.730 0.997 0.730 0.728
1.000 0.551 0.995 0.551 0.548
1.125 0.428 0.991 0.428 0.424
1.250 0.346 0.987 0.346 0.342
1.375 0.294 0.980 0.294 0.288
1.500 0.264 0.969 0.264 0.256
1.675 0.251 0.954 0.251 0.239
1.750 0.250 0.932 0.250 0.233
1.875 0.258 0.899 0.258 0.232

[[Page 38827]]

2.000 0.272 0.854 0.272 0.232
2.125 0.292 0.791 0.292 0.231
2.250 0.314 0.707 0.314 0.222
2.375 0.339 0.602 0.339 0.204
2.500 0.366 0.480 0.366 0.176
2.625 0.394 0.351 0.394 0.138
2.750 0.422 0.230 0.422 0.097
2.875 0.449 0.133 0.449 0.060
3.000 0.477 0.067 0.477 0.032
3.125 0.504 0.030 0.504 0.015
3.250 0.530 0.012 0.530 0.006
3.375 0.555 0.004 0.555 0.002
3.500 0.579 0.001 0.579 0.001
3.625 0.602 0.000000 0.602 0.000000
3.750 0.624 0.000000 0.624 0.000000
3.875 0.644 0.000000 0.644 0.000000
4.000 0.663 0.000000 0.663 0.000000
4.125 0.681 0.000000 0.681 0.000000
4.250 0.697 0.000000 0.697 0.000000
4.375 0.712 0.000000 0.712 0.000000
4.500 0.726 0.000000 0.726 0.000000
4.625 0.738 0.000000 0.738 0.000000
4.750 0.750 0.000000 0.750 0.000000
4.875 0.760 0.000000 0.760 0.000000
5.000 0.769 0.000000 0.769 0.000000
5.125 0.777 0.000000 0.777 0.000000
5.250 0.783 0.000000 0.783 0.000000
5.375 0.789 0.000000 0.789 0.000000
5.500 0.794 0.000000 0.794 0.000000
5.625 0.798 0.000000 0.798 0.000000
5.75 0.801 0.000000 0.801 0.000000
C<INF>sam(exp)= C<INF>ideal(exp)= 13.814
--------------------------------------------------------------------------------------------------------------------------------------------------------

[[Page 38828]]

Table F-5.--Estimated Mass Concentration Measurement of PM<INF>2.5 for Idealized ``Typical'' Coarse Aerosol Size Distribution
--------------------------------------------------------------------------------------------------------------------------------------------------------
Test Sampler Ideal Sampler
-----------------------------------------------------------------------------------------------------------------------
Particle Aerodynamic Diameter Estimated Mass Estimated Mass
(<greek-m>m) Fractional Interval Mass Concentration Fractional Interval Mass Concentration
Sampling Concentration Measurement Sampling Concentration Measurement
Effectiveness (<greek-m>g/m3) (<greek-m>g/m3) Effectiveness (<greek-m>g/m3) (<greek-m>g/m3)
--------------------------------------------------------------------------------------------------------------------------------------------------------
(1) (2) (3) (4) (5) (6) (7)
--------------------------------------------------------------------------------------------------------------------------------------------------------
<0.500 1.000 16.651 1.000 16.651 16.651
0.625 5.899 0.999 5.899 5.893
0.750 2.708 0.998 2.708 2.703
0.875 1.996 0.997 1.996 1.990
1.000 1.478 0.995 1.478 1.471
1.125 1.108 0.991 1.108 1.098
1.250 0.846 0.987 0.846 0.835
1.375 0.661 0.980 0.661 0.648
1.500 0.532 0.969 0.532 0.516
1.675 0.444 0.954 0.444 0.424
1.750 0.384 0.932 0.384 0.358
1.875 0.347 0.899 0.347 0.312
2.000 0.325 0.854 0.325 0.277
2.125 0.314 0.791 0.314 0.248
2.250 0.312 0.707 0.312 0.221
2.375 0.316 0.602 0.316 0.190
2.500 0.325 0.480 0.325 0.156
2.625 0.336 0.351 0.336 0.118
2.750 0.350 0.230 0.350 0.081
2.875 0.366 0.133 0.366 0.049
3.000 0.382 0.067 0.382 0.026
3.125 0.399 0.030 0.399 0.012
3.250 0.416 0.012 0.416 0.005
3.375 0.432 0.004 0.432 0.002
3.500 0.449 0.001 0.449 0.000000
3.625 0.464 0.000000 0.464 0.000000
3.750 0.480 0.000000 0.480 0.000000
3.875 0.494 0.000000 0.494 0.000000
4.000 0.507 0.000000 0.507 0.000000
4.125 0.520 0.000000 0.520 0.000000
4.250 0.000000 0.532 0.000000
4.375 0.000000 0.543 0.000000
4.500 0.000000 0.553 0.000000
4.625 0.000000 0.562 0.000000
4.750 0.000000 0.570 0.000000
4.875 0.000000 0.577 0.000000
5.000 0.000000 0.584 0.000000
5.125 0.000000 0.590 0.000000
5.250 0.000000 0.595 0.000000
5.375 0.000000 0.599 0.000000
5.500 0.000000 0.603 0.000000
5.625 0.000000 0.605 0.000000
5.75 0.000000 0.608 0.000000
C<INF>sam(exp)= C<INF>ideal(exp)= 34.284
--------------------------------------------------------------------------------------------------------------------------------------------------------

[[Page 38829]]

Table F-6.--Estimated Mass Concentration Measurement of PM<INF>2.5 for Idealized Fine Aerosol Size Distribution
--------------------------------------------------------------------------------------------------------------------------------------------------------
Test Sampler Ideal Sampler
-----------------------------------------------------------------------------------------------------------------------
Particle Aerodynamic Diameter Estimated Mass Estimated Mass
(<greek-m>m) Fractional Interval Mass Concentration Fractional Interval Mass Concentration
Sampling Concentration Measurement Sampling Concentration Measurement
Effectiveness (<greek-m>g/m3) (<greek-m>g/m3) Effectiveness (<greek-m>g/m3) (<greek-m>g/m3)
--------------------------------------------------------------------------------------------------------------------------------------------------------
(1) (2) (3) (4) (5) (6) (7)
--------------------------------------------------------------------------------------------------------------------------------------------------------
<0.500 1.000 18.868 1.000 18.868 18.868
0.625 13.412 0.999 13.412 13.399
0.750 8.014 0.998 8.014 7.998
0.875 6.984 0.997 6.984 6.963
1.000 5.954 0.995 5.954 5.924
1.125 5.015 0.991 5.015 4.970
1.250 4.197 0.987 4.197 4.142
1.375 3.503 0.980 3.503 3.433
1.500 2.921 0.969 2.921 2.830
1.675 2.438 0.954 2.438 2.326
1.750 2.039 0.932 2.039 1.900
1.875 1.709 0.899 1.709 1.536
2.000 1.437 0.854 1.437 1.227
2.125 1.212 0.791 1.212 0.959
2.250 1.026 0.707 1.026 0.725
2.375 0.873 0.602 0.873 0.526
2.500 0.745 0.480 0.745 0.358
2.625 0.638 0.351 0.638 0.224
2.750 0.550 0.230 0.550 0.127
2.875 0.476 0.133 0.476 0.063
3.000 0.414 0.067 0.414 0.028
3.125 0.362 0.030 0.362 0.011
3.250 0.319 0.012 0.319 0.004
3.375 0.282 0.004 0.282 0.001
3.500 0.252 0.001 0.252 0.000000
3.625 0.226 0.000000 0.226 0.000000
3.750 0.204 0.000000 0.204 0.000000
3.875 0.185 0.000000 0.185

Revised Requirements for Designation of Reference and Equivalent Methods for PM2.5 and Ambient Air Quality Surveillance for Particulate Matter

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Revised Requirements for Designation of Reference and Equivalent Methods for PM_2.5 and Ambient Air Quality Surveillance for Particulate Matter