Document Released for Stakeholder Review and Comment

Evaluating Multiple Day Diurnal Evaporative Emissions Using RTD Tests

Report Number EPA420-99-003 

MOBILE6 Number M6.EVP.003

The office of Mobile Sources, Assessment and Modeling Division
announces the release of "Evaluating Multiple Day Diurnal Evaporative
Emissions Using RTD Tests" for stakeholder review and comment.  This
document EPA420-P-99-003 also known as document M6.EVP.003.is
available at the MOBILE6 section of the OMS Web Site
( http://www.epa.gov/oms/m6.htm)

This draft report presents an analysis of diurnal evaporative emissions from
light-duty vehicles (LDVs) and light-duty trucks (LDTs) occurring over
periods of more than one day, using real-time diurnal (RTD) test data from
testing programs performed under contract for EPA.

The data consists of hourly values of HC emissions (in grams)measured
under varying conditions of fuel Reid vapor pressure (RVP) and ambient
temperature.  Daily totals are obtained directly from these hourly values.

Comments on this report and its proposed use in MOBILE6 should be sent
to the attention of Phil Enns.  Comments may be submitted electronically to 
by fax to (734) 214-4939, or by mail to MOBILE6 Review Comments, US
EPA Assessment and Modeling Division, 2000 Traverwood Drive, Ann
Arbor, MI 48105.  Electronic submission of comments is preferred.  In
your comments please note clearly the document that you are commenting
on including the report title and the code number listed.  Please be sure to
include your name, address, affiliation and any other pertinent information.

This document is being released and posted on March 9, 1999.  Comments
will be accepted for sixty (60) days, until May 10, 1999. EPA will then
review and consider all comments received and will provide a summary of
those comments and how we are responding to them in the form of a
follow-up document.

Thank you for your continuing interest in the development of MOBILE6.

Sincerely,

Emission Inventory Group, Assessment and Modeling Division, US EPA,
Office of Mobile Sources