U.S. Environmental Protection Agency

May 17, 1999

    Document Released for Stakeholder Review and Comment
     
"Determining Repair Effects on IM240 Cold Start Emissions for
1981 and later Light Duty Vehicles"


Report Number EPA420-P-99-019
 
The office of Mobile Sources, Assessment and Modeling Division 
announces the release of "Determining Repair Effects on IM240 
Cold Start Emissions for 1981 and later Light Duty Vehicles"
for stakeholder review and comment.  This document EPA420-P99-019 
also known as document M6.IM.002.is available at the MOBILE6 
section of the OMS Web Site

When the MOBILE model calculates credits from Inspection and 
Maintenance (I/M) programs, one important input is the difference 
between emissions before and after successful I/M repairs. These 
"repair effects" may vary with vehicle type and model year. 
They also may vary with test type and test cutpoints, and may be 
different for running and start emissions. 

This document examines the repair effects on start emissions. It 
describes how the database for this analysis was developed. It 
also describes how to calculate cold start emissions from the 
Federal Test Procedure (FTP) bag results. The analysis in this 
report covers Light Duty Vehicles (LDVs) and Light Duty Trucks 
(LDTs) with model years ranging from 1983 through 1991. Repair 
effects for running emissions are found in EPA report number 
M6.IM.001.

Comments on this report and its proposed use in MOBILE6 should be 
sent to the attention of Janet Kremer.  Comments may be submitted 
electronically to mobile@epa.gov, 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 May 17, 1999. 
Comments will be accepted for sixty (60) days.  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