U.S. Environmental Protection Agency

April 2001

Document Released for Public Information

"Determination of CO Basic Emission Rates, OBD and
I/M Effects for Tier 1 and Later LDVs and LDTs" 

Report Number   EPA420-R-01-032     (M6.EXH.009)
 
	The Office of Transportation and Air Quality, Assessment and 
Standards Division announces the release of "Determination of CO Basic 
Emission Rates, OBD and I/M Effects for Tier 1 and Later LDVs and LDTs" for public 
information.  This document EPA420-R-01-032, also known as M6.EXH.009, 
is available at the MOBILE6 section of the OTAQ Web Site 
(http://www.epa.gov/otaq/m6.htm).

	This document describes the data that was used, and the methodology and analysis 
that was done to calculate Carbon Monoxide emission factors for Tier1 and later cars and 
light trucks.  The CO emission factors that are used in MOBILE6.0 are presented in
this report.

	This report was originally released (as a draft) in 1999,
and then revised in March, 2001.  This current version is the final revision of the
March, 2001 draft (of M6.EXH.009).  This final revision incorporates suggestions 
and comments received from stakeholders during the 60-day review period and from peer 
reviewers.