U.S. Environmental Protection Agency
Office of Transportation and Air Quality

November 2001

Document Released for Public Information

"Accounting for the Tier 2 and Heavy-Duty 2005/2007
 Requirements in MOBILE6"

Final Report     EPA420-R-01-057      (M6.EXH.004)

Author: John Koupal


ABSTRACT

     The Office of Transportation and Air Quality, Assessment and
Standards Division announces the release of "Accounting for the
Tier 2 and Heavy-Duty 2005/2007 Requirements in MOBILE6" for
public information.  This document EPA420-R-01-057, also known as
M6.EXH.004, is available at the MOBILE6 section of the OTAQ Web
Site (http://www.epa.gov/otaq/m6.htm).

     This report details how MOBILE6 accounts for the effects of
the Tier 2 vehicle and fuel program for light-duty vehicles, and
new standards for heavy-duty vehicles beginning as required under
two recently finalized regulations known as the "Heavy-Duty 2005
rule" and the "Heavy-Duty 2007 rule".  The focus of this report
is to present the methodology for implementing these requirements
in MOBILE6, and contains only a brief overview of each
requirement.  The requirements themselves should be consulted for
an in-depth treatment of the rule provisions, and for background
on the terminology applied in the rules.