# Official Release of the MOBILE6.2 Motor Vehicle Emissions Factor Model and the December 2003 AP-42 Methods for Re-Entrained Road Dust > **Rule** · Notice of availability. · Published 2004-05-19 · Effective 2004-05-19 · 69 FR 28830 ## Document - **Document number:** 04-11340 - **Category:** air-emissions - **Federal Register citation:** 69 FR 28830 - **CFR reference:** 40 CFR 51 - **Publication date:** 2004-05-19 - **Effective date:** 2004-05-19 - **EPA docket:** FRL-7663-6 ## Abstract EPA is approving and announcing the availability of the MOBILE6.2 motor vehicle emissions factor model for official use in particulate matter (PM10 and PM2.5) SIPs and transportation conformity determinations outside of California. MOBILE6.2 is an update to MOBILE6 which adds the capability to estimate direct exhaust and brake and tire wear particulate matter emission factors for PM10 and PM2.5, and exhaust emission factors for particulate precursors to the MOBILE6 model. MOBILE6.2 is a substantial improvement over previous methods for estimating PM emissions and incorporates EPA's most current estimates of PM emissions for use by state and local governments to meet Clean Air Act requirements. EPA is also approving and announcing the availability of new methods for the estimation of re-entrained road dust emissions from cars, trucks, buses, and motorcycles on paved and unpaved roads for PM10 and PM2.5 state implementation plans (SIPs) and transportation conformity analyses. These new methods are incorporated in the December 2003 edition of Chapter 13 of Compilation of Air Pollutant Emission Factors, AP-42, Fifth Edition, Volume I: Stationary Point and Area Sources. Today's action also starts time periods after which MOBILE6.2 and the December 2003 AP-42 methods are required to be used in new transportation conformity analyses for PM10 emissions. EPA strongly encourages areas to use the interagency consultation process to examine how MOBILE6.2 and the December 2003 AP-42 methods will affect future transportation conformity analyses, so, if necessary, PM10 SIPs and motor vehicle emissions budgets can be revised with MOBILE6.2 and AP-42 or transportation plans and programs can be revised as appropriate prior to the end of the conformity grace period. ## Source - [Federal Register document](https://www.federalregister.gov/documents/2004/05/19/04-11340/official-release-of-the-mobile62-motor-vehicle-emissions-factor-model-and-the-december-2003-ap-42) --- *AI Analytics · CC0 1.0*