MOBILE6 is a highway mobile source emission factor model developed by EPA that calculates factors for NOx (Nitrogen Oxides), VOC (volatile organic compounds) and CO (carbon monoxide) in grams of pollutant per mile traveled. DOTs and MPOs rely on the model to assess the air quality impacts of their transportation plans and projects to meet the requirements of ISTEA (1991) and the Clean Air Act amendments of 1990. The latest version of the model includes emissions factors for particulate matter and components that contribute to secondary formation of fine particulate matter (PM2.5) from exhaust, brake wear, and tire wear. Concerns have been expressed about the accuracy and reliability of the model. The objectives of this effort are to evaluate MOBILE6.1/6.2 for accuracy and to understand and assess the validation of these modules. This will include assessments of the emission factors related to particulate matter, the emission factors related to air toxics, and the emission factors when compressed natural gas (CNG) is specified as the fuel.

Completed; Agency Final Report (1,075 KB, 134 pp.) available in Adobe PDF.