Mobile sources includes onroad vehicles (e.g., cars, trucks, buses) and offroad sources (e.g, airplanes, boats, and offroad equipment). Mobile sources emit both hazardous and criteria air pollutants, and are defined similarly by Clean Air Act regulatory programs targeting these different kinds of air pollution.
MOBILE SOURCES - HAZARDOUS AIR POLLUTANTS
Scorecard's Hazardous Air Pollutant reports provide information about the amount of toxic chemicals mobile sources release in an area, as well as the resulting exposures and health risks. These reports are based on EPA's National-Scale Air Toxics Assessment, which splits mobile sources into two categories:
Onroad mobile sources: Vehicles found on roads and highways (e.g., cars, trucks, buses).
Nonroad mobile sources: Mobile sources not found on roads and highways (e.g., airplanes, trains, lawn mowers, construction vehicles, farm machinery).
MOBILE SOURCES - CRITERIA AIR POLLUTANTS
Scorecard's Criteria Air Pollutant reports provide information about the amount of criteria pollutants mobile sources release in an area, as well as the resulting exposures and health risks. These reports are based on EPA's National Emissions Trends database. Definitions of EPA's mobile source category are provided in its National Air Pollutant Emissions Trends Report, 1900-1996.
To support Clean Air Act regulations, EPA has assigned Source Classification Categories (SCCs) for air pollution generating activities. These classifications are used to develop estimates and projections of air pollution by pollutant type. Scorecard's Criteria Air Pollutant reports define 'Mobile Sources' as sources with an SCC beginning with 'A22'. Presented below is a brief description of the mobile source categories used by Scorecard:
Highway Vehicles: Gasoline and diesel powered automobiles, buses and trucks.
Marine Vessels: Commercial, military and recreational.
Aircraft and Railroads
Paved and Unpaved Roads
Off-Road Equipment: Gasoline and diesel powered lawn and garden equipment, industrial and recreational engines.
GENERAL MOBILE SOURCE RESOURCES
EPA Office of Transportation and Air Quality
Motor Vehicles and the 1990 Clean Air Act
ONLINE RESOURCES ABOUT SPECIFIC MOBILE SOURCE POLLUTANTS
EPA's Fact Sheets on:
Automobiles and Carbon Monoxide
Automobiles and Ozone
Air Toxics from Motor Vehicles
Greenhouse Gas Emissions from Motor Vehicles
Mobile Source Air Toxic Emissions website provides access to the
agency's 1993 Motor Vehicle-Related Air Toxics Study.
ONLINE RESOURCES ABOUT SPECIFIC MOBILE SOURCE SUBCATEGORIES
Cars: EPA Green Vehicle Guide
EPA/DOE Fuel Economy Guide
Lawn and Garden Equipment