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EPA's Transportation and Air Quality program protects public health and the environment by regulating air pollution from motor vehicles, engines, and the fuels used to operate them, and by encouraging travel choices that minimize emissions. These "mobile sources" include cars and light trucks, heavy trucks and buses, nonroad recreational vehicles (such as dirt bikes and snowmobiles), farm and construction machines, lawn and garden equipment, marine engines, aircraft, and locomotives.

Transportation and Air Quality Key Topics:

Overview:  Pollutants and Programs:  Information on how much air pollution and greenhouse gases are emitted by mobile sources, the programs OTAQ has undertaken to control these emissions, and the impact of those programs on air quality and climate change.

Consumer Information:  Learn what you can do to help reduce air pollution and how to buy the cleanest, most fuel-efficient vehicle that meets your needs.

Motor Vehicles and Engines:  Information about highway vehicles (cars and light trucks, heavy trucks, buses, engines, and motorcycles): fuel economy, emission standards and regulations, emission recall programs, new vehicle certification and in-use vehicle compliance, inspection and maintenance programs, diesel retrofit programs, evaluating the benefits of inventions designed to reduce emissions, and importing vehicles to the United States.

Nonroad Engines, Equipment, and Vehicles:  Information about aircraft, locomotives, diesel and gasoline boats and ships, personal watercraft, lawn and garden equipment, agricultural and construction machines, and recreational vehicles (such as dirt bikes and snowmobiles): emission standards and regulations, certification and compliance, and diesel retrofit programs.

Fuels and Fuel Additives:  Information on diesel, gasoline, and alternative fuels for mobile sources, fuel-quality control programs, requirements for registration and health effects testing of new fuels or fuel additives, and reporting forms.

Partnerships:  Information about our partnerships to reduce air pollution associated with transportation and other mobile sources. These programs include commuter choice, diesel retrofit, buying a cleaner car or truck, and other initiatives.

State and Local Transportation Resources:  Information on the ties between land use, transportation planning, and air quality. Topics includes conformity, State Implementation Plans, transportation control measures, and available funding and grants for implementation of such programs.

Modeling, Testing, and Research:  Information on OTAQ models for estimating emissions from highway vehicles, nonroad sources, and fuels; how EPA tests and measures emissions; and OTAQ research into advanced technologies.

For help on finding information on the OTAQ Web site, please contact us.

This page is maintained by EPA's Office of Transportation and Air Quality (OTAQ).
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