An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Text Version of Infographic

See inforgrpahic.

Sources of air pollution cause smog, soot, health and welfare impacts.

Carbon dioxide (C02) and other greenhouse gases affect climate change.

Sources of air pollution are onroad vehicles and engines (light-duty vehicles, heavy duty vehicles, and motorcycles) and nonroad vehicles and engines (aircraft, nonroad diesel equipment, marine engines, ocean vessels, locomotives, lawn and garden equipment, recreation vehicles.

Solutions for transportation air pollution, emission reductions, can lead to cleaner air and better health.

Catalytic converters in conjunction with unleaded gasoline and low sulfur levels significantly reduce hydrocarbon and nitrogen oxide emissions

Fuel standards reduce exposure to pollutants like lead and benzene. Renewable fuels reduce CO2 emissions.

Engine technologies like computer controls, variable valve timing, multi-valve engines, turbo charging and gasoline direct injection improve fuel economy and reduce CO2 emissions.

Transmission technologies like 7+ speeds, dual clutch transmissions, (DCTs), and continuously variable transmissions (CVTs) improve fuel economy and reduce CO2 emissions.

Diesel filters reduce particulate matter from on road and off road diesel engines.

Alternative vehicle technologies like plug-in electric vehicles and fuel cells equals zero tailpipe emissions

Better transportation planning for passengers and freight reduce emissions and fuel use.