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Under the Clean Air Act, EPA establishes air quality standards to protect public health and the environment. EPA has set national air quality standards for six common air pollutants. These include:

EPA tracks the emissions from the sources of these pollutants, including how much of each pollutant (or the pollutants that form them) is emitted from various pollution sources. EPA posts the results of our analyses to this web site.

Basic Information - Information about air quality standards for the six common air pollutants, also called criteria pollutants and how EPA tracks emissions and their sources.

Air Emissions by Pollutant:

Where You Live - View state, county, and facility-level emission summaries for the six common air pollutants.

Air Quality Trends - EPA also tracks the levels of these pollutants in the ambient air. View current and historical air quality trends.

National Air Toxics Assessments (NATA) - EPA is also working with other Federal, State, local and tribal air quality agencies to achieve reductions in emissions of toxic air pollutants. NATA is EPA's ongoing comprehensive evaluation of air toxics in the U.S.


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