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This is not the current EPA website. To navigate to the current EPA website, please go to www.epa.gov. 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 This website is no longer updated and links to external websites and some internal pages may not work.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 »

Air Quality Analysis

This site provides information for air quality data analysts inside and outside EPA. Much of the information is in the form of documented analyses that support EPA's National Ambient Air Quality Standards (NAAQS) reviews. The site also contains other documented analyses of special interest.