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Green Book - current as of August 31, 2021
The EPA Green Book provides detailed information about area National Ambient Air Quality Standards (NAAQS) designations, classifications and nonattainment status. Information is current as of the Green Book posted date and is available in reports, maps and data downloads.
Select one of the NAAQS below to view information about designated nonattainment areas.
Green Book Website Disclaimer
New features in this Green Book: