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 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 This website is no longer updated and links to external websites and some internal pages may not work.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 Implementation Plans

This site contains information about air quality regulations called State Implementation Plans (SIPs), Federal Implementation Plans (FIPs), and Tribal Implementation Plans (TIPs).


Check Status of a SIP

Find Approved Plans

Basic Information

Rubber stamps showing rules and regulations