An official website of the United States government.

Due to a lapse in appropriations, EPA websites will not be regularly updated. In the event of an environmental emergency imminently threatening the safety of human life or where necessary to protect certain property, the EPA website will be updated with appropriate information. Please note that all information on the EPA website may not be up to date, and transactions and inquiries submitted to the EPA website may not be processed or responded to until appropriations are enacted.

We've made some changes to If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

Ozone Designations

Partial Designations for the 2015 Ozone Standards

EPA is taking the next step in the Clean Air Act process to implement the national air quality standards for ozone set in 2015.  The Agency finds that most areas in the country meet the standards and is designating these areas “attainment/unclassifiable.”

Notice:  Air Quality Designations for the 2015 Ozone National Ambient Air Quality Standards

See other area designations for the 2015 Ozone Standards

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.