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 EPA.gov. 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

EPA Responds to Recommendations for the 2015 Ozone Standards

On December 22, 2017, EPA responded to state and tribal recommendations by indicating the anticipated area designations for the portions of the country not already designated for the 2015 ozone standards.  These responses will start a 120-day period for states and tribes to provide additional information before EPA determines the final designations.  EPA will also be opening a 30-day comment period for the public to provide input on these designations before they are finalized.  For next steps, EPA will continue to work closely with our partners at the state, tribal, and local levels to finalize these area designations and improve ozone air quality.

Read EPA's responses to states and tribes as well as accompanying technical support documents.

Read the Notice of Availability and Public Comment Period

See a Summary of EPA's Response to State and Tribal Recommendations on Area Designations