EPA to Reconsider Previous Administration’s Decision to Retain 2015 Ozone Standards

EPA will reconsider the 2020 decision to retain 2015 standards, based on the existing scientific record.

As with the reconsideration of the particulate matter National Ambient Air Quality (NAAQS), EPA will reconsider the decision to retain the ozone NAAQS in a manner that adheres to rigorous standards of scientific integrity and provides ample opportunities for public input and engagement.

This action reflects the Agency’s renewed commitment to a rigorous NAAQS review process, with a focus on protecting scientific integrity.   EPA will ensure the Clean Air Scientific Advisory Committee (CASAC) is fully equipped to advise the Administrator and will reinstall an ozone CASAC panel to provide targeted expertise and advice, as requested by the CASAC itself.

EPA established the current standards at a level of 70 parts per billion in 2015 and retained them in 2020.  EPA has received numerous legal challenges to the 2020 decision.  In addition, the 2020 review was completed without the benefit of an ozone-specific panel supporting the Clean Air Scientific Advisory Committee. 

Background

While ozone levels have fallen by more than 20 percent over the past 20 years, about 100 counties have measured ozone levels above the 2015 standards. The Agency is working closely with State, Tribal, and local air agencies to ensure appropriate area designations and nonattainment area classifications are in place.  In addition, EPA will continue to ensure that State, Tribal, and local air agencies comply with applicable planning and control requirements in order to attain and maintain the 2015 standards, while this reconsideration is underway.

More information about ground-level ozone and the most recent review of the ozone NAAQS is available at:  https://www.epa.gov/ground-level-ozone-pollution.