Under the Clean Air Act Amendments of 1977, EPA is required to review and if appropriate revise the air quality criteria for the primary (health-based) and secondary (welfare-based) national ambient air quality standards (NAAQS) every 5 years. On October 26, 2015, EPA published a final rule revising the NAAQS for ozone to provide increased protection for public health and welfare. The current review will include the preparation by EPA of an Integrated Review Plan, an Integrated Science Assessment, and also a Policy Assessment, which includes a risk/exposure assessment, with opportunities for review by EPA's Clean Air Scientific Advisory Committee and the public. These documents inform the Administrator's proposed decision as to whether to retain or revise the current standards. This proposed decision will be published in the Federal Register with opportunity provided for public comment. The Administrator's final decisions will take into consideration these documents, CASAC advice, and public comment on the proposed decision.