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The Clean Air Scientific Advisory Committee (CASAC) provides independent advice to the EPA Administrator on the technical bases for EPA's National Ambient Air Quality Standards.

Meetings and


  • CASAC Reports
    • 05/16/2024 CASAC Advice on the National Ambient Air Quality Standards (NAAQS) Review Process
    • 04/24/2024 Consultation on the EPA’s Integrated Review Plan for the Primary National Ambient Air Quality Standards for Oxides of Nitrogen. Volume 2: Planning for the Review and the Integrated Science Assessment (March 2024)
    • 09/27/2023 CASAC Review of the EPA’s Policy Assessment for the Review of the Secondary National Ambient Air Quality Standards for Oxides of Nitrogen, Oxides of Sulfur and Particulate Matter (External Review Draft – May 2023)
  • Agency Responses
  More Reports and Agency Responses