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  2. Reviewing National Ambient Air Quality Standards (NAAQS)

Particulate Matter (PM) Air Quality Standards

The Clean Air Act requires EPA to set national air quality standards for particulate matter and five other pollutants considered harmful to public health and the environment (the other pollutants are ozone, nitrogen oxides, carbon monoxide, sulfur dioxide and lead). The law also requires EPA to periodically review the standards to ensure that they provide adequate health and environmental protection, and to update those standards as necessary. Learn more about the NAAQS review process.

Documents from Current Review

  • Planning Documents
  • Integrated Science Assessments
  • Policy Assessments
  • CASAC Documents
  • Federal Register Notices
  • Response to Comments Document
  • Regulatory Impact Analyses

Documents from Previous Reviews

  • Documents from Review Completed in 2012
  • Documents from Review Completed in 2006
  • Documents from Review Completed in 1997
  • Documents from Reviews Completed Prior to 1997

Announcements

2/7/2024 - EPA strengthens air quality standard for fine particle pollution (PM2.5)

Related Links

  • Air Quality Research
  • Criteria Air Pollutants
  • Table of Current NAAQS
  • Timeline of PM NAAQS
  • Air Quality Analysis
  • Trends and Design Values

Reviewing National Ambient Air Quality Standards (NAAQS)

  • Carbon Monoxide Standards
  • Lead Standards
  • Nitrogen Dioxide Primary Standards
  • Nitrogen Dioxide Secondary Standards
  • Ozone Standards
  • Particulate Matter Standards
  • Sulfur Dioxide Primary Standards
  • Sulfur Dioxide Secondary Standards
Contact Us about Reviewing National Ambient Air Quality Standards (NAAQS)
Contact Us about Reviewing National Ambient Air Quality Standards (NAAQS) to ask a question, provide feedback, or report a problem.
Last updated on January 16, 2025
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