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  1. Home
  2. Carbon Monoxide (CO) Pollution in Outdoor Air

National Ambient Air Quality Standards (NAAQS) for Carbon Monoxide (CO)

National Ambient Air Quality Standards (NAAQS) for Carbon Monoxide (CO)
Basic Information
Federal Register Citations
  • 76 FR 54294
  • 76 FR 8158
Docket Numbers
  • EPA-HQ-OAR-2008-0015

On this page:

  • Rule Summary
  • Rule History
  • Additional Resources

Rule Summary

In 2011, based on the Environmental Protection Agency's (EPA) review of the air quality criteria for CO, EPA issued a decision to retain the existing NAAQS for CO.

Rule History

08/31/2011 – Final Decision to Retain the NAAQS for CO (pdf) (2.3 MB)

02/11/2011 – Proposed Decision to Retain the NAAQS for CO (pdf) (2.4 MB)

Additional Resources

Fact Sheets and Additional Information Regarding the NAAQS for CO

Scientific and Technical Documents Supporting the NAAQS for CO

Carbon Monoxide (CO) Pollution in Outdoor Air

  • Carbon Monoxide (CO) Basics
  • Setting & Reviewing CO Outdoor Air Standards
  • CO Standard Regulatory Actions
  • Implementing CO Outdoor Air Standards
  • Implementation Data and Reports
  • Other Criteria Air Pollutants
Contact Us about Carbon Monoxide (CO) Pollution
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on May 29, 2025
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