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Carbon Monoxide (CO) Pollution in Outdoor Air

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

On this page:

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

02/11/2011 – Proposed Decision to Retain the NAAQS for CO

Additional Resources

Fact Sheets and Additional Information Regarding the NAAQS for CO

Scientific and Technical Documents Supporting the NAAQS for CO