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Carbon Monoxide (CO) Pollution in Outdoor Air

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

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