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Carbon Monoxide (CO) Pollution in Outdoor Air

Fact Sheets and Additional Information Regarding the National Ambient Air Quality Standards (NAAQS) for Carbon Monoxide (CO)

On August 31, 2011, after carefully reviewing the most recent available scientific evidence, consulting with the Agency's independent science advisors, and considering public comment, the Environmental Protection Agency (EPA) issued a decision to retain the NAAQS for CO.

This page contains a variety of fact sheets and other documents describing that action.

For more information, visit the CO NAAQS page.

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.