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.
Fact Sheet: National Ambient Air Quality Standards for Carbon Monoxide – Final Rule (PDF)(4 pp, 36 K,
August 12, 2011)
This fact sheet provides an overview of the 2011 decison to retain the CO NAAQS, as well as revisions to the monitoring requirements for CO.
- Carbon Monoxide Monitoring Requirement Would Place One CO Near-Road Monitor in Each of These Large Urban Areas (PDF)(2 pp, 93 K, February 2011)
- Final Map of Carbon Monoxide Near-Road Monitors for Large Urban Areas (PDF)(1 pg, 151 K, August 2011)