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Carbon Monoxide (CO) Pollution in Outdoor Air

Setting and Reviewing Standards to Control Carbon Monoxide (CO) Pollution in Outdoor Air

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What are CO standards?

National Ambient Air Quality Standards (NAAQS) for CO specify maximum amounts of carbon monoxide to be present in outdoor air. Limiting CO in the air protects human health and the environment.
  • See NAAQS for CO for an in-depth explanation of the current CO standards, including Federal Register citations and fact sheets.

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How are the standards developed and reviewed?

The Clean Air Act requires EPA to set national ambient air quality standards for carbon monoxide as one of the six criteria pollutants. The law also requires EPA to periodically review the standards and revise them if appropriate to ensure that they provide the requisite amount of health and environmental protection and to update those standards as necessary.

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What scientific and technical information supports reviews?

The various documents published during the review process include multiple drafts of plans and assessments, reports from the Clean Air Scientific Advisory Committee (CASAC), and Federal Register notices.

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