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  1. Home
  2. Carbon Monoxide (CO) Pollution in Outdoor Air

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

On This Page: 
  • What are CO standards?
  • How are the standards developed and reviewed?
  • What scientific and technical information supports reviews?

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.

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.

  • Learn more about the standards review process
  • View a timeline of the CO NAAQS to get an overview of how the standards have changed over time

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.

  • See scientific and technical documents from review of the CO NAAQS

Carbon Monoxide (CO) Pollution in Outdoor Air

  • Carbon Monoxide (CO) Basics
  • Setting & Reviewing CO Outdoor Air Standards
  • CO Standard Regulatory Actions
  • Implementing CO Outdoor Air Standards
  • Implementation Data and Reports
  • Other Criteria Air Pollutants
Contact Us about Carbon Monoxide (CO) Pollution
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on December 31, 2024
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