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Ground-level Ozone Pollution

Ozone National Ambient Air Quality Standards (NAAQS)

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Rule Summary

On July 13, 2020, based on a review of the full body of currently available scientific evidence and exposure/risk information, the EPA proposed to retain the existing ozone NAAQS. EPA’s proposal is based on its judgment that the current NAAQS protect the public health, with an adequate margin of safety, including the health of at-risk populations with asthma, and protect the public welfare from adverse effects. The existing primary and secondary standards, established in 2015, are 0.070 parts per million (ppm), as the fourth-highest daily maximum 8-hour concentration, averaged across three consecutive years.

Rule History

Additional Resources

Related Rules