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Reviewing National Ambient Air Quality Standards (NAAQS)

Ozone (O3) Air Quality Standards

The Clean Air Act requires EPA to set national ambient air quality standards (NAAQS) for ozone and five other pollutants considered harmful to public health and the environment (the other pollutants are particulate matter, nitrogen oxides, carbon monoxide, sulfur dioxide and lead). The law also requires EPA to periodically review the standards to ensure that they provide adequate health and environmental protection, and to update those standards as necessary. Learn more about the NAAQS review process.

Document from Current Review

Documents from Previous Reviews