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Reviewing National Ambient Air Quality Standards (NAAQS)

Sulfur Dioxide (SO2) Primary Air Quality Standards

The Clean Air Act requires EPA to set national ambient air quality standards (NAAQS) for sulfur dioxide and five other pollutants considered harmful to public health and the environment (the other pollutants are ozone, particulate matter, nitrogen dioxide, carbon monoxide, 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.

Documents from Current Review

Documents from Previous Reviews