Reviewing National Ambient Air Quality Standards (NAAQS)

Carbon Monoxide (CO) Air Quality Standards

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

Documents from Current Review

Documents from Previous Reviews