Release of the Policy Assessment for the Review of the Primary National Ambient Air Quality Standards for Oxides of Nitrogen

The Environmental Protection Agency (EPA) is announcing the availability of the final document titled Policy Assessment for the Review of the Primary National Ambient Air Quality Standards for Oxides of Nitrogen (NO2 PA). Nitrogen dioxide (NO2) is the component of oxides of nitrogen (NOX) for which we have the greatest concern for public health. Accordingly, the current primary (health-based) National Ambient Air Quality Standards (NAAQS) for NOX are in terms of NO2. The NO2 PA presents considerations and conclusions relevant for the EPA's review of the primary NO2 NAAQS. The primary NO2 NAAQS are set to protect the public health from exposures to NO2 in ambient air.