2010 Primary National Ambient Air Quality Standards (NAAQS) for Nitrogen Dioxide
Rule Summary
In 2010, based on its review of the air quality criteria for oxides of nitrogen and the primary NAAQS for oxides of nitrogen as measured by nitrogen dioxide (NO2), EPA made revisions to the primary NO2 NAAQS in order to provide requisite protection of public health.
Specifically, EPA established a new 1-hour standard at a level of 100 ppb. This is based on the 3-year average of the 98th percentile of the yearly distribution of 1-hour daily maximum concentrations, to supplement the previously existing annual standard.
EPA also established requirements for an NO2 monitoring network that now includes both monitors at locations where maximum NO2 concentrations are expected to occur (such as near major roadways), and monitors sited to measure the area-wide NO2 concentrations that occur more broadly across communities.
Rule History
Additional Resources
Final Regulatory Impact Analysis (RIA) for the NO2 National Ambient Air Quality Standards (NAAQS)
Scientific and Technical Documents Supporting the Primary NAAQS for NO2
Related Rules
Revision to the Near-Road Nitrogen Dioxide Monitoring Requirements
03/14/2013 – Final Rule; Revision to Ambient Nitrogen Dioxide Monitoring Requirements
10/19/2012 – Proposed Revisions to Ambient Nitrogen Dioxide Monitoring Requirements