News

EPA Proposes to Retain 2010 Air Quality Standard for Nitrogen Dioxide

Country Expected to Remain in Compliance

The U.S. Environmental Protection Agency (EPA) recently closed its required review of air quality studies and data and , without revision, for oxides of nitrogen and nitrogen dioxide (NO2).  EPA concluded that the standards, last revised in 2010, are adequate to protect public health.  As the entire nation is 鈥渃ompliant鈥 with the 2010 standards, states and industries are not expected to have to contend with the repercussions of 鈥渘onattainment.鈥  A more stringent standard could have pushed areas into 鈥渘onattainment,鈥 which puts highway/transit funding and new construction in jeopardy. 

51风流 reported back in April 2012 that EPA had designated the entire nation as 鈥渃ompliant鈥 the 2010 National Ambient Air Quality Standards (NAAQS) for nitrogen dioxide (NO2).  However, 51风流 warned that EPA may take steps to re-designate areas at a later date because of a new roadside air quality monitoring network that was to be in place by 2013.  51风流 also reported in January 2017 in favor of a newly finalized EPA rule to relax a mandate for smaller cities to install near-road NO2 emissions monitoring stations. 

Visit EPA鈥檚 鈥淕reen Book鈥 online at to access maps of areas of the country where air pollution levels persistently exceed NAAQS and may be classified as nonattaiment areas. 

The Clean Air Act requires EPA to review air quality data and the standards every five years.  (EPA had missed the most recent deadline, and environmental groups sued the agency to complete its review.)  Comments on this proposed rule are due on or before September 25, 2017. 

For more information, please contact Leah Pilconis at pilconisl@agc.org.