The US EPA has announced a new one-hour national air quality standard for nitrogen dioxide (NO2) of 100/ppb. The EPA is also retaining the existing annual average standard of 53ppb. The EPA is establishing new monitoring requirements in urban areas that will measure NO2 levels around major roads & across the community. Monitors must be located near roadways in cities with 500,000 residents, while larger cities & areas with major roadways will have additional monitors. Community-wide monitoring will continue in cities with at least 1M residents. Working with the States, the EPA will site at least 40 monitors in locations that are susceptible to elevated levels of NO2. The agency expects to identify or designate areas not meeting the new standard, based on existing community-wide monitoring network, by Jan/12. Further information is available from: www.epa.gov/air/nitrogenoxides
