ANSWERS TO YOUR MOST FREQUENTLY ASKED QUESTIONS
Q: What is NOx?
A: Nitrogen oxides, or NOx, is the generic term for a group of highly reactive gases, all of which contain nitrogen and oxygen in varying amounts. Many of the nitrogen oxides are colorless and odorless. However, one common pollutant, nitrogen dioxide (NO2) along with particles in the air can often be seen as a reddish-brown layer over many urban areas.
Q: Where does NOx come from?
A: Nitrogen oxides form when fuel is burned at high temperatures, as in a combustion process. The primary sources of NOx are motor vehicles, electric utilities, and other industrial, commercial and residential sources that burn fuels.
Q: What is being done to control the transport of pollution?
A: For some time, EPA has recognized that pollutant transport can impair an area's ability to meet air quality standards. As a result, in March 1995 a collaborative, Federal-state process to assess the ozone transport problem was begun. Through a two-year effort known as the Ozone Transport Assessment Group (OTAG), EPA worked in partnership with the 37 easternmost states and the District of Columbia, industry representatives, academia, and environmental groups to develop recommended strategies to address transport of ozone-forming pollutants across state boundaries.