An emission control method that involves recirculating exhaust gases from an engine back into the intake andcombustion chambers. This lowers combustion temperatures and reduces NOx. See also: Nitrogen Oxides
California Air Resources Board ARB (California Environmental Protection Agency), glossary of air pollution terms, Sacramento, CA, USA 2013. http://www.arb.ca.gov/html/gloss.htm, (Air Pollut - Amer) {594}