Propellant 3 : A gas with a high vapor pressure used to force formulations out of aerosol spray cans. Among the gases used are butanes, propanes and nitrogen
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}