American National Standards Institute, American National Standards Institute, National Fire Protection Association (Estados Unidos), & National Fire Protection Association (Estados Unidos). (2008). Recommended practice for the classification of flammable liquids, gases, or vapors and of hazardous (classified) locations for electrical installations in chemical process areas: NFPA 497 (2008 edition.). Quincy, Mass.: National Fire Protection Association.
Citación estilo ChicagoAmerican National Standards Institute, American National Standards Institute, National Fire Protection Association (Estados Unidos), y National Fire Protection Association (Estados Unidos). Recommended Practice for the Classification of Flammable Liquids, Gases, or Vapors and of Hazardous (classified) Locations for Electrical Installations in Chemical Process Areas: NFPA 497. 2008 edition. Quincy, Mass.: National Fire Protection Association, 2008.
Cita MLAAmerican National Standards Institute, American National Standards Institute, National Fire Protection Association (Estados Unidos), y National Fire Protection Association (Estados Unidos). Recommended Practice for the Classification of Flammable Liquids, Gases, or Vapors and of Hazardous (classified) Locations for Electrical Installations in Chemical Process Areas: NFPA 497. 2008 edition. Quincy, Mass.: National Fire Protection Association, 2008.