NEC's Classification of Hazardous Atmospheres

Article 500 have classified the hazardous locations are locations where fire or explosion hazards may be exist due to the flammable gases or vapors, flammable liquids, combustible dust, or ignitible fibers or flyings. This publication covers the requirement for electrical and electronic and wiring for all voltage in these areas according to the North America standard requirement.

NEC's Classification of Hazardous Atmospheres