Explosion-Proof, UL Classifications

Class I: Those in which flammable gases or vapors may be present in the air in quantities sufficient to produce explosive or ignitable mixtures.

Class II: Atmospheres that are hazardous because of the presence of combustible dust.

Group C: Atmospheres containing ethyl or ether vapors.

Group D: Atmospheres containing acetone, alcohol, benzene, benzol, butane, gasoline, hexane, lacquer solvent vapors, natural gas, propane, etc.

Group E: Atmospheres containing metal dust, including aluminum, magnesium, or their commercial alloys.

Group F: Atmospheres containing carbon black, charcoal, coal, or coke dust.

Group G: Atmospheres containing chemical dusts, combustible plastics, flour, grain, or starch.