Product Manual

Explosion Proof motors meet Under-
writers Laboratories or CSA standards for
use in the hazardous (explosive) locations
shown by the UL/CSA label on the motor.
The motor user must specify the explosion
proof motor required. Locations are
considered hazardous because the
atmosphere contains or may contain gas,
vapor, or dust in explosive quantities. The
National Electrical Code (NEC) divides these locations into classes and
groups according to the type of explosive agent. The following list has
some of the agents in each classification. For a complete list, see Article
500 of the National Electrical Code.
Class I (Gases, Vapors)
Group A Acetylene
Group B Butadiene, ethylene oxide, hydrogen,
propylene oxide
Group C Acetaldehyde, cyclopropane, diethlether,
ethylene, isoprene
Group D Acetone, acrylonitrile, ammonia, benzene,
butane, ethylene dichloride, gasoline,
hexane, methane, methanol, naphtha,
propane, propylene, styrene, toluene, vinyl
acetate, vinyl chloride, xylene
Class II (Combustible Dusts)
Group E Aluminum, magnesium and other metal
dusts with similar characteristics
Group F Carbon black, coke or coal dust
Group G Flour, starch or grain dust
The motor ambient temperature is not to exceed +40°C or -25°C unless the
motor nameplate specifically permits another value. LEESON explosion
proof motors are approved for all classes noted except Class I,
Groups A & B.
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