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The exhaust fans on this page are sturdily constructed, direct drive, horizontal discharge fans that are typically use for general ventilation of factories, garages, warehouses and other industrial, commercial & agricultural building applications.
All of the hazardous location or intrinsically safe exhaust fan have a single speed explosion proof motor.
• Totally enclosed, ball bearing motor with thermal overload protection.
• The fan blades are well-balanced, heavy gauge aluminum.
• Heavy wire chrome plated OSHA guards on intake side of fan.
• All fans are shipped completely assembled.
CLASS I, GROUP C Atmospheres containing ethyl ether, ethylene, gases or vapors of equivalent hazard.
CLASS I, GROUP D Atmospheres such as acetone, ammonia, benzene, butane, cyclopropane, ethanol, gasoline, hexane, methane, natural gas, naphtha, propane, or gasses or vapors of equivalent hazard.
CLASS II GROUP F Atmospheres containing carbonaceous dust, including carbon black, charcoal, coal, or coke dusts that have more than 8% total entrapped volatiles, or dusts that have been sensitized by other materials so that they present an explosion hazard.
CLASS II GROUP G Atmospheres containing combustible dusts not included in group E or F, including flour, grain, wood, plastic and chemicals.
** Please see individual manufacturer's motor specs to confirm which class is covered.
While no explosion proof wall exhaust fan is considered to be 100% explosion proof, the combination of explosion proof motors and non sparking aluminum propellers help minimize the likely hood of a fire or explosion caused by the fan.
AMCA code 99-0401 addresses spark resistance in terms of assembly of fan components. There are generally three types of spark resistant construction:
TYPE A:
This is the highest degree of spark resistance - the air stream parts of the fan are made out of non-ferrous material (materials whose whose iron contact is less than 5%). Aluminum is typically the non-ferrous materials used but other materials such as Monel®, Inconel® and Hastelloy® are used in high heat applications where aluminum is not suitable.
TYPE B:
Less protection than Type A spark resistant construction, AMCA “B” construction consists of a non-ferrous wheel and non -ferrous rubbing plate around the hole through which the shaft passes. As with AMCA “A” construction, aluminum in usually the non-ferrous material of choice but can be substituted with the alternative materials listed for AMCA “A” construction.
TYPE C:
This is the lowest degree of spark resistance. Utilizes only a non-ferrous rubbing plate that is typically constructed of aluminum but can be constructed out of the aforementioned alternative materials when appropriate.
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