AMCA Fan Classifications

AMCA 99-0401 addresses the choice of materials only in terms of ferrous or non-ferrous.  It is generally accepted practice that ferrous materials are those whose iron content is 5% or greater. The standard further addresses spark resistance in terms of assembly of fan components.  The result is three types of spark resistant construction: 

Type A: 

Type B:   Type C:  
    Offers the "entry level" degree of spark resistant construction, requiring that the fan components be assembled in a manner such as to reduce the possibility of contact between any stationary and rotating component.
These classifications were developed in response to equipment users' need for a way to achieve spark resistance for varying degrees of ignition hazard.  The specific level of resistance necessary is one which only the purchaser can evaluate. The choice of any level of spark resistance should be determined in consultation with the fan manufacturer.  A fan can then be engineered and constructed to meet the required service level. 

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