Which classification describes locations where combustible fibers may be present?

• A. Class I, Div 1
• B. Class II, Div 2
• C. Class III, Div 1
• D. Class III, Div 2

Answer: (C)

Fibers that can ignite are placed in Class III locations. This category covers easily ignitable fibers or flyings, such as textile fibers, that could become airborne and ignite under the right conditions. The division part splits further: Division 1 means those fibers may be present in the air during normal operation, so equipment must be designed to handle that risk. Division 2 means fibers are present but not normally airborne in ignitable quantities.

So, when describing locations where combustible fibers may be present, the appropriate classification is Class III, Division 1. This differs from Class I (gases or vapors) and Class II (combustible dust), which address entirely different hazards.