What are Class III locations primarily characterized by?

Class III locations are primarily characterized by the presence of ignitable fibers or flyings. These locations typically involve areas where combustible dust or fibers can accumulate, creating an increased risk of fire or explosion when they are suspended in the air.

In the context of the National Electrical Code (NEC), Class III locations require specific safety measures and equipment to minimize hazards associated with these materials. This may include the use of explosion-proof enclosures and special wiring methods to ensure that ignition sources are controlled and that any potential risks are mitigated.

The other options do not accurately define Class III locations. For instance, Class I locations are associated with flammable gases, which does not apply here. Class II locations pertain to dusts, but since Class III specifically references ignitable fibers or flyings, that is a distinguishing characteristic. Additionally, while there may be a need to account for the absence of explosive substances in some areas, this does not define Class III locations as they focus more on the potential presence of combustible materials. Lastly, the presence of liquid combustibles aligns more with Class I locations, where flammable liquids are the primary concern. Thus, the correct identification of Class III locations emphasizes the specific risks associated with ignitable fibers or flyings.