Which of the following classifications is specifically used for locations with easily ignitable fibers?

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

Answer: (D)

The big idea is how hazardous locations are categorized by the type of hazard and whether that hazard is present under normal operation or only under abnormal conditions. For easily ignitable fibers, the relevant class is Class III. Within that class, Division 2 is used when those fibers are not normally in the air in sufficient quantities to form an ignitable mixture, but could be present under abnormal conditions. So, locations with easily ignitable fibers that aren’t routinely in the air fall under Class III, Division 2. This distinguishes them from areas where fibers are normally present (Division 1) or from other hazards like gases/vapors (Class I) or dusts (Class II).