Arc flash hazards are broken down into how many Hazard Risk Categories (HRC)?

Arc flash hazards are broken down into how many Hazard Risk Categories (HRC)?

• A. 2
• B. 3
• C. 5
• D. 4

Answer: (C)

Arc flash hazard levels use five Hazard Risk Categories. The scale runs from 0 to 4, with each category tied to a specific range of incident energy and the minimum PPE required. HRC 0 means no arc flash hazard, while HRC 1 through 4 represent increasing energy levels and protection needs. Because the system includes the zero-hazard level plus four higher levels, there are five categories in total. More or fewer categories would not align with how NFPA 70E defines the protective equipment requirements for arc flash hazards.

Arc flash hazard levels use five Hazard Risk Categories. The scale runs from 0 to 4, with each category tied to a specific range of incident energy and the minimum PPE required. HRC 0 means no arc flash hazard, while HRC 1 through 4 represent increasing energy levels and protection needs. Because the system includes the zero-hazard level plus four higher levels, there are five categories in total. More or fewer categories would not align with how NFPA 70E defines the protective equipment requirements for arc flash hazards.