CSLB C-46 Solar ContractorSafetyMedium
An electrical hazard assessment for a commercial solar installation reveals the potential for arc flash. Which of the following PPE categories, as defined by NFPA 70E, would be required for a task with an arc flash incident energy of 9 cal/cm²?
- ACAT 4
- BCAT 1
- CCAT 3
- DCAT 2
Show answer & explanationAnswer & explanation
Correct answer: C. CAT 3
NFPA 70E outlines arc flash PPE categories based on incident energy. An incident energy of 9 cal/cm² falls into Arc Flash PPE Category 3, which requires flame-resistant clothing with an Arc Thermal Performance Value (ATPV) of at least 25 cal/cm².
Why the other options are wrong
- A. CAT 4 is for incident energy levels up to 40 cal/cm².
- B. CAT 1 typically covers incident energy levels up to 4 cal/cm².
- D. CAT 2 typically covers incident energy levels up to 8 cal/cm².
NFPA 70E Arc Flash PPE Categories
NFPA 70E categorizes arc flash hazards and specifies corresponding PPE based on calculated incident energy levels to protect workers from burns.
- Categories (CAT 1-4) correlate to incident energy (cal/cm²).
- PPE must meet or exceed the Arc Thermal Performance Value (ATPV) for the category.
- A full arc flash risk assessment is required to determine the category.
Memory trick: Each cal/cm² is a 'CAT' step up, protecting you from arc flash's hot cup!