CME Safety Protocols & Hazard Prevention 2 — Questions and Answers
Question 1: What is the minimum approach distance for an unqualified worker near energized 15 kV overhead conductors?
- 3 feet
- 6 feet
- 10 feet (Correct answer)
- 15 feet
Correct answer: 10 feet
OSHA requires unqualified workers to maintain at least 10 feet from energized lines up to 50 kV.
Question 2: Which PPE category under NFPA 70E requires arc-rated clothing with a minimum arc rating of 40 cal/cm²?
- Category 1
- Category 2
- Category 3
- Category 4 (Correct answer)
Correct answer: Category 4
NFPA 70E PPE Category 4 requires arc-rated clothing with a minimum arc rating of 40 cal/cm².
Question 3: A ground fault circuit interrupter (GFCI) trips when leakage current exceeds which threshold?
- 1 mA
- 5 mA (Correct answer)
- 15 mA
- 30 mA
Correct answer: 5 mA
GFCI devices are designed to trip at 4–6 mA (nominally 5 mA) to protect against electrocution.
Question 4: When using a portable generator on a job site, which safety measure is MOST critical to prevent carbon monoxide poisoning?
- Connecting it to a GFCI receptacle
- Operating it at least 20 feet from building openings (Correct answer)
- Using only 12 AWG extension cords
- Installing a transfer switch
Correct answer: Operating it at least 20 feet from building openings
Generators must be kept at least 20 feet from doors, windows, and vents to prevent CO buildup inside structures.
Question 5: Under OSHA's lockout/tagout standard, which step must occur BEFORE applying the lockout device?
- Verify zero energy state
- Notify affected employees
- De-energize the equipment (Correct answer)
- Release stored energy
Correct answer: De-energize the equipment
Equipment must be de-energized before applying lockout devices; verification of zero energy state follows after.
Question 6: Which class of fire extinguisher is appropriate for energized electrical equipment fires?
- Class A
- Class B
- Class C (Correct answer)
- Class D
Correct answer: Class C
Class C extinguishers use non-conductive agents suitable for energized electrical equipment fires.
Question 7: According to OSHA 1926.502, safety nets must be installed when workers are exposed to falls of more than how many feet and guardrails or personal fall arrest systems are not feasible?
- 4 feet
- 6 feet (Correct answer)
- 10 feet
- 15 feet
Correct answer: 6 feet
OSHA's construction standard requires fall protection — including safety nets — for falls greater than 6 feet.
CME Safety Protocols & Hazard Prevention 2
What is the minimum approach distance for an unqualified worker near energized 15 kV overhead conductors?