CME Safety Protocols & Hazard Prevention 2

Question 1

What is the minimum approach distance for an unqualified worker near energized 15 kV overhead conductors?

Accepted Answer

10 feet

Answer

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?

Accepted Answer

Category 4

Answer

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?

Accepted Answer

5 mA

Answer

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?

Accepted Answer

Operating it at least 20 feet from building openings

Answer

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?

Accepted Answer

De-energize the equipment

Answer

Equipment must be de-energized before applying lockout devices; verification of zero energy state follows after.

(CME) Certified Master Electrician Practice Test