EETC Electrical Safety & Code Compliance 2 — Questions and Answers
Question 1: Which NEC article specifically covers general requirements for electrical installations?
- Article 90
- Article 100
- Article 110 (Correct answer)
- Article 200
Correct answer: Article 110
NEC Article 110 covers general requirements for electrical installations, including examination, identification, and working space.
Question 2: What is the minimum working clearance in front of a 480V panelboard in a typical commercial installation (Condition 1)?
- 2 feet
- 3 feet (Correct answer)
- 3.5 feet
- 4 feet
Correct answer: 3 feet
NEC 110.26 requires a minimum of 3 feet of working clearance in front of equipment operating at 151–600V under Condition 1.
Question 3: A ground fault circuit interrupter (GFCI) trips when current imbalance between hot and neutral exceeds:
- 1 mA
- 5 mA (Correct answer)
- 10 mA
- 15 mA
Correct answer: 5 mA
GFCI devices are designed to trip at approximately 5 milliamps (4–6 mA range) of ground fault current to prevent electrocution.
Question 4: 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 (CO2, dry chemical) safe for use on energized electrical equipment fires.
Question 5: Under OSHA 1910.333, when must electrical equipment be de-energized before work begins?
- Only when voltage exceeds 600V
- When live parts are exposed and work is within the limited approach boundary (Correct answer)
- Only when the worker lacks PPE
- Whenever the circuit breaker is accessible
Correct answer: When live parts are exposed and work is within the limited approach boundary
OSHA 1910.333 requires de-energizing equipment when employees work on or near exposed live parts within approach boundaries.
Question 6: What does the acronym 'LOTO' stand for in electrical safety procedures?
- Lock Out / Tag Out (Correct answer)
- Line Out / Turn Off
- Load Out / Transfer On
- Limit Output / Test Only
Correct answer: Lock Out / Tag Out
LOTO stands for Lockout/Tagout, the OSHA-required procedure to ensure equipment is de-energized and cannot be re-energized during maintenance.
Question 7: According to NEC 210.8, GFCI protection is required for all 125V, 15A and 20A receptacles in which indoor commercial location?
- Break rooms only
- Bathrooms (Correct answer)
- Private offices
- Server rooms
Correct answer: Bathrooms
NEC 210.8(B) requires GFCI protection for receptacles in commercial bathrooms, among other specified locations.
EETC Electrical Safety & Code Compliance 2
Which NEC article specifically covers general requirements for electrical installations?