ICC Electrical Systems and Safety 1 — Questions and Answers
Question 1: Which electrical code serves as the primary reference for wiring installations in Illinois?
- OSHA 1910
- National Electrical Code (NEC) (Correct answer)
- ICC Mechanical Code
- Illinois Fire Prevention Code
Correct answer: National Electrical Code (NEC)
The National Electrical Code (NEC) is the standard reference adopted in Illinois for all electrical wiring and installation work.
Question 2: What is the required minimum clearance between overhead electrical lines and residential rooftops in Illinois?
- 3 feet
- 8 feet (Correct answer)
- 10 feet
- 15 feet
Correct answer: 8 feet
The NEC and Illinois requirements mandate at least 8 feet of vertical clearance above rooftops for service-entrance conductors.
Question 3: Which device is required in all new residential bathrooms to protect against electrical shock from ground faults?
- Arc Fault Circuit Interrupter (AFCI)
- Ground Fault Circuit Interrupter (GFCI) (Correct answer)
- Surge protector
- Standard 15A breaker
Correct answer: Ground Fault Circuit Interrupter (GFCI)
GFCI outlets or breakers are required in bathrooms, kitchens, and other wet locations to prevent potentially fatal electrical shocks.
Question 4: When working near energized electrical equipment, Illinois contractors must follow which safety standard?
- NFPA 13
- OSHA 29 CFR 1910.333 (Electrical Safety) (Correct answer)
- ICC A117.1
- ASHRAE 90.1
Correct answer: OSHA 29 CFR 1910.333 (Electrical Safety)
OSHA 29 CFR 1910.333 establishes safety-related work practices that apply when working on or near energized electrical equipment.
Question 5: What color is the grounding conductor in a standard U.S. electrical system?
- White
- Black
- Red
- Green or bare copper (Correct answer)
Correct answer: Green or bare copper
Grounding conductors are identified by green insulation or left as bare copper wire to distinguish them from current-carrying conductors.
Question 6: An ICC contractor discovers aluminum wiring in an older Illinois home. The recommended action is to:
- Leave it as-is since it is grandfathered
- Use approved anti-oxidant compound and CO/ALR-rated devices (Correct answer)
- Cover it with electrical tape
- Immediately disconnect all power permanently
Correct answer: Use approved anti-oxidant compound and CO/ALR-rated devices
Aluminum wiring requires anti-oxidant compound and CO/ALR-rated devices to prevent overheating and fire hazards.
ICC Electrical Systems and Safety 1
Which electrical code serves as the primary reference for wiring installations in Illinois?