InterNACHI Electrical Systems and Safety 5 — Questions and Answers
Question 1: What is the required arc-fault circuit interrupter (AFCI) protection for bedroom circuits in homes built to current NEC standards?
- AFCI protection is optional in bedrooms
- AFCI protection is required only in homes over 2,000 square feet
- AFCI protection is required for all 120V, 15- and 20-amp branch circuits in bedrooms (Correct answer)
- AFCI protection is required only for circuits with more than four outlets
Correct answer: AFCI protection is required for all 120V, 15- and 20-amp branch circuits in bedrooms
The NEC requires AFCI protection for all 120V, 15- and 20-amp branch circuits in bedrooms to reduce fire risk from arc faults in cords and wiring.
Question 2: When inspecting a garage, an inspector finds an outlet within 6 feet of a vehicle door that is not GFCI-protected. What is the correct assessment?
- Acceptable if the garage was built before 1978
- A deficiency, as all garage outlets require GFCI protection regardless of location (Correct answer)
- Only outlets near water sources require GFCI in a garage
- Acceptable if the outlet is on a 20-amp circuit
Correct answer: A deficiency, as all garage outlets require GFCI protection regardless of location
All receptacles in garages (except dedicated appliance circuits) require GFCI protection per NEC requirements, regardless of their location within the garage.
Question 3: An inspector discovers that the grounding electrode conductor at the main panel is a #6 AWG copper wire connected to a metal water pipe. What should be noted if the water pipe is plastic near the street?
- The grounding system is fully adequate as long as any metal pipe exists
- The grounding system may be compromised if the metallic water pipe section is short and discontinuous (Correct answer)
- Plastic pipe replacements have no effect on grounding systems
- Grounding to water pipes is no longer permitted under any circumstance
Correct answer: The grounding system may be compromised if the metallic water pipe section is short and discontinuous
If a plastic section interrupts the metal water pipe before reaching earth, the pipe segment cannot serve as a grounding electrode and the system is compromised.
Question 4: Which of the following best describes the function of a whole-house surge protector installed at the main electrical panel?
- It prevents all circuit breakers from tripping during power surges
- It diverts excess voltage from transient surges to protect connected devices (Correct answer)
- It monitors amperage draw and shuts off power during overloads
- It replaces the need for GFCI and AFCI protection
Correct answer: It diverts excess voltage from transient surges to protect connected devices
A whole-house surge protector diverts excess transient voltage to ground, reducing the risk of surge damage to sensitive electronics throughout the home.
Question 5: What is the concern when a home inspector finds multiple extension cords being used as permanent wiring in a bedroom?
- Extension cords are acceptable as permanent wiring if they are heavy-duty rated
- Extension cords used as permanent wiring are a fire and shock hazard and indicate insufficient outlets (Correct answer)
- Extension cords are only a concern in kitchens and bathrooms
- Extension cords used indoors pose no safety risk
Correct answer: Extension cords used as permanent wiring are a fire and shock hazard and indicate insufficient outlets
Extension cords are not designed for permanent use, can overheat, and their use indicates a need for additional permanently wired outlets.
Question 6: During an exterior inspection, an inspector finds service drop conductors with less than 10 feet of clearance above a driveway used by vehicles. What is the correct finding?
- Acceptable for residential driveways regardless of vehicle height
- A potential safety hazard — service drop clearance should be at least 10 feet over driveways not used by trucks (Correct answer)
- Service drop clearance is the utility company's responsibility and should not be reported
- Only a concern if the conductors are bare copper
Correct answer: A potential safety hazard — service drop clearance should be at least 10 feet over driveways not used by trucks
NEC requires a minimum 10-foot clearance for service conductors over driveways accessible to pedestrians but not trucks; inadequate clearance is a safety hazard.
Question 7: What condition is indicated when a home inspector tests a GFCI outlet and the reset button does not pop out after pressing the test button?
- The GFCI is functioning correctly and does not need to trip
- The GFCI device has failed and is no longer providing protection (Correct answer)
- The GFCI is wired in reverse polarity
- The GFCI requires a 20-amp circuit to function properly
Correct answer: The GFCI device has failed and is no longer providing protection
If pressing the test button on a GFCI does not cause the reset button to pop out and interrupt power, the device has failed and must be replaced.
InterNACHI Electrical Systems and Safety 5
What is the required arc-fault circuit interrupter (AFCI) protection for bedroom circuits in homes built to current NEC standards?