120-Question Practice Exam with Answers & Rationales
1. A GFCI outlet is required by code in which of the following locations in a
residential unit?
A. Bedrooms
B. Bathrooms and kitchens
C. Hallways
D. Living rooms
Correct Answer: B
Rationale: GFCI (Ground Fault Circuit Interrupter) protection is required in areas where
water and electricity are likely to come into contact, such as bathrooms, kitchens,
garages, and outdoor outlets, to prevent electric shock.
2. What is the standard voltage supplied to a typical residential outlet in the
United States?
A. 110-120 volts
B. 208 volts
C. 240 volts
D. 480 volts
Correct Answer: A
Rationale: Standard residential outlets in the U.S. supply approximately 110-120 volts,
while larger appliances like electric dryers and ranges typically use 240 volts.
3. Before performing any electrical repair, a maintenance technician should first:
A. Turn off the water supply
B. Notify the resident by mail only
C. De-energize the circuit at the breaker panel and verify with a voltage tester
D. Wear rubber-soled shoes only
Correct Answer: C
Rationale: Lockout/tagout procedures require the technician to de-energize the circuit at
the source and confirm with a voltage tester before touching any wiring, which is the
single most important safety step in electrical work.
,4. A circuit breaker that trips repeatedly after being reset most likely indicates:
A. A dead battery
B. An overloaded or shorted circuit
C. Low water pressure
D. A clogged air filter
Correct Answer: B
Rationale: Repeated tripping is a protective response by the breaker to an overloaded
circuit, a short circuit, or a ground fault, and the underlying cause must be found before
the breaker is reset again.
5. What tool is used to check whether a wire is carrying live current?
A. Voltage tester
B. Pipe wrench
C. Torque wrench
D. Refractometer
Correct Answer: A
Rationale: A voltage tester (or multimeter) is designed specifically to detect the
presence of electrical current, which confirms whether a wire is safe to handle.
6. In residential wiring, the black wire typically represents:
A. Ground
B. Neutral
C. Hot (energized)
D. Not used in the U.S.
Correct Answer: C
Rationale: By standard color convention, black wires (along with red) are hot/energized
conductors, white is neutral, and green or bare copper is ground.
,7. A flickering light in a unit that is not caused by the bulb itself is most likely due
to:
A. A loose wire connection
B. Low humidity
C. A dirty air filter
D. Old paint on the fixture
Correct Answer: A
Rationale: Flickering lights, when the bulb itself is not defective, are commonly caused
by a loose electrical connection at the switch, fixture, or panel, which should be
inspected and tightened.
8. What is the purpose of a circuit breaker panel directory (labeling)?
A. To decorate the panel
B. To identify which breaker controls which circuit or area
C. To track energy costs
D. To show the manufacturer's warranty
Correct Answer: B
Rationale: An accurate panel directory allows technicians to quickly identify and
de-energize the correct circuit, which is essential for both safety and efficiency.
9. An extension cord that feels warm to the touch during use may indicate:
A. Normal operation
B. The cord is overloaded and should not be used
C. The cord is too long
D. The outlet is grounded properly
Correct Answer: B
Rationale: A warm or hot extension cord signals that it is carrying more current than it is
rated for, creating a fire hazard; it should be replaced with a properly rated cord.
, 10. Which wire color is used for the ground connection in standard U.S.
residential wiring?
A. Red
B. White
C. Green or bare copper
D. Blue
Correct Answer: C
Rationale: Green insulated wire or bare copper wire is the standard designation for the
grounding conductor, which provides a safe path for fault current.
11. What should a maintenance technician do if they discover exposed or frayed
wiring in a unit?
A. Cover it with tape and move on
B. Repair the wiring immediately without turning off power
C. De-energize the circuit and repair or replace the wiring, or call a licensed
electrician if needed
D. Ignore it unless the resident complains
Correct Answer: C
Rationale: Exposed or frayed wiring is a serious shock and fire hazard. The circuit must
be de-energized before repair, and work beyond the technician's scope or license
should be referred to a licensed electrician.
12. A 3-prong plug that has been converted to fit a 2-prong outlet using an adapter
without a ground wire connection results in:
A. Improved safety
B. Loss of the equipment ground path, increasing shock risk
C. No change in performance
D. Automatic GFCI protection
Correct Answer: B
Rationale: Removing or bypassing the ground prong eliminates the safety path for fault
current, increasing the risk of electric shock if the appliance develops a fault.