LADWP ELECTRICAL CRAFT HELPER EXAM
2026 | PRACTICE QUESTIONS & VERIFIED
ANSWERS | DETAILED RATIONALES
LADWP ELECTRICAL CRAFT HELPER EXAM 2026 | PRACTICE QUESTIONS &
VERIFIED ANSWERS | DETAILED RATIONALES
DOCUMENT OVERVIEW
• This comprehensive practice exam contains 200 verified questions designed to
prepare candidates for the LADWP Electrical Craft Helper certification, covering all
critical domains including electrical safety, code compliance, circuit theory, wiring
practices, and hands-on troubleshooting.
• Use this material by studying 15-20 questions daily, reviewing the detailed
rationales for both correct and incorrect answers, and focusing on areas where you
score below 85% before attempting the full 200-question test.
QUESTIONS 1-50: ELECTRICAL SAFETY & HAZARDS
1. What is the primary reason for using a Ground Fault Circuit Interrupter
(GFCI) in wet locations?
A) To increase the voltage capacity of the circuit
B) To reduce electrical noise in the wiring
C) To protect personnel from electric shock by detecting ground faults
D) To improve the power factor of the installation
E) To reduce the overall cost of electrical installation
CORRECT ANSWER: C) To protect personnel from electric shock by detecting
ground faults
RATIONALE: GFCIs are designed to detect imbalances in current flow between the
hot and neutral conductors, which indicates a ground fault condition. When a
ground fault is detected (even a very small one), the GFCI trips and de-energizes the
,circuit in milliseconds, protecting workers from potentially fatal electric shock. This
is particularly critical in wet locations like bathrooms, kitchens, and outdoor areas
where the risk of contact with water and grounded surfaces is high.
2. According to OSHA standards, what is the maximum voltage that is
considered "low voltage" in electrical work?
A) 24 volts
B) 50 volts
C) 120 volts
D) 240 volts
E) 600 volts
CORRECT ANSWER: B) 50 volts
RATIONALE: OSHA defines low voltage as any voltage not exceeding 50 volts AC (or
120 volts DC). Voltages above this threshold require special precautions and
protective equipment. This distinction is important because circuits operating at or
below 50 volts AC pose significantly reduced shock hazards and have different
safety requirements compared to standard household voltage (120/240V) or
industrial three-phase systems.
3. What must you do before working on any electrical circuit that has been de-
energized?
A) Assume it is safe and begin work immediately
B) Test the circuit with a voltmeter to verify de-energization
C) Wait 5 minutes for any residual charge to dissipate
D) Ask a coworker if they think it is safe
E) Apply a ground clamp before testing
,CORRECT ANSWER: B) Test the circuit with a voltmeter to verify de-
energization
RATIONALE: The "test before work" rule is fundamental in electrical safety. Even
after a circuit has been switched off and locked out, residual voltage or unintended
backfeeding through parallel circuits can still be present. Using a voltmeter to verify
that no voltage is present before beginning work is the only reliable method to
ensure worker safety. This step must be performed every single time, without
exception, as a matter of professional practice and regulatory compliance.
4. Which type of arc flash hazard has the highest incident energy?
A) Bolted fault arc
B) Series arc
C) Parallel arc
D) Three-phase arc fault
E) Direct contact arc
CORRECT ANSWER: A) Bolted fault arc
RATIONALE: A bolted fault arc, also called a three-phase bolted fault, occurs when
there is a direct short circuit between conductors and produces the highest incident
energy release. This is the condition used to calculate maximum arc flash hazard in
electrical equipment rooms and switchgear areas. The bolted fault scenario
represents the worst-case condition and is therefore used as the baseline for
determining Personal Protective Equipment (PPE) requirements.
5. What is the proper procedure when an electrical fire occurs?
A) Pour water directly on the flames
B) Use a Class C fire extinguisher and de-energize the equipment if possible
C) Use a Class A fire extinguisher
, D) Attempt to smother the fire with blankets
E) Remove the electrical panel cover to access the wiring
CORRECT ANSWER: B) Use a Class C fire extinguisher and de-energize the
equipment if possible
RATIONALE: Electrical fires require a Class C extinguisher because water and other
conductive materials can conduct electricity and cause electrocution. Class C
extinguishers contain non-conductive extinguishing agents (typically dry powder or
inert gas). The best practice is to de-energize the source of the electrical fire first (if
safely possible), then apply the appropriate extinguisher. Only after the equipment
is de-energized can you transition to other extinguisher types if necessary.
6. Under what circumstances is it acceptable to use a single-strand wire
instead of a properly stranded conductor?
A) When installing temporary wiring
B) When the circuit is low voltage
C) Never—proper stranded wire must always be used
D) When the distance is less than 10 feet
E) When the wire is protected by conduit
CORRECT ANSWER: C) Never—proper stranded wire must always be used
RATIONALE: The NEC and all electrical codes mandate the use of proper multi-
strand conductors for all permanent installations. Single-strand wire (solid wire)
becomes brittle under repeated flexing, is more difficult to terminate properly, and
presents safety hazards. While solid conductors may be permitted in specific
applications like conduit work, improvising with single-strand wire in place of
proper stranded conductors is a code violation and safety violation. Professional
electrical work always requires proper materials.
2026 | PRACTICE QUESTIONS & VERIFIED
ANSWERS | DETAILED RATIONALES
LADWP ELECTRICAL CRAFT HELPER EXAM 2026 | PRACTICE QUESTIONS &
VERIFIED ANSWERS | DETAILED RATIONALES
DOCUMENT OVERVIEW
• This comprehensive practice exam contains 200 verified questions designed to
prepare candidates for the LADWP Electrical Craft Helper certification, covering all
critical domains including electrical safety, code compliance, circuit theory, wiring
practices, and hands-on troubleshooting.
• Use this material by studying 15-20 questions daily, reviewing the detailed
rationales for both correct and incorrect answers, and focusing on areas where you
score below 85% before attempting the full 200-question test.
QUESTIONS 1-50: ELECTRICAL SAFETY & HAZARDS
1. What is the primary reason for using a Ground Fault Circuit Interrupter
(GFCI) in wet locations?
A) To increase the voltage capacity of the circuit
B) To reduce electrical noise in the wiring
C) To protect personnel from electric shock by detecting ground faults
D) To improve the power factor of the installation
E) To reduce the overall cost of electrical installation
CORRECT ANSWER: C) To protect personnel from electric shock by detecting
ground faults
RATIONALE: GFCIs are designed to detect imbalances in current flow between the
hot and neutral conductors, which indicates a ground fault condition. When a
ground fault is detected (even a very small one), the GFCI trips and de-energizes the
,circuit in milliseconds, protecting workers from potentially fatal electric shock. This
is particularly critical in wet locations like bathrooms, kitchens, and outdoor areas
where the risk of contact with water and grounded surfaces is high.
2. According to OSHA standards, what is the maximum voltage that is
considered "low voltage" in electrical work?
A) 24 volts
B) 50 volts
C) 120 volts
D) 240 volts
E) 600 volts
CORRECT ANSWER: B) 50 volts
RATIONALE: OSHA defines low voltage as any voltage not exceeding 50 volts AC (or
120 volts DC). Voltages above this threshold require special precautions and
protective equipment. This distinction is important because circuits operating at or
below 50 volts AC pose significantly reduced shock hazards and have different
safety requirements compared to standard household voltage (120/240V) or
industrial three-phase systems.
3. What must you do before working on any electrical circuit that has been de-
energized?
A) Assume it is safe and begin work immediately
B) Test the circuit with a voltmeter to verify de-energization
C) Wait 5 minutes for any residual charge to dissipate
D) Ask a coworker if they think it is safe
E) Apply a ground clamp before testing
,CORRECT ANSWER: B) Test the circuit with a voltmeter to verify de-
energization
RATIONALE: The "test before work" rule is fundamental in electrical safety. Even
after a circuit has been switched off and locked out, residual voltage or unintended
backfeeding through parallel circuits can still be present. Using a voltmeter to verify
that no voltage is present before beginning work is the only reliable method to
ensure worker safety. This step must be performed every single time, without
exception, as a matter of professional practice and regulatory compliance.
4. Which type of arc flash hazard has the highest incident energy?
A) Bolted fault arc
B) Series arc
C) Parallel arc
D) Three-phase arc fault
E) Direct contact arc
CORRECT ANSWER: A) Bolted fault arc
RATIONALE: A bolted fault arc, also called a three-phase bolted fault, occurs when
there is a direct short circuit between conductors and produces the highest incident
energy release. This is the condition used to calculate maximum arc flash hazard in
electrical equipment rooms and switchgear areas. The bolted fault scenario
represents the worst-case condition and is therefore used as the baseline for
determining Personal Protective Equipment (PPE) requirements.
5. What is the proper procedure when an electrical fire occurs?
A) Pour water directly on the flames
B) Use a Class C fire extinguisher and de-energize the equipment if possible
C) Use a Class A fire extinguisher
, D) Attempt to smother the fire with blankets
E) Remove the electrical panel cover to access the wiring
CORRECT ANSWER: B) Use a Class C fire extinguisher and de-energize the
equipment if possible
RATIONALE: Electrical fires require a Class C extinguisher because water and other
conductive materials can conduct electricity and cause electrocution. Class C
extinguishers contain non-conductive extinguishing agents (typically dry powder or
inert gas). The best practice is to de-energize the source of the electrical fire first (if
safely possible), then apply the appropriate extinguisher. Only after the equipment
is de-energized can you transition to other extinguisher types if necessary.
6. Under what circumstances is it acceptable to use a single-strand wire
instead of a properly stranded conductor?
A) When installing temporary wiring
B) When the circuit is low voltage
C) Never—proper stranded wire must always be used
D) When the distance is less than 10 feet
E) When the wire is protected by conduit
CORRECT ANSWER: C) Never—proper stranded wire must always be used
RATIONALE: The NEC and all electrical codes mandate the use of proper multi-
strand conductors for all permanent installations. Single-strand wire (solid wire)
becomes brittle under repeated flexing, is more difficult to terminate properly, and
presents safety hazards. While solid conductors may be permitted in specific
applications like conduit work, improvising with single-strand wire in place of
proper stranded conductors is a code violation and safety violation. Professional
electrical work always requires proper materials.
