ICC E1 Residential Electrical Inspector Practice Test

Sample Questions and Answers

Question 1. A dwelling-unit kitchen receptacle is installed to serve countertop space. Which protection is generally required for this receptacle?

A. Arc-fault circuit-interrupter protection only
B. Ground-fault circuit-interrupter protection
C. Surge protection only
D. No additional protection

Correct Answer. B.

Explanation: Receptacles serving dwelling-unit kitchen countertop areas are generally required to have ground-fault circuit-interrupter protection. GFCI protection is intended to reduce the risk of electric shock by interrupting the circuit when a difference in current indicates that some current is flowing through an unintended path. AFCI protection addresses hazards associated with electrical arcing and does not replace GFCI protection where GFCI is required. Surge protection serves a different purpose and does not satisfy the GFCI requirement. During an inspection, the inspector should consider the receptacle’s location, intended use, circuit arrangement, and any applicable exceptions before determining whether the installation complies.

Question 2. A 20-ampere branch circuit in a dwelling supplies general-purpose receptacles. Which copper conductor size is generally used for this circuit?

A. 14 AWG
B. 16 AWG
C. 12 AWG
D. 18 AWG

Correct Answer. C.

Explanation: A typical 20-ampere branch circuit requires conductors with an ampacity appropriate for the circuit rating. For standard copper conductors, 12 AWG is generally used for a 20-ampere branch circuit. Fourteen AWG copper is generally associated with 15-ampere circuits and therefore would not normally be appropriate for a standard 20-ampere circuit. Sixteen and eighteen AWG conductors are also unsuitable for this application. The inspector should nevertheless evaluate the complete installation rather than relying only on conductor size. Ambient temperature, adjustment factors, conductor insulation ratings, terminal limitations, and other applicable requirements can affect allowable ampacity.

Question 3. An electrical box contains insulated conductors, equipment grounding conductors, an internal cable clamp, and a wiring device. What should the inspector verify?

A. Only that the cover can be installed
B. That the box has adequate volume under the applicable box-fill requirements
C. That all conductors have different insulation colors
D. That equipment grounding conductors are removed from the box

Correct Answer. B.

Explanation: An electrical box must provide sufficient volume for the conductors and components installed inside it. The box-fill calculation considers conductor size and quantity as well as applicable allowances for equipment grounding conductors, internal cable clamps, devices, and other components. The fact that a cover can physically be installed does not establish compliance. Conductor color identification is a separate requirement and does not determine box volume. Equipment grounding conductors must not simply be removed to reduce the calculated fill. The inspector should identify all conductors and components that count under the applicable requirements, calculate the required volume, and compare it with the box’s listed capacity.

Question 4. A nonmetallic-sheathed cable is installed through a wood framing member too close to the face of the framing for the required clearance from nails or screws. What should the inspector look for?

A. An approved protective device against physical damage
B. A larger circuit breaker
C. An additional grounding conductor
D. Additional insulation at the service panel

Correct Answer. A.

Explanation: Electrical cables installed near the face of framing members must be protected when their location creates a risk of penetration by nails, screws, or similar fasteners. When the required clearance cannot be maintained, an approved means of protection, such as a suitable nail plate where applicable, may be necessary. A larger circuit breaker does not protect the cable against mechanical penetration. An additional grounding conductor addresses a different electrical function and does not provide physical protection. Likewise, adding insulation at the panel does nothing to protect cable located at the framing member. The inspector should evaluate the cable’s location and the applicable physical-protection requirements.

Question 5. A residential swimming pool installation contains accessible metal components that could be contacted by a person in the pool area. What is the primary purpose of the required bonding system?

A. Increase the operating voltage of pool equipment
B. Minimize differences in electrical potential between conductive parts
C. Replace required ground-fault protection
D. Permit ordinary extension cords to supply pool equipment

Correct Answer. B.

Explanation: Bonding around a swimming pool is intended to minimize differences in electrical potential between accessible conductive parts that could be contacted simultaneously. Connecting required conductive components through an equipotential bonding system helps reduce the possibility of dangerous voltage differences developing between those components. Bonding does not increase the normal operating voltage of equipment and does not replace GFCI protection, which serves a separate protective function. It also does not make ordinary extension-cord use acceptable around pool installations. When inspecting pool electrical work, the inspector should evaluate bonding together with grounding, GFCI protection, equipment location, wiring methods, and the other requirements applicable to the particular installation.