IAEI Residential Electrical Inspector
Examination Questions and Correct Answers
(Verified Answers) Plus Rationale 2026 Q&A |
Instant Download PDF
SECTION 1: GENERAL REQUIREMENTS AND DEFINITIONS
1. What is the minimum size copper grounding electrode conductor (AWG)
required for a residential service with 200-amp service?
a) 6 AWG
b) 4 AWG
c) 2 AWG
d) 1/0 AWG
Rationale: NEC Table 250.66 requires a 4 AWG copper grounding electrode
conductor for a 200-amp residential service based on the service entrance
conductor size.
2. According to the NEC, what is the definition of a "dwelling unit"?
a) Any building used for commercial purposes
b) A single unit providing complete independent living facilities for one or
more persons
c) A room in a hotel or motel
d) Any structure with sleeping quarters
Rationale: NEC Article 100 defines a dwelling unit as a single unit providing
complete independent living facilities for one or more persons, including
permanent provisions for living, sleeping, cooking, and sanitation.
3. What is the minimum height requirement for a residential electrical service
mast?
a) 8 feet
b) 10 feet
,c) 12 feet
d) 15 feet
Rationale: NEC 230.24(A) requires service conductors to have a minimum height
of 10 feet above finished grade for residential installations.
4. Which of the following is NOT considered a "readily accessible" location?
a) A switch mounted at eye level
b) A panel in a hallway
c) An attic requiring a ladder to access
d) A receptacle on a kitchen wall
Rationale: NEC Article 100 defines "readily accessible" as capable of being
reached quickly for operation, renewal, or inspection without requiring climbing
over obstacles or using portable ladders.
5. The minimum working space in front of an electrical panel is:
a) 24 inches
b) 30 inches
c) 36 inches
d) 42 inches
Rationale: NEC 110.26(A)(1) requires a working space of at least 36 inches in
front of electrical equipment operating at 600 volts or less.
6. What is the minimum width of the working space in front of electrical
equipment?
a) 24 inches
b) 30 inches
c) 36 inches
d) 48 inches
Rationale: NEC 110.26(A)(2) requires the working space width to be at least 30
inches or the width of the equipment, whichever is greater.
,7. When installing electrical equipment in a damp location, what is required?
a) Standard equipment only
b) Equipment suitable for damp locations
c) Weatherproof equipment only
d) No special requirements
Rationale: NEC 110.11 requires equipment installed in damp or wet locations to
be suitable for such conditions.
8. What is the maximum height for a disconnect switch in a residential
application?
a) 5 feet
b) 6 feet 7 inches
c) 7 feet
d) 8 feet
Rationale: NEC 404.8(A) requires switches to be installed so that the center of the
operating handle is not more than 6 feet 7 inches above the floor or working
platform.
9. The term "ground fault" is defined as:
a) A short circuit between two hot conductors
b) An unintentional electrically conductive connection between an
ungrounded conductor and earth
c) A connection between the neutral and ground
d) An overload condition
Rationale: NEC Article 100 defines a ground fault as an unintentional electrically
conductive connection between an ungrounded conductor and the earth or a
grounded metal object.
10. Which of the following is considered a "continuous load"?
a) Lighting that operates for 1 hour
b) A load where the maximum current is expected to continue for 3 hours or
more
, c) Any motor load
d) All residential loads
Rationale: NEC Article 100 defines a continuous load as a load where the
maximum current is expected to continue for 3 hours or more.
SECTION 2: SERVICES AND FEEDERS
11. What is the minimum service disconnect rating for a single-family
dwelling?
a) 60 amps
b) 100 amps
c) 150 amps
d) 200 amps
Rationale: NEC 230.79(C) requires the minimum service disconnect rating for a
single-family dwelling to be 100 amperes.
12. A residential service may have a maximum of how many disconnecting
means?
a) 2
b) 4
c) 6
d) 8
Rationale: NEC 230.71(A) permits a maximum of six disconnecting means for
each service, grouped in one location.
13. The service-entrance conductors must have a clearance of at least what
distance from the roof?
a) 12 inches
b) 24 inches
c) 36 inches
d) 48 inches
Rationale: NEC 230.24(A) requires service conductors to have a minimum
clearance of 36 inches from the roof surface.
Examination Questions and Correct Answers
(Verified Answers) Plus Rationale 2026 Q&A |
Instant Download PDF
SECTION 1: GENERAL REQUIREMENTS AND DEFINITIONS
1. What is the minimum size copper grounding electrode conductor (AWG)
required for a residential service with 200-amp service?
a) 6 AWG
b) 4 AWG
c) 2 AWG
d) 1/0 AWG
Rationale: NEC Table 250.66 requires a 4 AWG copper grounding electrode
conductor for a 200-amp residential service based on the service entrance
conductor size.
2. According to the NEC, what is the definition of a "dwelling unit"?
a) Any building used for commercial purposes
b) A single unit providing complete independent living facilities for one or
more persons
c) A room in a hotel or motel
d) Any structure with sleeping quarters
Rationale: NEC Article 100 defines a dwelling unit as a single unit providing
complete independent living facilities for one or more persons, including
permanent provisions for living, sleeping, cooking, and sanitation.
3. What is the minimum height requirement for a residential electrical service
mast?
a) 8 feet
b) 10 feet
,c) 12 feet
d) 15 feet
Rationale: NEC 230.24(A) requires service conductors to have a minimum height
of 10 feet above finished grade for residential installations.
4. Which of the following is NOT considered a "readily accessible" location?
a) A switch mounted at eye level
b) A panel in a hallway
c) An attic requiring a ladder to access
d) A receptacle on a kitchen wall
Rationale: NEC Article 100 defines "readily accessible" as capable of being
reached quickly for operation, renewal, or inspection without requiring climbing
over obstacles or using portable ladders.
5. The minimum working space in front of an electrical panel is:
a) 24 inches
b) 30 inches
c) 36 inches
d) 42 inches
Rationale: NEC 110.26(A)(1) requires a working space of at least 36 inches in
front of electrical equipment operating at 600 volts or less.
6. What is the minimum width of the working space in front of electrical
equipment?
a) 24 inches
b) 30 inches
c) 36 inches
d) 48 inches
Rationale: NEC 110.26(A)(2) requires the working space width to be at least 30
inches or the width of the equipment, whichever is greater.
,7. When installing electrical equipment in a damp location, what is required?
a) Standard equipment only
b) Equipment suitable for damp locations
c) Weatherproof equipment only
d) No special requirements
Rationale: NEC 110.11 requires equipment installed in damp or wet locations to
be suitable for such conditions.
8. What is the maximum height for a disconnect switch in a residential
application?
a) 5 feet
b) 6 feet 7 inches
c) 7 feet
d) 8 feet
Rationale: NEC 404.8(A) requires switches to be installed so that the center of the
operating handle is not more than 6 feet 7 inches above the floor or working
platform.
9. The term "ground fault" is defined as:
a) A short circuit between two hot conductors
b) An unintentional electrically conductive connection between an
ungrounded conductor and earth
c) A connection between the neutral and ground
d) An overload condition
Rationale: NEC Article 100 defines a ground fault as an unintentional electrically
conductive connection between an ungrounded conductor and the earth or a
grounded metal object.
10. Which of the following is considered a "continuous load"?
a) Lighting that operates for 1 hour
b) A load where the maximum current is expected to continue for 3 hours or
more
, c) Any motor load
d) All residential loads
Rationale: NEC Article 100 defines a continuous load as a load where the
maximum current is expected to continue for 3 hours or more.
SECTION 2: SERVICES AND FEEDERS
11. What is the minimum service disconnect rating for a single-family
dwelling?
a) 60 amps
b) 100 amps
c) 150 amps
d) 200 amps
Rationale: NEC 230.79(C) requires the minimum service disconnect rating for a
single-family dwelling to be 100 amperes.
12. A residential service may have a maximum of how many disconnecting
means?
a) 2
b) 4
c) 6
d) 8
Rationale: NEC 230.71(A) permits a maximum of six disconnecting means for
each service, grouped in one location.
13. The service-entrance conductors must have a clearance of at least what
distance from the roof?
a) 12 inches
b) 24 inches
c) 36 inches
d) 48 inches
Rationale: NEC 230.24(A) requires service conductors to have a minimum
clearance of 36 inches from the roof surface.
