IEC FINAL PAPER 2026 QUESTIONS WITH
ANSWERS GRADED A+
◉ A cable, raceway, or box, installed in exposed or concealed locations
under metal-corrugated sheet roof decking, shall be installed and
supported so there is not less than ___ measured from the lowest surface
of the roof decking to the top of the cable, raceway, or box. Answer: 11/2
inch
◉ Underground service conductors that are not encased in concrete and
that are buried ___ or more below grade shall have their location
identified by a warning ribbon that is placed at least 12 inches above the
underground installation. Answer: 18 inches
◉ When installed in raceways, conductors ___ AWG and larger shall be
stranded. Answer: 8
◉ When eight (8) current-carrying conductors are in one conduit, the
ampacity of each conductor is adjusted to ___ percent. Answer: 70
◉ What is the circular mil area of a 3/0 AWG conductor? Answer:
167,800
,◉ Fittings and connectors shall be used only with the specific wiring
methods for which they are ___. Answer: II & III only
◉ Where conductors carrying alternating current are installed in metal
enclosures or metal raceways, they shall be arranged so as to avoid
heating the surrounding metal by ___. Answer: induction
◉ Which of the following conductor arrangements is permitted by the
NEC®? Answer: a or b only
◉ 207.8 Answer: a
◉ 207.10 Answer: I, II & III
◉ 207.11 Answer: Where the upper wiring method is EMT and contains
circuit conductors to a heating unit and the lower wiring method is Class
2 thermostat cable for the heating unit.
◉ 207.12 Answer: II & III only
◉ In vertical conduit runs, such as up through a high-rise building,
conductors made of aluminum have support requirements that are ___
than for copper conductors. Answer: farther apart
,◉ Where a conduit passes through an exterior wall and enters a panel
mounted on the interior, seals or plugs ___ required. Answer: are
◉ To avoid heating problems due to induction, the Code generally
prohibits installing a single conductor of an alternating-current (ac)
system in a metallic raceway. Which of the following single conductors
of an ac system is permitted to be installed by itself in a metallic
raceway? Answer: grounding electrode conductor
◉ A metal box or terminal fitting having separately bushed holes for
each conductor shall be used whenever change is made from conduit to
Answer: knob and tube wiring
◉ In areas where the walls are frequently washed, conduit should be
mounted with a ___ inch air space between the wall and the conduit.
Answer: 1/4
◉ All metal raceways, cable armor, fittings, cabinets, and other metal
enclosures for conductors must be ___ joined together to form a
continuous electrical conductor. Answer: metallically
◉ Conductors in raceways must be ___ between outlet devices, and
there shall be no splices or taps within the raceways. Answer: continuous
, ◉ When connections are made in the white wire to receptacles in a
multiwire branch circuit, they are required to be Answer: made with a
pigtail to the silver terminal
◉ A service lateral is to be installed as direct-buried cable in the bottom
of a trench that is 42 inches below finish grade. The trench is to be filled
with dirt only. A warning ribbon is required to be installed in the trench
at a maximum depth of ___ inches below finish grade. Answer: 30
◉ 207.14 The wiring method is PVC. The minimum distance permitted
beneath the sidewalk at Point A (from the bottom of the 4″ thick
sidewalk to the top of the conduit) is ___ inches. Answer: 0
◉ Schedule 40 PVC is the wiring method installed beneath the grassy
area shown above in Figure 207.15. A 120-volt circuit is fed from a 15-
Amp GFCI breaker in the restaurant. The minimum dimension permitted
for Y is ___ inches. Answer: 18
◉ Refer to Figure 207.19, shown above, where luminaires have been
installed along a driveway to a single-family ranch home. Type UF cable
is the wiring method installed between the luminaires and along the side
of the drive. The minimum dimension permitted for Y along the side of
the driveway is ___ inches. Answer: 24
◉ Refer to Figure 207.17, shown above. The NEC® cover requirements
for the underground conduit in Area B are taken from the row in Table
ANSWERS GRADED A+
◉ A cable, raceway, or box, installed in exposed or concealed locations
under metal-corrugated sheet roof decking, shall be installed and
supported so there is not less than ___ measured from the lowest surface
of the roof decking to the top of the cable, raceway, or box. Answer: 11/2
inch
◉ Underground service conductors that are not encased in concrete and
that are buried ___ or more below grade shall have their location
identified by a warning ribbon that is placed at least 12 inches above the
underground installation. Answer: 18 inches
◉ When installed in raceways, conductors ___ AWG and larger shall be
stranded. Answer: 8
◉ When eight (8) current-carrying conductors are in one conduit, the
ampacity of each conductor is adjusted to ___ percent. Answer: 70
◉ What is the circular mil area of a 3/0 AWG conductor? Answer:
167,800
,◉ Fittings and connectors shall be used only with the specific wiring
methods for which they are ___. Answer: II & III only
◉ Where conductors carrying alternating current are installed in metal
enclosures or metal raceways, they shall be arranged so as to avoid
heating the surrounding metal by ___. Answer: induction
◉ Which of the following conductor arrangements is permitted by the
NEC®? Answer: a or b only
◉ 207.8 Answer: a
◉ 207.10 Answer: I, II & III
◉ 207.11 Answer: Where the upper wiring method is EMT and contains
circuit conductors to a heating unit and the lower wiring method is Class
2 thermostat cable for the heating unit.
◉ 207.12 Answer: II & III only
◉ In vertical conduit runs, such as up through a high-rise building,
conductors made of aluminum have support requirements that are ___
than for copper conductors. Answer: farther apart
,◉ Where a conduit passes through an exterior wall and enters a panel
mounted on the interior, seals or plugs ___ required. Answer: are
◉ To avoid heating problems due to induction, the Code generally
prohibits installing a single conductor of an alternating-current (ac)
system in a metallic raceway. Which of the following single conductors
of an ac system is permitted to be installed by itself in a metallic
raceway? Answer: grounding electrode conductor
◉ A metal box or terminal fitting having separately bushed holes for
each conductor shall be used whenever change is made from conduit to
Answer: knob and tube wiring
◉ In areas where the walls are frequently washed, conduit should be
mounted with a ___ inch air space between the wall and the conduit.
Answer: 1/4
◉ All metal raceways, cable armor, fittings, cabinets, and other metal
enclosures for conductors must be ___ joined together to form a
continuous electrical conductor. Answer: metallically
◉ Conductors in raceways must be ___ between outlet devices, and
there shall be no splices or taps within the raceways. Answer: continuous
, ◉ When connections are made in the white wire to receptacles in a
multiwire branch circuit, they are required to be Answer: made with a
pigtail to the silver terminal
◉ A service lateral is to be installed as direct-buried cable in the bottom
of a trench that is 42 inches below finish grade. The trench is to be filled
with dirt only. A warning ribbon is required to be installed in the trench
at a maximum depth of ___ inches below finish grade. Answer: 30
◉ 207.14 The wiring method is PVC. The minimum distance permitted
beneath the sidewalk at Point A (from the bottom of the 4″ thick
sidewalk to the top of the conduit) is ___ inches. Answer: 0
◉ Schedule 40 PVC is the wiring method installed beneath the grassy
area shown above in Figure 207.15. A 120-volt circuit is fed from a 15-
Amp GFCI breaker in the restaurant. The minimum dimension permitted
for Y is ___ inches. Answer: 18
◉ Refer to Figure 207.19, shown above, where luminaires have been
installed along a driveway to a single-family ranch home. Type UF cable
is the wiring method installed between the luminaires and along the side
of the drive. The minimum dimension permitted for Y along the side of
the driveway is ___ inches. Answer: 24
◉ Refer to Figure 207.17, shown above. The NEC® cover requirements
for the underground conduit in Area B are taken from the row in Table
