210.12 Arc-Fault Circuit-Interrupter Protection. Arcfault
circuit-interrupter protection shall be provided as required
in 210.12(A) (B), and (C). The arc-fault circuit interrupter
shall be installed in a readily accessible location.
(A) Dwelling Units. All 120-volt, single-phase, 15- and
20-ampere branch circuits supplying outlets or devices installed
in dwelling unit kitchens, family rooms, dining
rooms, living rooms, parlors, libraries, dens, bedrooms,
sunrooms, recreation rooms, closets, hallways, laundry areas,
or similar rooms or areas shall be protected by any of
the means described in 210.12(A)(1) through (6):
(1) A listed combination-type arc-fault circuit interrupter,
installed to provide protection of the entire branch circuit
(2) A listed branch/feeder-type AFCI installed at the origin
of the branch-circuit in combination with a listed outlet
branch-circuit type arc-fault circuit interrupter installed
at the first outlet box on the branch circuit. The first
outlet box in the branch circuit shall be marked to indicate
that it is the first outlet of the circuit.
(3) A listed supplemental arc protection circuit breaker installed
at the origin of the branch circuit in combination
with a listed outlet branch-circuit type arc-fault circuit
interrupter installed at the first outlet box on the branch
circuit where all of the following conditions are met:
a. The branch-circuit wiring shall be continuous from
the branch-circuit overcurrent device to the outlet
branch-circuit arc-fault circuit interrupter.
b. The maximum length of the branch-circuit wiring
from the branch-circuit overcurrent device to the
first outlet shall not exceed 15.2 m (50 ft) for a
14 AWG conductor or 21.3 m (70 ft) for a 12 AWG
conductor.
c. The first outlet box in the branch circuit shall be
marked to indicate that it is the first outlet of the
circuit.
(4) A listed outlet branch-circuit type arc-fault circuit interrupter
installed at the first outlet on the branch circuit
in combination with a listed branch-circuit overcurrent
protective device where all of the following
conditions are met:
a. The branch-circuit wiring shall be continuous from
the branch-circuit overcurrent device to the outlet
branch-circuit arc-fault circuit interrupter.
b. The maximum length of the branch-circuit wiring
from the branch-circuit overcurrent device to the
first outlet shall not exceed 15.2 m (50 ft) for a
14 AWG conductor or 21.3 m (70 ft) for a 12 AWG
conductor.
c. The first outlet box in the branch circuit shall be
marked to indicate that it is the first outlet of the
circuit.
d. The combination of the branch-circuit overcurrent
device and outlet branch-circuit AFCI shall be identified
as meeting the requirements for a system
combination–type AFCI and shall be listed as such.
(5) If RMC, IMC, EMT, Type MC, or steel-armored Type
AC cables meeting the requirements of 250.118, metal
wireways, metal auxiliary gutters, and metal outlet and
junction boxes are installed for the portion of the
branch circuit between the branch-circuit overcurrent
device and the first outlet, it shall be permitted to install
a listed outlet branch-circuit type AFCI at the first outlet
to provide protection for the remaining portion of
the branch circuit.
(6) Where a listed metal or nonmetallic conduit or tubing
or Type MC cable is encased in not less than 50 mm
(2 in.) of concrete for the portion of the branch circuit
between the branch-circuit overcurrent device and the
first outlet, it shall be permitted to install a listed outlet
branch-circuit type AFCI at the first outlet to provide
protection for the remaining portion of the branch
circuit.
Exception: Where an individual branch circuit to a fire
alarm system installed in accordance with 760.41(B) or
760.121(B) is installed in RMC, IMC, EMT, or steelsheathed
cable, Type AC or Type MC, meeting the requirements
of 250.118, with metal outlet and junction boxes,
AFCI protection shall be permitted to be omitted.