Probably the most important change in the 2008 National Electrical Code®
(NEC®)is that Arc-Fault Circuit Interruption (AFCI) Protection is now required
for all 120-volt, single phase, 15- and 20 ampere branch circuits installed in
most areas of your home. The requirements which applied only to bedrooms in 2005
have been extended to every habitable area of the house in 2008.
210.12(B) Arc-Fault Circuit-Interrupter Protection (AFCI). Dwelling Units.
Arc-fault circuit interrupter protection is required in family rooms, dining
rooms, living rooms, parlors, libraries, dens, bedrooms, sun rooms, recreation
rooms, closets, hallways or similar rooms or areas.
AFCIs will not be required in bathrooms, kitchens, laundry rooms, unfinished
basements, garages, attics or outdoors.
More than 20,000,000 arc-fault circuit interrupter devices have been
installed to protect branch circuits in residential bedrooms since they were
first required in 2005. The electrical loads in the other areas of a house where
AFCIs are now required are similar to the electrical loads in a bedroom.
Bathroom, kitchen, garage and outdoor receptacle outlets supply different types
of electrical loads. In 2008, AFCI protection is not required in areas of a home
where electrical loads may have different characteristics than bedroom loads.
AFCI protection is only required in those areas of a dwelling with the types of
loads that have a proven track record of being compatible with AFCI
In locations where arc-fault protection is required in dwelling units, the
entire branch circuit must be protected. That means all the branch circuit
wiring from the panelboard to the last outlet on the circuit must be protected,
because any of that wiring is subject to arcing faults.
Exception No. 1 permits a combination type AFCI device (receptacle) to be
installed as the first outlet in the branch circuit, which provides protection
for the remaining portion of the branch circuit. This leaves the homerun wiring
between the panelboard and the first outlet without AFCI protection. If
Exception No. 1 is used, and AFCI protection starts at the first outlet, the
homerun wiring must be installed in metal conduit or cable, Type RMC, IMC, EMT
or Type AC cable. Type MC cable is not permitted because the walls of Type MC
cable are thinner than the walls of Type AC cable. All these wiring methods meet
the requirements for equipment grounding conductors in 250.118. Metal boxes are
The 2005 NEC® permitted the AFCI device to be located outside the panelboard,
but it had to be installed within 6 ft. of the branch circuit overcurrent
device. The 6 ft. limit from the panelboard to the first AFCI device has been
eliminated in 2008, and a combination AFCI device can be installed as the first
outlet on the branch circuit at any distance from the panelboard as long as the
homerun is installed in one of the metallic wiring methods described in the