Exhaust Fans in Showers (410-4)
The ’96 code made it illegal to hang fixtures such as
track lights or paddle fans in a 3x8-foot zone above a bathtub.
However, a poor choice of words inadvertently made it illegal
to install an exhaust fan over the tub or shower, which is
where most of my customers want it located. Luckily, most
inspectors were not enforcing this rule. New wording clarifies
the intent that an exhaust fan can be installed above a bathtub
but a paddle fan or other suspended fixture cannot (Figure
3. An exhaust fan can be installed in a 3x8-foot zone
above a bathtub or shower, but a paddle fan cannot.
Paddle Fan Support
Suspended ceiling fans weighing up to 70
pounds can now be hung directly from an outlet box without any
other independent support, as long as the box is listed for the
purpose. Previously, fans that weighed more than 35 pounds
required independent support.
Section 410-16 extends this to other types of fixtures such
Light fixtures with pull-chain switches
are now permitted to be installed in storage areas such as
attics, cellars, and utility rooms. The pull chain is required
to be near the entrance. In the past, a wall switch was
required for these locations.
Upgraded Service (230-79)
A 100-amp service is now the smallest service that can be
installed for a single family home. In the past a small house
could have a 60-amp service.
Sizing Service Conductors for
Multifamily Dwellings (230-90)
Under past codes,
sizing service conductors for multifamily dwellings was
confusing. Changes in ’99 make it clear that the service
conductors do not have to be sized based on the total number of
the individual disconnects, but rather on the total demand
Bonding Gas Pipes
Though it has long been required, the
bonding of all aboveground gas pipes to the service equipment
is now clearly spelled out. Even so, this may continue to be
one of the least enforced rules in the book. Some inspectors
tell me they still will not enforce this controversial law even
though it is now clearly required.
Many electricians and inspectors feel that bonding the gas
pipe will create a hazard. I disagree. The gas pipe is already
grounded by contact with the earth or by contact with grounded
electrical equipment. The problem is that neither of these
connections guarantees a good ground.
A poor ground is much more dangerous than a good ground
because, in a ground fault situation, extreme heat can build up
without tripping the circuit breaker. Bonding the gas pipe to
the service equipment creates a very good ground path back to
the electrical equipment, which will trip the circuit breaker
if a ground fault occurs before any heat can build up in the
Some questions come up about what type of clamp to use. The
clamps must be listed for connection to steel pipe and copper
or aluminum wire.
Central Vac Rules (422-15)
A separate circuit is no longer required for a central vacuum
system as long as the circuit complies with 210-23(a),
mentioned above under "Bathroom Circuits," which says that the
rating of the fixed equipment — the central vac, in this
case — cannot exceed 50% of the circuit rating. So, on a
15-amp circuit with other receptacles, the central vac could be
rated 7.5 amps, or 10 amps in a 20-amp circuit. Also, the
central vac must not exceed 80% of the rated load of a
dedicated circuit (12 amps on a 15-amp individual branch
circuit, 16 amps on a 20-amp).
Mobile Home Service
The service to a manufactured home
(mobile home) is permitted to be mounted directly on the
manufactured home only if the home is secured to a permanent
there are many changes to the rules for wiring swimming pools.
My advice is to consult with the electrical inspector when
wiring a pool. The rules are often misinterpreted and many
localities have their own rules for swimming pools.
Arc Fault Protection
Probably the most important change in
’99 won’t take affect until 2002, when all 15-amp
and 20-amp circuits feeding bedroom receptacles will be
required to be protected against arc-faults using an AFCI, or
arc fault circuit interrupter (Figure 4).
4. Beginning in 2002, AFCIs — arc
fault circuit interrupters — will be required
for bedroom receptacle circuits.
An arc fault can be caused by loose wiring connections or
old, corroded contacts in a switch or appliance. An AFCI is
designed to detect the difference between arcs caused by faulty
equipment and the kind of arcs that occur, say, in the motor of
a vacuum cleaner as a natural part of its operation.
Arc fault protection should cut down on the number of house
fires. The technology involved is so new that the NEC has
allowed a three-year delay on the rule to allow manufacturers
to further develop it and work the bugs out.