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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).

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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 (422-18)

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 as chandeliers.

Pull-Chain Switches (210-70)

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 load.

Bonding Gas Pipes (250-104)

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 gas pipe. 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 (550-23)

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 foundation.

Swimming Pools

As usual 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 (210-12)

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).

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Figure 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.