Jim Dollard has an extensive background in codes and standards. Send questions about the National Electrical Code (NEC) to Jim at [email protected]. Answers are based on the 2023 NEC.

Panelboard in a stairway

Is it NEC-compliant to place a load center in the wall of a stairway? It seems like the working space in front of this equipment would be compromised by the stairs. 

Panelboards contain circuit breakers that are overcurrent devices. Section 240.24(F)  prohibits overcurrent protective devices from being installed/located over the steps of a stairway. As long as the required working space can be maintained, a panelboard could be installed on a stairway landing as it would not be located over the “steps of the stairway.”

Fire-resistant-rated walls and more

When applying the requirement in Section 300.21, there seems to be some debate on whether all wall penetrations need to be fire-stopped or just penetrations through fire-rated walls. The use of mandatory text and the words “substantially increased” seem to broad-brush this rule for all walls, etc. Are we reading into this too much?

This is an interesting question. The first sentence in Section 300.21 is not directed at fire-stopping, fire-resistant-rated walls, partitions, floors or ceilings. It is directed at “all electrical installations in hollow spaces, vertical shafts, and ventilation or air-­handling ducts.” The intent is to ensure the possible spread of fire or products of combustion will not be “substantially increased” due to oversized holes or penetrations. For example, we do not want an installer to make a 4-inch round hole for a ¾-inch EMT penetration, as such a large opening would “substantially increase” the spread of fire or products of combustion. This could mean the AHJ may request oversized holes in nonrated walls, partitions, floors or ceilings be patched with drywall compound, caulk or another approved product. The requirement’s second sentence mandates openings around electrical penetrations into or through fire-resistant-rated walls, partitions, floors or ceilings be fire-stopped.

Dial down the instantaneous?

As an inspector, I am always trying to learn. A contractor recently purchased a used switchboard that contained multiple circuit breakers rated 1,200A or more. I did not see a means of arc energy reduction for those devices. He told me that it was permitted to dial the instantaneous function on the circuit breaker all the way down to comply with 240.87. Is that permitted?

No, see 240.87(B), which includes all permitted methods to reduce the circuit breaker clearing time. List item 240.87(B)(5) permits an instantaneous trip setting only where it is set to operate at less than the available arcing current, and that must be documented. See 240.87(A). List item 240.87(B)(5) contains additional text that very clearly prohibits temporary adjustment of the instantaneous trip setting to achieve arc energy reduction.

Wireway and workspace clearance

Does a metal wireway require workspace clearance? We are seriously confused here. One inspector told us that a metal wireway is equipment and 110.26 applies, and others say no. Can you help?

The term “metal wireway” is defined in Article 100 as sheet metal troughs with hinged or removable covers for housing and protecting electrical wires and cable and in which conductors are laid in place after the raceway has been installed as a complete system. As defined, a metal wireway is intended to be part of a raceway, but could also be used as a pull box or junction box, etc. 

A wireway is not equipment. The NEC defines equipment as a general term, including fittings, devices, appliances, luminaires, apparatus, machinery and such used as a part of, or in connection with, an electrical installation. Fittings are accessories such as a locknut, bushing or other part of a wiring system intended primarily to perform a mechanical rather than an electrical function. The working space clearance requirements in 110.26(A) apply only to “equipment” operating at 1,000V, nominal, or less to ground, and likely to require examination, adjustment, servicing or maintenance while energized. Metal wireway is not equipment and likely will not require examination, adjustment, servicing or maintenance while energized.

GFCI in dwelling units

Does the NEC now require GFCI protection for the refrigerator in a kitchen? Are there any exceptions? Aren’t we going overboard here with GFCI? I just had another brand-new electric range trip the required GFCI because the receptacle (completely inaccessible by the way) was within 6 feet of the kitchen sink. We got zero help from the manufacturers. It is now on a standard circuit breaker.

If the refrigerator is in the kitchen and is plugged into a 125V through 250V receptacle, the 2023 NEC requires GFCI protection. The previous GFCI requirement for receptacles in dwelling unit kitchens was limited to receptacles installed to serve “countertop surfaces.” That text was deleted and list item 210.8(A)(6) is now a single word: kitchens. 

We have had other inquiries as to where the kitchen ends. The requirement for GFCI protection of receptacles does not apply entirely to the required small appliance branch circuits, which must supply the receptacle outlets in the kitchen, pantry, breakfast room, dining room and similar areas of a dwelling unit. These area units do not require GFCI protection for receptacles (unless within 6 feet of a sink), but the demarcation between these spaces may create confusion and misinterpretation. For example, where does the kitchen end and the breakfast room or dining room begin in an open floor configuration?

Power source for a fire pump 

I know that the normal source for a fire pump can be supplied by a service connection. Is there any circumstance where the NEC would allow for a fire pump to be supplied by a feeder supplied from the building’s electrical service?

There are provisions for an individual power source supplying a fire pump motor in Article 695 that permit a “dedicated feeder,” which must be supplied directly from the load side of a service disconnecting means that includes a dedicated transformer where the service is not at utilization voltage. Section 695.3 contains requirements for fire pump power sources and contains a general requirement in the parent text that power sources be “reliable.” Permitted individual sources are listed in 695.3(A). A direct connection to service conductors is permitted in 695.3(A)(1).

There are circumstances where a connection to service conductors is not feasible, including, but not limited to, service voltages at other than utilization voltage (e.g., a 15-kilovolt service) and existing buildings where installing service conductors through the building to the fire pump controller is not feasible. Where this occurs, a dedicated feeder is permitted in accordance with 695.3(A)(3). A dedicated feeder must be derived from a service connection. This means there is a service disconnecting means dedicated to the fire pump source. Note that where this occurs, the requirements of 695.6 apply and 2-hour fire-rated wiring methods may be required. Where the service connection is not recognized as reliable (see criteria in NFPA 20 sections 9.3.2 and A.9.3.2 for guidance on determining power source reliability) the requirements of 695.3(B) for multiple sources will apply, typically requiring an approved combination of one of the individual sources in 695.3(A) and an on-site standby generator.

Physical protection of GEC

Can schedule 40 PVC be used for physical protection of a 1/0 AWG copper grounding electrode conductor (GEC)? We failed a job because of that.

No, PVC conduit used for physical protection of a GEC must be schedule 80. Requirements for GECs are located in Part III of Article 250. See Section 250.64(B)(2), which requires a 6 AWG or larger GEC exposed to physical damage be protected by RMC, IMC, Schedule 80 PVC, RTRC-XW, EMT or cable armor.

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