April NEC Questions and Answers

By Mike Holt for EC&M Magazine

Q1. Can a GFCI type receptacle be installed on an AFCI protected circuit?
A1. Sure. As a matter of fact, some manufacturers have listed circuit breakers that incorporate both GFCI and AFCI protection.

Q2. Is GFCI protection required for a single-phase, 208V, 30A coffee maker receptacle in a commercial kitchen?
A2. No, only 15 and 20A, 125V receptacles installed in commercial kitchens need to be GFCI protected [210.8(B)(2)].

Q3. What are the NEC rules for splicing copper and aluminum conductors together?
A2. Copper and aluminum conductors must not make contact with each other, except within a device that is listed and identified for this purpose [110.14].

Q4. Am I required to “pigtail” conductors at receptacles and switches, or can the screws provided on the devices be used to maintain the circuit continuity?
A4. Conductor pigtailing is generally not required, but the continuity of the grounded (neutral) conductor of a multiwire branch circuit must not be interrupted by the removal of a wiring device. Therefore, the grounded (neutral) conductors of multiwire branch circuits must be spliced together, and a pigtail must be provided for the wiring device [300.13(B)].

Q5. Can I use MC Cable for luminaires located at 8’ above a patient care area?
A5. Branch circuits that serve patient care areas must be installed in a metal raceway or listed cable with a metallic armor or sheath that qualifies as an effective ground-fault current path in accordance with 250.118.

Typically, the outer metal sheath of interlocked Type MC Cable isn’t listed as a suitable ground-fault current path [250.118(10]). Therefore, it is not permitted to supply branch circuits in patient care areas of health care facilities.

However, the metal armored sheath of Type AC cable is listed as a suitable ground-fault current path (it contains an internal bonding strip in direct contact with the metal sheath of the cable [250.118(8)]) and it can be used.

Author’s Comment: Patient care areas include patient rooms as well as examining rooms, therapy areas, examining and treatment rooms, recreational areas, and some patient corridors. See 517.2.

Q6. What is the minimum distance a receptacle must be located away from a sink?
A6. The NEC doesn’t specify a minimum distance that a receptacle must be located from a sink. However in dwelling units, GFCI protection is required for all 15 and 20A, 125V receptacles located within an arc measurement of 6 ft from the dwelling unit laundry, utility, or wet bar sink [210.8(A)(7)].

Q7. Is an air duct permitted to be installed directly above an electrical panel?
A7. No, the footprint space (width and depth of the equipment) extending from the floor to a height of 6 ft above the equipment or to the structural ceiling, whichever is lower, must be dedicated for the electrical installation. No piping, duct, or other equipment foreign to the electrical installation can be installed in this dedicated footprint space [110.26(F)].

Q8. Can the service disconnect be located within 5’ of a pool or hot tub?
A8. No. Circuit breakers, time clocks, pool light switches, and other switching devices must be located not less than 5 ft horizontally from the inside walls of a permanently installed pool, outdoor spa, or outdoor hot tub unless separated by a solid fence, wall, or other permanent barrier [680.22(C)]

Q9. Can I install Type NM Cable inside a raceway?
A9. Yes, but the cable must be protected from abrasion by a fitting installed on the end of the raceway [300.15(C)].

Q10. Does the NEC address the height of wiring devices, such as receptacles and light switches in a commercial building?
A10. No, the NEC doesn’t address where switches and receptacles are to be located, but commercial occupancies may require the devices to be accessible to disabled persons in accordance with the American Disabilities Act.