5.2 GFCI & AFCI Protection Requirements (NEC 210.8 & 210.12)

Two devices, two hazards

A Class A GFCI compares the current on the ungrounded and grounded conductors. If current returns through a person or another path to ground, the imbalance trips the device. Its trip time is inverse: the larger the leakage current, the faster it opens. A GFCI does not protect against a line-to-neutral shock, because that current returns on the neutral and causes no imbalance.

Do not confuse a GFCI with ground-fault protection of equipment (GFPE). GFPE protects equipment from destructive ground faults at much higher current settings, such as the service GFPE required by 230.95 for 1000 A or larger solidly grounded wye services over 150 V to ground. Article 100 also defines special-purpose GFCIs (SPGFCIs) for personnel protection on circuits above 150 V to ground, where the Code calls for them.

An AFCI detects parallel arcs (between conductors) and series arcs (across a break in one conductor, such as a loose terminal or a damaged cord). A series arc draws no more than the load current, so a standard breaker never sees it.

Dwelling units: 210.8(A)

GFCI protection is required for 125- through 250-volt receptacles supplied by single-phase branch circuits rated 150 volts or less to ground in these dwelling locations:

Measuring 6 ft: the distance is the shortest path the supply cord of an appliance plugged into the receptacle would follow without piercing a floor, wall, ceiling, or fixed barrier, or passing through a door, doorway, or window. The GFCI device itself must be installed in a readily accessible location.

Specific equipment and outdoor outlets

• 210.8(D): outlets supplying the appliances listed in 422.5(A), such as dishwashers, vending machines, drinking water coolers and bottle fill stations, tire inflation and automotive vacuum machines, and cord-and-plug-connected high-pressure spray washers, need GFCI protection unless the appliance provides it.
• 210.8(E): the HVAC service receptacle required by 210.63 must be GFCI protected.
• 210.8(F), 2026 NEC: dwelling outdoor outlets (not just receptacles) rated 60 A or less on single-phase circuits of 150 V or less to ground need GFCI protection. This covers hard-wired equipment such as air conditioners, heat pumps, and pool heaters. The 2023 edition used 50 A. A temporary exception for listed HVAC equipment applied only before September 1, 2026. A new exception, with no expiration date, permits a listed Class C SPGFCI to protect listed HVAC equipment instead of a Class A GFCI.

Other than dwelling units: 210.8(B)

GFCI protection is required for receptacles supplied by single-phase branch circuits rated 150 V or less to ground, 50 A or less, and three-phase branch circuits rated 150 V or less to ground, 100 A or less, in locations including:

• bathrooms;
• kitchens, and other areas with a sink and permanent provisions for food or beverage preparation or cooking;
• rooftops;
• outdoors;
• within 6 ft of sinks;
• indoor damp and wet locations;
• locker rooms with associated showering facilities;
• garages, service bays, and similar areas, other than vehicle exhibition halls and showrooms;
• crawl spaces at or below grade, and unfinished areas of basements;
• aquariums, bait wells, and similar open aquatic vessels or containers, for receptacles within 6 ft of the top inside edge.

AFCI protection: 210.12

Where it is required

210.12(A): all 120-volt, single-phase, 10-, 15-, and 20-ampere branch circuits supplying outlets or devices installed in dwelling unit kitchens, family rooms, dining rooms, living rooms, parlors, libraries, dens, bedrooms, sunrooms, recreation rooms, closets, hallways, laundry areas, or similar rooms or areas. Because the rule says "outlets," it covers lighting outlets, smoke alarm outlets, and hard-wired appliances as well as receptacles. Bathrooms, garages, and outdoor circuits are not on the list.

Sections 210.12(B) and (C) extend AFCI protection to dormitory units and to guest rooms, guest suites, and patient sleeping rooms in nursing homes and limited-care facilities.

Permitted methods

The Code lists several methods. The two most common are:

1. a listed combination-type AFCI circuit breaker at the origin of the branch circuit; and
2. a listed outlet branch-circuit (OBC) AFCI at the first outlet, where the wiring from the panelboard to the first outlet box is in RMC, IMC, EMT, Type MC cable, or steel-armored Type AC cable with metal boxes, or is PVC, RTRC, or ENT encased in at least 2 in. of concrete.

Other combinations, such as a branch/feeder AFCI with an OBC AFCI at the first outlet, have specific conditions in 210.12(A).

Extensions and modifications: 210.12(E)

Where branch-circuit wiring in any area listed in 210.12(A), (B), or (C) is modified, replaced, or extended, the branch circuit must be protected by a combination-type AFCI at its origin or a listed OBC AFCI at the first receptacle outlet or, new in the 2026 NEC, the first switch of the existing branch circuit. (This rule was 210.12(D) in the 2023 edition.) The exception: AFCI protection is not required where the extension is not more than 6 ft and does not add any outlets or devices, other than splicing devices.

Article 406, which the 2026 NEC renamed "Wiring Devices," adds parallel rules for replacing receptacles: a replacement in a location where the current Code requires GFCI or AFCI protection must be given that protection.

Combined protection

Where both are required, use a dual-function breaker or another listed combination, such as a combination AFCI breaker feeding a GFCI receptacle.

Worked scenarios

Scenario 1 — Hallway receptacle. A receptacle in a hallway is 5 ft from the kitchen sink in a straight line, but a full-height wall separates them, and the only cord path passes through a doorway. Because the measurement may not pierce a wall or pass through a doorway, the receptacle is not within 6 ft of the sink for 210.8 purposes. It still needs AFCI protection because it is in a hallway.

Scenario 2 — Bedroom extension. An electrician extends an existing bedroom circuit 10 ft to add a receptacle. The extension exceeds 6 ft and adds an outlet, so 210.12(E) requires a combination AFCI breaker at the panel or a listed OBC AFCI at the first receptacle outlet or first switch of the existing circuit.

Scenario 3 — New condenser. A new 40 A heat pump outdoor unit is installed at a single-family home in October 2026. Under 210.8(F), the outdoor outlet must be GFCI protected, because the temporary HVAC exception expired September 1, 2026. Where the listed equipment is not compatible with a Class A GFCI, a listed Class C SPGFCI may be used.