2.5 Switches, Receptacles & Wiring Devices (NEC Articles 404 & 406)
Key Takeaways
- NEC 404.2(C) requires a grounded conductor to be provided at the switch location for switches controlling lighting loads, with limited exceptions such as raceway sufficiently sized for a future grounded conductor or cable with an accessible spare.
- NEC 404.8(A) limits the center of the grip of a switch operating handle in its highest position to not more than 2.0 m (6 ft 7 in) above the floor or working platform.
- NEC 406.4(D) governs receptacle replacement and can require a grounding type, GFCI, AFCI, tamper-resistant, or weather-resistant device depending on where the replacement occurs.
- NEC 406.5(E) prohibits receptacles from being installed in a face-up position in or on countertop or work surfaces, and 406.9(B) requires an enclosure that is weatherproof whether or not an attachment plug is inserted for 15- and 20-ampere 125- and 250-volt receptacles in wet locations.
- NEC 406.9(C) prohibits receptacles from being installed within a bathtub or shower space, a zone the 2023 NEC continues to police alongside the luminaire and fan restrictions of 410.10(D).
2.5 Switches, Receptacles & Wiring Devices (NEC Articles 404 & 406)
Exam Focus: 404.2(C) grounded conductor at the switch, 404.8(A) handle height, 406.4(D) replacement rules, 406.5 mounting and the face-up prohibition, 406.9 damp and wet locations, and the bathtub/shower zone.
Sections 2.1 through 2.4 sized the circuit and located the outlets. This section covers the devices that land on those outlets. Article 404 governs switches, Article 406 governs receptacles, cord connectors, and attachment plugs.
Switches — Article 404
The Grounded Conductor at the Switch (404.2(C))
Where a switch controls a lighting load, the grounded (neutral) conductor must be provided at the switch location. The reason is practical: electronic dimmers, timers, occupancy sensors, and smart switches need a neutral to power their electronics, and without one they leak current through the equipment grounding conductor.
Limited exceptions permit omitting the grounded conductor where:
- Conductors enter the box through a raceway with sufficient cross-sectional area to accept a future grounded conductor; or
- Cable assemblies enter the box through a framing cavity that is open at the top or bottom on the same floor level, or through a wall, floor, or ceiling that is unfinished on one side.
Switch Mounting and Position
| Rule | Requirement |
|---|---|
| 404.8(A) | The center of the grip of the operating handle, in its highest position, must be not more than 2.0 m (6 ft 7 in) above the floor or working platform |
| 404.7 | Single-throw knife switches must be placed so gravity will not close them; general-use switches must clearly indicate on/off position |
| 404.9(B) | Metal faceplates must be grounded; snap switches must be effectively grounded and provide a means to ground the metal faceplate |
| 404.4 | Switches in damp or wet locations must be in a weatherproof enclosure |
| 404.2(A) | Three-way and four-way switches must switch only the ungrounded conductor |
[!CAUTION] Never switch the grounded conductor. Switching the neutral leaves the luminaire energized to ground even when the switch is off. This is one of the few code rules that produces a fatality when ignored, and it appears on licensing exams in troubleshooting form.
Receptacles — Article 406
Mounting and Position (406.5)
| Rule | Requirement |
|---|---|
| 406.5(A)–(C) | Receptacles must be mounted in boxes or assemblies designed for the purpose; boxes set back in noncombustible surfaces may not be set back more than 6 mm (1/4 in) |
| 406.5(E) | Receptacles must not be installed in a face-up position in or on countertop or work surfaces |
| 406.5(F) | Receptacles must not be installed in a face-up position in seating areas or similar surfaces unless listed for that application |
| 406.5(G) | Receptacles installed in a face-up position in a floor require an assembly listed for floor use |
| 406.4(G) | Floor receptacles are subject to protection requirements added in the 2023 NEC |
The face-up prohibition exists because a face-up receptacle collects liquid, crumbs, and metal debris. The permitted alternative for an island or peninsula is a listed pop-up or countertop assembly, which is why the 2023 island rules in 210.52(C) reference listed assemblies.
Damp and Wet Locations (406.9)
| Location | Required Enclosure |
|---|---|
| Damp location | An enclosure weatherproof when the attachment plug is removed |
| Wet location — 15 A and 20 A, 125 V and 250 V | An enclosure weatherproof whether or not the attachment plug is inserted — the "in-use" or bubble cover |
| Wet location — other receptacles | An enclosure weatherproof when the plug is removed, where the receptacle is not likely to be used with a cord left connected |
Covers must be capable of opening at least 90 degrees, or fully open where the cover is not designed to open 90 degrees.
The Bathtub and Shower Space (406.9(C))
Receptacles shall not be installed within a bathtub or shower space. Pair this with 410.10(D), which in the 2023 NEC prohibits a ceiling-suspended fan with a light kit within a zone measured 3 ft horizontally and 8 ft vertically from the top of the bathtub rim or shower stall threshold.
Receptacle Replacement — NEC 406.4(D)
Replacing a receptacle is not always a like-for-like operation. Six separate triggers can attach:
| 406.4(D) Subsection | Trigger |
|---|---|
| (1) | Where a grounding means exists in the box, the replacement must be a grounding-type receptacle connected to the equipment grounding conductor |
| (2) | Where no grounding means exists, the replacement may be (a) another non-grounding type, (b) a GFCI type marked "No Equipment Ground", or (c) a grounding type supplied through a GFCI and marked "GFCI Protected" and "No Equipment Ground" |
| (3) | Where the location now requires GFCI protection under 210.8, the replacement must be GFCI protected |
| (4) | Where the location now requires AFCI protection under 210.12, the replacement must be AFCI protected — in dwelling units, dormitory units, guest rooms and guest suites, and patient sleeping rooms of nursing homes and limited-care facilities |
| (5) | Where tamper-resistant receptacles are required by 406.12, the replacement must be tamper resistant |
| (6) | Where weather-resistant receptacles are required by 406.9(A) and (B), the replacement must be weather resistant |
[!IMPORTANT] The replacement rules are how the NEC upgrades existing buildings. A homeowner replacing a broken kitchen receptacle in a 1968 house triggers 210.8 GFCI protection under 406.4(D)(3) even though nothing else in the kitchen changes. Bootleg grounding — jumping the neutral to the ground screw — is never a permitted method and creates an energized equipment ground.
Faceplates, Night Lights, and USB Chargers
- 406.6 requires faceplates to completely cover the opening and seat against the mounting surface.
- 406.6(D) addresses receptacle faceplates with an integral night light or USB charger, which must be listed and, where they contain electronics, supplied through the receptacle's own terminals.
- 406.3(D) requires that receptacles be listed and marked with the manufacturer's identification and ratings.
Where a switch controls a lighting load in a dwelling, what does NEC 404.2(C) require to be present at the switch location?
A receptacle is being installed to serve a kitchen island in a dwelling. Which installation does NEC 406.5(E) prohibit?
A 20-ampere, 125-volt receptacle is installed on an exterior wall in a wet location where a cord may be left plugged in. What enclosure does NEC 406.9(B) require?
A homeowner replaces a damaged receptacle located within 6 feet of a kitchen sink in a house wired in 1968. The box contains an equipment grounding conductor. What does NEC 406.4(D) require?