Receptacle Types Practice Questions

C. The rating, type and installation of wiring devices

The article is titled for wiring devices rather than receptacles alone, and that matters this cycle because general-use snap switches, dimmers and electronic control switches were moved in from Article 404 as a new third part. So section numbers taken from a 2023 source do not carry across. Placement of receptacle outlets stays in the branch circuit article.

NEC 2026 406.1, 406.30

A. Wiring devices are required to be listed

This is one short sentence at the second section of the article, which is where the 2026 edition put listing requirements throughout the book. It reaches wiring devices generally, so it takes in the switches that moved into this article as well as the receptacles. An option that narrows it by rating or by location is wrong on its face.

NEC 2026 406.2

D. Reconditioned wiring devices are not permitted to be installed

The third section of the article is a flat prohibition rather than a set of conditions, which is unusual and therefore worth carrying. Other articles in the 2026 book put conditions on reconditioned equipment at the same section position, so an item can test whether you know this one says no outright. Read the third section of any article before assuming reconditioning is a marking question.

NEC 2026 406.3

B. A surface-mounted switch is enclosed in a weatherproof enclosure, and a flush-mounted switch is equipped with a weatherproof cover

The 2026 edition writes this article for wiring devices generally rather than for receptacles alone, so the damp and wet location triggers catch the switch on the same wall. Surface mounting and flush mounting get different answers in the same short list. The enclosure for the surface-mounted case complies with the construction rules for cabinets and cutout boxes.

NEC 2026 406.9(A), 406.30

C. An enclosure that is weatherproof when the attachment plug is removed

The general wet location rule keeps the enclosure weatherproof whether or not a plug is inserted, which is what makes an in-use cover necessary. This exception runs the other way for one condition, since the thing it assumes will not happen is a cord left plugged in under a pressure washer. It reaches 15- and 20-ampere receptacles from 125 through 250 volts, and it does nothing to the separate requirement that the device itself be the weather-resistant type.

NEC 2026 406.9(B)

A. It is listed and identified as extra duty

The extra duty identification attaches to the outlet box hood specifically. Other listed products, enclosures or assemblies that give weatherproof protection without using an outlet box hood do not have to carry it, and the section says so in the next sentence. Hinged covers on these hoods also have to open at least 90 degrees, or fully open where the design does not allow 90.

NEC 2026 406.9(B)

D. All 15- and 20-ampere, 125- and 250-volt nonlocking-type receptacles

The trigger reaches both voltage classes and both current ratings, and the word nonlocking is what keeps locking devices out of it. An informational note names the four configurations covered. Other receptacles in wet locations are separately required to be the listed weather-resistant type as well, so the answer is not that the rule is narrow.

NEC 2026 406.9(B)

B. A damp location is protected from weather and not subject to saturation but has moderate moisture, while a wet location is unprotected and exposed to weather, subject to saturation, underground, or in concrete or masonry in direct contact with the earth

Both terms are defined rather than left to judgment, which is why an item that describes a canopy, a marquee or a roof overhang is testing a definition. The wet definition is a list of four conditions and any one of them is enough, including underground and in a slab in contact with earth. Anything suitable for a wet location is also considered suitable for a damp one.

NEC 2026 Article 100, 406.9(A)

C. Inside the tub or shower, or within a zone reaching 3 feet horizontally from any outside edge and vertically from the floor to 8 feet above the tub rim or shower threshold

The prohibited zone is a box rather than a radius, with a horizontal reach and a vertical reach stated separately, and it takes in the space directly over the tub and the space below the zone. It stops at a floor, wall, ceiling, room door, window or fixed barrier. Four exceptions follow, including one for a small bathroom where the receptacle required by the branch circuit article can go opposite the tub rim on the farthest wall.

NEC 2026 406.9(C)

A. Copper conductors, copper-clad aluminum conductors, or both, in the branch-circuit conductor sizes the manufacturer identifies

The marking is what permits a direct aluminum termination, so a device without it may not take aluminum at all. Copper and copper-clad aluminum are still fine on an unmarked device, within the sizes the manufacturer identifies. This is also the reason a replacement on an existing aluminum branch circuit gets its own carve-out in the tamper-resistant replacement rules.

NEC 2026 406.10, 406.12(D)

D. Not less than 15 amperes at 125 volts, or 15 amperes at 250 volts, and of a type not suitable for use as a lampholder

Two facts in one sentence and the second is the one people skip: the device may not be a type that will take a lamp. Receptacles also carry the manufacturer name or identification and the voltage and ampere ratings on the device itself. Where the device sits on a branch circuit with two or more receptacles, a table in the branch circuit article decides which ratings are permitted.

NEC 2026 406.11(B), 210.21(B)

B. By an orange triangle located on the face of the receptacle

The identification is a triangle on the face and the color is orange, which is a pair of facts an item can split. The device is used only with equipment grounding conductors isolated in the way the grounding article permits. Where one is installed in a nonmetallic box it gets a nonmetallic faceplate, unless the box has a feature that lets a metal plate be connected to the equipment grounding conductor.

NEC 2026 406.11(C)

C. A permanent marking with the symbol the article prints and the word that names it as controlled

The marking is permanent and it sits on the device, since the point is to warn somebody plugging something in that the outlet may go dead on a schedule. The rule reaches nonlocking 125-volt, 15- and 20-ampere receptacles that are controlled or that carry control features that remove power for energy management or building automation. Where automatic control is later removed, the replacement rules call for devices and faceplates without that marking.

NEC 2026 406.11(D), 406.12(D)

A. The grounding type, except where the replacement provisions permit otherwise

The requirement is general and its single exit is the replacement subsection, which handles existing boxes with no equipment grounding conductor in them. A grounding-type receptacle also goes only on circuits of the voltage class and current for which it is rated, subject to the ratings rules in the branch circuit article. The equipment grounding contacts have to be connected to an equipment grounding conductor.

NEC 2026 406.12(A), 406.12(B)

D. They are of a design that keeps the attachment plugs used on those circuits from being interchangeable

Configuration is a physical fact stamped into the device, and this is the rule that explains why. The trigger is different voltages, different frequencies or different types of current, direct or alternating, on the same premises. A separate section carries the general noninterchangeability requirement for receptacles, cord connectors and attachment plugs.

NEC 2026 406.12(F), 406.20

B. The equipment grounding connection is made before the current-carrying connections, and grounding poles cannot reach current-carrying parts

Making ground first and breaking it last is a sequencing requirement written into the physical design of the device rather than into the installation. The same section identifies the terminal for connection to the grounding pole, by a green hexagonal-headed or shaped screw, a green pressure wire connector body, or a similar green device on an adapter. Grounding terminals are not used for anything other than connection to equipment grounding conductors.

NEC 2026 406.19, 406.19(D)

C. Another nongrounding-type receptacle, a ground-fault circuit-interrupter type marked to show there is no equipment ground, or a grounding-type receptacle supplied through a ground-fault circuit interrupter and marked both ways

Three named ways out and each carries its own marking, so this is a passage to read in place rather than to carry from memory. In both of the ground-fault options the equipment grounding terminal is not carried on to downstream outlets or between the grounding-type receptacles. An item will offer you a near miss of one of the three.

NEC 2026 406.12(D)

A. Ground-fault protection is provided at the replacement, unless three stated conditions about box size and upstream options are all met

Replacement is treated as new work, which is the rule most working electricians are surprised by and therefore a favorite for item writers. The exception is narrow and all three of its conditions have to hold at once: the box will not take a device, no upstream box will either, and a breaker cannot do the job. Any one condition failing puts you back under the requirement.

NEC 2026 406.12(D)

D. A listed outlet branch-circuit type device, a receptacle protected by one, or a receptacle protected by a listed combination type device

Three ways to satisfy it and two of them protect the outlet from somewhere else in the circuit rather than at the device. Substituting ground-fault protection does not answer an arc-fault requirement, which is what the second wrong answer is built on. Where a stem names the room, check the arc-fault section in the branch circuit article before you decide the requirement applies.

NEC 2026 406.12(D), 210.12

B. Where a nongrounding receptacle is replaced with another nongrounding receptacle, or where aluminum branch-circuit conductors are directly terminated on CO/ALR receptacles installed as replacements

Two cases and both are about what the existing wiring will physically accept rather than about the age of the building. Age is never a defense in the replacement provisions, which is the point of having them. The weather-resistant, controlled and ground-fault protection of equipment requirements all get parallel replacement paragraphs in the same list.

NEC 2026 406.12(D)

C. All 15- and 20-ampere, 125- and 250-volt nonlocking-type receptacles in the named locations

Two current ratings, two voltage classes, and the word nonlocking, which is stated in the first line of the section and is easy to read past. Locking receptacles sit outside the requirement entirely. Everything else turns on whether the location is on the list rather than on anything about the room.

NEC 2026 406.26

A. Park and recreation areas

The list runs to eleven entries and this one was added for this cycle, with an informational note that names garden areas and play areas as examples. Reasoning from whether small children are likely to be present will lose you items, because the list also reaches fitness centers, skating rinks, places of awaiting transportation and areas of agricultural buildings open to the public. Read the building type in the stem, then go and look at the list.

NEC 2026 406.26

B. Physical protection that lets floor-cleaning equipment be operated without damaging the receptacles, plus ground-fault protection for 125-volt, single-phase, 15- and 20-ampere floor receptacles in food courts and in waiting spaces of passenger transportation facilities

Two separate obligations sit in one short subsection, and the second is tied to two named kinds of space rather than to floors generally. A stem set in an airport concourse or a mall food court is pointing at the second one. Note that a floor receptacle also has its own rule in the branch circuit article about whether it counts toward the required outlets.

NEC 2026 406.12(G), 210.52(A)(3)

D. They are installed to completely cover the opening and to seat against the mounting surface

Two conditions and both are about closing the opening: full coverage and a seat against the surface. Faceplates or cover plates mounted inside boxes with recess-mounted receptacles get the same treatment stated separately. This is a short section that produces easy points when it appears.

NEC 2026 406.16

A. They moved into the wiring devices article as a new third part covering snap switches, dimmers and electronic control switches

The move is the reason a section number for a switch rule taken from a 2023 source does not land where you expect. The switch connection rules about three-way and four-way wiring, about not disconnecting the grounded conductor, and about the grounded conductor at switch locations all sit in this article now. Article 100 still holds the definitions, so a definition question is unaffected by the move.

NEC 2026 406.30, 406.32