GFCI requirements in the 2017 NEC cover 125-volt, single-phase, 15- and 20-ampere receptacles in 10 dwelling locations, 210.8(A)(1) through (10). A 240-volt dryer receptacle isn't on that list, and only the unfinished parts of a basement are. Tennessee, Nevada, Arizona and Kansas exams grade these 2017 answers.
A GFCI opens the circuit when current leaks to ground, for example through a person, and 210.8 requires the device itself to be readily accessible. Not sure your test uses this edition? Check JCR's list of exams that still use the 2017 NEC, skim the biggest 2020 NEC changes from 2017, or warm up with these 2017 NEC practice test questions. Testing on the 2020 NEC? Use the 2020 NEC GFCI guide with all 11 dwelling locations instead.
Is 210.8 on your 2017 NEC exam? In Tennessee, Nevada, Arizona and Kansas it is, and the 10-item list is the one that's graded. JCR's 2017 NEC package drills it along with the rest of the code.
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2017 NEC GFCI requirements for dwellings: the 10 locations in 210.8(A)
These apply to 125-volt, single-phase, 15- and 20-ampere receptacles in a dwelling unit:
| Location | Which receptacles need GFCI |
|---|---|
| 1. Bathrooms | All of them |
| 2. Garages and accessory buildings | All garage receptacles. Accessory buildings count when the floor is at or below grade, they aren't intended as habitable rooms, and they're limited to storage, work and similar uses. |
| 3. Outdoors | All of them. A receptacle that isn't readily accessible, on a branch circuit dedicated to snow-melting, deicing or pipeline and vessel heating equipment, may follow 426.28 or 427.22 instead. |
| 4. Crawl spaces | At or below grade level |
| 5. Unfinished basements | Unfinished portions or areas not intended as habitable rooms. A receptacle that supplies only a permanently installed fire alarm or burglar alarm system is exempt, but it doesn't count as the basement receptacle 210.52(G) requires. |
| 6. Kitchens | Receptacles installed to serve the countertop surfaces |
| 7. Sinks | Within 6 ft of the top inside edge of the sink bowl |
| 8. Boathouses | All of them |
| 9. Bathtubs or shower stalls | Within 6 ft of the outside edge of the tub or shower stall |
| 10. Laundry areas | All 125-volt, 15- and 20-ampere receptacles there |
Measure the 6 ft distances as the shortest path a cord would follow, without piercing a floor, wall, ceiling or fixed barrier, or passing through a door, doorway or window (210.8).
Commercial GFCI and the rest of 2017 NEC 210.8: (B) through (E)
210.8(B): other than dwelling units
Outside dwellings, the 2017 NEC already goes past 125 volts. It covers single-phase receptacles rated 150 volts to ground or less and 50 amperes or less, and three-phase receptacles rated 150 volts to ground or less and 100 amperes or less, in 10 locations:
- Bathrooms
- Kitchens
- Rooftops
- Outdoors
- Sinks, within 6 ft of the top inside edge of the bowl
- Indoor 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 level
- Unfinished portions or areas of basements not intended as habitable rooms
210.8(C): boat hoists
Outlets of 240 volts or less that supply boat hoists at dwelling units need GFCI. The rule says outlets, so a hard-wired hoist counts.
210.8(D): kitchen dishwasher branch circuit
Outlets that supply dishwashers in dwelling units need GFCI, whether the dishwasher is cord-and-plug connected or hard-wired.
210.8(E): crawl space lighting outlets
Lighting outlets of 120 volts or less in crawl spaces need GFCI. 210.8(A)(4) covers only receptacles, so this is the rule for the crawl space light.
2017 vs 2020 GFCI: basement, dryer and outdoor answers that flip
The 2017 answer is the one that gets scored on a 2017 exam. These are the questions where a 2020 habit costs you points:
| Situation (dwelling unless noted) | 2017 NEC | 2020 NEC |
|---|---|---|
| 30 A, 125/250 V dryer receptacle in the laundry | No GFCI. 210.8(A) covers only 125 V, 15 and 20 A receptacles. | GFCI. Covers 125 V through 250 V receptacles. |
| 50 A, 250 V receptacle in the garage | No GFCI under 210.8(A) | GFCI, 210.8(A)(2) |
| 125 V receptacle in a finished basement room | No GFCI. Only unfinished areas are listed. | GFCI. All basements are covered. |
| Hard-wired A/C condenser outdoors | No GFCI. The outdoor item covers receptacles only. | Covered by new 210.8(F), outdoor outlets |
| 125 V receptacle in an attic for servicing a furnace (210.63) | No GFCI. An attic isn't a 210.8(A) location. | GFCI, 210.8(E) |
| 125 V receptacle in an indoor damp or wet location not otherwise listed | No GFCI | GFCI, new item 210.8(A)(11) |
| 120 V crawl space lighting outlet | GFCI, 210.8(E) | GFCI, 210.8(C). Same answer, new letter. |
Worked example: one house under the 2017 NEC
A single-family house on a 120/240-volt service, scored on the 2017 NEC:
- Kitchen countertop receptacles: GFCI, 210.8(A)(6).
- Disposal receptacle in the sink base, 2 ft from the bowl: GFCI, 210.8(A)(7). The 2017 sink item doesn't exclude kitchens.
- Dishwasher outlet: GFCI, 210.8(D).
- Refrigerator receptacle 8 ft from the sink, not serving the counter: no GFCI.
- Washer receptacle, 125 V, 20 A, in the laundry room: GFCI, 210.8(A)(10).
- 30 A, 125/250 V dryer receptacle in the same room: no GFCI under 210.8(A).
- Receptacles in the finished basement family room: no GFCI under 210.8(A). AFCI is a separate rule (210.12).
- Receptacle in the unfinished basement storage area: GFCI, 210.8(A)(5).
- Garage freezer receptacle: GFCI, 210.8(A)(2). There's no appliance exception.
- 120 V crawl space light: GFCI, 210.8(E).
- Hard-wired A/C condenser: no GFCI in 2017. The service receptacle next to it is outdoors, so that receptacle needs GFCI under 210.8(A)(3).
2017 GFCI exam traps
- Reciting the 2020 list. Eleven locations, 250-volt receptacles and all basements are 2020. On a 2017 exam the dwelling list stops at 10 items and at 125 volts, 15 and 20 amperes.
- “Basement” vs. “unfinished basement.” A finished room needs GFCI in 2017 only if another item catches it, such as a sink, bathroom or laundry area.
- Kitchen sinks. Any receptacle within 6 ft of the kitchen sink bowl is covered by the sink item, even if it doesn't serve the counter.
- Receptacles vs. outlets. 210.8(A) covers receptacles only. In 2017, hard-wired outlets appear only in 210.8(C), (D) and (E).
- Carrying commercial amps into homes. The 150 V to ground, 50 A and 100 A scope belongs to 210.8(B) only.
- Replacements. A replacement receptacle where GFCI is now required must be GFCI protected (406.4(D)(3)).
2017 GFCI quiz: 5 questions
Use your 2017 code book, write down your answers, then check the key.
Question 1: Dryer receptacle
A dwelling laundry room has a 30-ampere, 125/250-volt receptacle for an electric dryer. Under the 2017 NEC, does 210.8(A) require GFCI protection for it?
- Yes, 210.8(A)(10) covers every laundry receptacle
- No, 2017 210.8(A) covers only 125-volt, 15- and 20-ampere receptacles
- Only if it is within 6 ft of a sink
- Only if the laundry is in a garage
Question 2: Finished basement
A 20-ampere, 125-volt receptacle is in a finished basement recreation room, 20 ft from any sink. Under 2017 NEC 210.8(A), this receptacle:
- needs GFCI under 210.8(A)(5)
- needs GFCI because it is below grade
- does not need GFCI under 210.8(A)
- needs GFCI under 210.8(A)(4)
Question 3: Dishwasher
Which 2017 NEC section requires GFCI protection for the outlet that supplies a dishwasher in a dwelling unit?
- 210.8(A)(6)
- 210.8(C)
- 210.8(D)
- 422.5(A)
Question 4: Crawl space light
A 120-volt lighting outlet is installed in a dwelling crawl space. Which 2017 NEC rule requires GFCI protection for it?
- 210.8(A)(4)
- 210.8(C)
- 210.8(E)
- None, lighting outlets are exempt
Question 5: Commercial kitchen
A restaurant kitchen has a 30-ampere, 208-volt, single-phase receptacle fed from a 208Y/120-volt system. Under the 2017 NEC:
- No GFCI is needed, because 210.8(B) covers only 125-volt receptacles
- GFCI is required by 210.8(B)(2)
- GFCI is required only within 6 ft of a sink
- GFCI is required only if the receptacle is outdoors
Answer key
Show answer 1Hide answer 1
1. B, no (2017 NEC 210.8(A))
The 2017 dwelling rule opens with 125-volt, single-phase, 15- and 20-ampere receptacles. A 30-ampere, 125/250-volt dryer receptacle doesn't meet that description, so the laundry item never applies to it. Answer A is the 2020 answer: the 2020 NEC covers 125-volt through 250-volt receptacles.
Show answer 2Hide answer 2
2. C, no GFCI under 210.8(A) (2017 NEC 210.8(A)(5))
2017 210.8(A)(5) covers only unfinished portions or areas of the basement not intended as habitable rooms. The rec room is finished, and nothing else on the list applies. 210.8(A)(4) is crawl spaces, not basements. The 2020 NEC dropped “unfinished,” so on a 2020 exam the answer would be A.
Show answer 3Hide answer 3
3. C, 210.8(D)
2017 210.8(D), Kitchen Dishwasher Branch Circuit, requires GFCI for outlets that supply dwelling dishwashers. It says outlets, so a hard-wired dishwasher counts. 210.8(A)(6) covers only receptacles that serve the countertop, and 210.8(C) is boat hoists. The 422.5(A) appliance list is the 2020 route.
Show answer 4Hide answer 4
4. C, 210.8(E)
2017 210.8(E) requires GFCI for lighting outlets rated 120 volts or less in crawl spaces. 210.8(A)(4) covers crawl space receptacles only. In the 2020 NEC the same rule moved to 210.8(C), so watch the letter.
Show answer 5Hide answer 5
5. B, GFCI is required (2017 NEC 210.8(B)(2))
Outside dwellings, 2017 210.8(B) covers single-phase receptacles rated 150 volts to ground or less and 50 amperes or less. Each ungrounded conductor of a 208Y/120-volt system is 120 volts to ground, and the receptacle is 30 amperes, so the kitchen item applies.
2017 NEC GFCI requirements FAQ
How many dwelling GFCI locations are in the 2017 NEC?
Ten. 2017 NEC 210.8(A)(1) through (10) lists bathrooms, garages and accessory buildings, outdoors, crawl spaces, unfinished basements, kitchen countertops, sinks, boathouses, bathtubs and shower stalls, and laundry areas. Indoor damp and wet locations became the 11th item in the 2020 NEC.
Do all basement receptacles need GFCI under the 2017 NEC?
No. 2017 NEC 210.8(A)(5) covers only unfinished portions or areas of the basement not intended as habitable rooms. A finished basement receptacle needs GFCI only if another item catches it, such as being within 6 ft of a sink or in a laundry area.
Does a 240-volt dryer receptacle need GFCI under the 2017 NEC?
Not under 210.8(A). The 2017 dwelling rule covers only 125-volt, single-phase, 15- and 20-ampere receptacles, so a 30-ampere, 125/250-volt dryer receptacle is outside it. The 2020 NEC changed this answer.
Lock in 210.8 before test day
GFCI questions are quick points once you know which list your exam uses. Check yourself, then work through the full 2017 code.
The free mock is 25 questions with an email sign-up, and every answer shows its NEC section. The $495 2017 NEC self-study package adds the timed 100-question mock, the printed manual, 100 video lessons and permanent tabs, and there's a Tennessee version too.
Sources
- NFPA 70, National Electrical Code, 2017 edition
- 2017 NEC 210.8(A) through (E)
- 2017 NEC 210.52(G), 406.4(D)(3), 426.28 and 427.22
- 2020 NEC 210.8, for the comparison table
Reviewed November 6, 2026. NEC references are to the 2017 edition.
