Special occupancies and equipment

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1. 1 · Special occupancies and equipment · NEC Knowledge

   A room is marked Class I because a flammable vapor may be present. During normal operation the vapor is there often enough that the equipment has to be suited for that, not only for an accident. Which designation fits the normal-operation case?

   1. A. Class I, Division 1. The hazard is present in normal operation, not only when something fails.Keyed answer
   2. B. Class I, Division 2. Division 2 means the hazard is present during normal operation.
   3. C. Class II. Flammable vapors are a dust classification.
   4. D. Unclassified, because a room label removes the hazard.

   Article 500 is where the class and division language starts. Division 1 is the normal-operation hazard. Division 2 is the case where the hazard shows up when something fails or is abnormal. Class II is combustible dust, not a vapor. Confirm the definitions in NEC 2026 before you pick a wiring method.

   Open NEC 2026 Article 500

2. 2 · Special occupancies and equipment · NEC Knowledge

   In a Class I location, a flammable gas or vapor is expected in the air during normal operation, not only when equipment fails. Which designation fits that description?

   1. A. Division 1Keyed answer
   2. B. Division 2
   3. C. An unclassified dry location
   4. D. A Class III location

   Division 1 is the tighter Class I condition, where the hazard is expected in normal operation. Division 2 is where the hazard shows up mainly under abnormal conditions. Class III is fibers and flyings, not a gas. Article 500 sets out the designations. Read the descriptions in NEC 2026.

   Open NEC 2026 Article 500

3. 3 · Special occupancies and equipment · NEC Knowledge

   An indoor spa is installed in a dwelling bathroom. The helper uses only the ordinary bathroom receptacle rules and skips the spa bonding and the receptacle rules written for the spa. Why is the bathroom rule not enough?

   1. A. A spa brings the pool and spa article in on top of the bathroom rules. Bonding and the receptacles near the spa are in that article.Keyed answer
   2. B. An indoor spa is exempt from bonding because the room has a roof.
   3. C. Bathroom rules replace the spa rules for any water in a house.
   4. D. A spa is a Class I location and uses no bonding.

   Article 680 covers indoor spas, including bonding and the receptacles around them. Article 210 still applies to the bathroom, but it does not replace the spa rules. Confirm the spa part of Article 680 in NEC 2026.

   Open NEC 2026 Article 680

4. 4 · Special occupancies and equipment · NEC Knowledge

   The replacement pool pump was left on an ordinary breaker. The helper says the old pump never had ground-fault protection, so a replacement keeps that omission and only a new pool would need the device. What still protects the replacement?

   1. A. Nothing. A replacement pump is prohibited from having ground-fault protection.
   2. B. The equipment grounding conductor alone, which is the ground-fault device for a pump.
   3. C. Ground-fault protection for the pool pump. Replacing the motor does not preserve the missing protection.Keyed answer
   4. D. A bathroom receptacle rule, because every pool is wired as a dwelling bathroom.

   Article 680 requires ground-fault protection for the pool pump motor. A previous omission does not become the rule for the replacement. Confirm the pump requirement in NEC 2026.

   Open NEC 2026 Article 680

5. 5 · Special occupancies and equipment · NEC Knowledge

   This permanently installed gunite pool was called storable because the helper wanted to skip the bonding grid. The shell is part of the structure, not a seasonal product he can fold up. What label did he apply to the wrong pool?

   1. A. Storable. A permanent shell does not become storable by the label. The permanent-pool bonding rules still apply. Confirm the storable limits in NEC 2026 before using that label.Keyed answer
   2. B. Permanently installed, which would have been the label that waives bonding.
   3. C. A fountain label, which removes both bonding and ground-fault protection.
   4. D. A bathroom label, which is the classification for every gunite shell.

   Article 680 treats a permanently installed pool under the permanent-pool rules. Calling it storable does not change the shell. Confirm the storable-pool limits in NEC 2026 rather than inventing them.

   Open NEC 2026 Article 680

6. 6 · Special occupancies and equipment · NEC Knowledge

   This indoor spa is treated as an ordinary bathtub. The helper says indoors means the bathroom receptacle rules are the only rules, and a spa inside the house has no pool-article duty. What did the roof over the spa fail to remove?

   1. A. The need for any ground-fault protection, which is prohibited on an indoor spa.
   2. B. Bonding, which is required only for outdoor fountains and never for a spa.
   3. C. The listing of the spa, which is optional once the tub is indoors.
   4. D. The spa rules. An indoor installation does not turn the spa into a plain bathtub or into a bathroom receptacle circuit.Keyed answer

   Article 680 still applies to this indoor spa. The bathroom branch-circuit rules do not replace it. Confirm the indoor spa requirements in NEC 2026.

   Open NEC 2026 Article 680

7. 7 · Special occupancies and equipment · NEC Knowledge

   The concrete deck around this permanently installed pool was skipped for equipotential bonding. The helper bonded the pump motor only and says the deck is landscaping, not electrical equipment, so the perimeter is outside the grid. What surface is still part of the bond?

   1. A. No surface. Equipotential bonding stops at the pump lug and never reaches a deck.
   2. B. The perimeter surface the equipotential rules include. Landscaping is not a reason to stop the grid at the waterline.Keyed answer
   3. C. Only a metal ladder, and a concrete deck is prohibited from being bonded.
   4. D. The bathroom tile inside the house, which is the perimeter the pool article means.

   Article 680 includes the perimeter surface in the equipotential bonding of a permanently installed pool. Confirm how that surface is bonded in NEC 2026. The pump lug is not the whole grid.

   Open NEC 2026 Article 680

8. 8 · Special occupancies and equipment · NEC Knowledge

   The poolside receptacle was spaced from the water with the kitchen-counter dimension the helper had memorized. He says a receptacle near water uses the kitchen rule, whether the water is a sink or a pool. What is wrong with that dimension?

   1. A. Nothing. Kitchen spacing is the required distance from the inside wall of a pool.
   2. B. It is too far. Pool receptacles are required to be installed at the waterline.
   3. C. It applies only to fountains, and a pool is prohibited from having any receptacle.
   4. D. It comes from the wrong article. The pool receptacle distance is an Article 680 number. Confirm it in NEC 2026. A kitchen spacing is not that number.Keyed answer

   Article 680 locates receptacles at a pool by its own distances. Confirm the real distance in NEC 2026. Do not treat the kitchen dimension as the pool rule.

   Open NEC 2026 Article 680

9. 9 · Special occupancies and equipment · NEC Knowledge

   The hydromassage bathtub motor is supplied like a plain bathroom luminaire, with no ground-fault protection on the tub and no access left to the motor. The helper says the bathroom receptacle device covers every load in the room. What did that receptacle fail to cover?

   1. A. Nothing. A hydromassage tub is finished when any bathroom receptacle is protected.
   2. B. The hydromassage bathtub. The tub motor circuit and the access to the motor are tub rules, not a side effect of the bathroom receptacle.Keyed answer
   3. C. The pool equipotential grid of an outdoor gunite shell, which every indoor tub is required to copy.
   4. D. A classified-location seal, because a whirlpool motor is a Class I process.

   Article 680 covers the hydromassage bathtub, including ground-fault protection and access to the motor. Confirm those rules in NEC 2026. The bathroom receptacle is a different outlet.

   Open NEC 2026 Article 680

10. 10 · Special occupancies and equipment · NEC Knowledge

    The equipotential bonding conductor was sized from the equipment grounding conductor of the pump circuit. The helper says whatever ground fits the pump breaker is the bonding conductor for the whole pool. What sizing rule did the pump circuit fail to set?

    1. A. A rule that the bonding conductor must be smaller than every branch-circuit ground on the property.
    2. B. The service-neutral size, which is the required size of every pool bond.
    3. C. No rule. Equipotential bonding conductors are prohibited, so the pump ground is the only legal copper.
    4. D. The equipotential bonding conductor rule. The pump circuit's equipment ground is a different conductor and does not automatically size the bonding conductor.Keyed answer

    Article 680 sizes the equipotential bonding conductor on its own terms. Confirm that conductor in NEC 2026. Do not copy the pump circuit's equipment grounding size and call it the bond.

    Open NEC 2026 Article 680

11. 11 · Special occupancies and equipment · NEC Knowledge

    The helper left the equipotential conductor disconnected and says the pool water is conductive enough to be the bonding grid. The metal parts are not tied by a bonding conductor. What can the water not replace?

    1. A. The pump motor, which must be removed so the water can be the circuit.
    2. B. Nothing. Pool water is the required bonding conductor.
    3. C. The equipotential bonding conductor and grid. Conductive water is not the bonding system the article requires.Keyed answer
    4. D. The underground service, which is bonded by leaving the pool unbonded.

    Article 680 requires the equipotential bonding means it describes. Pool water is not that conductor. Confirm the bonding means in NEC 2026.

    Open NEC 2026 Article 680

12. 12 · Special occupancies and equipment · NEC Knowledge

    The pool water-heating equipment was left unbonded. The helper bonded the ladder and says heating equipment is a plumbing load, so it stays off the equipotential grid. The heater is part of the circulating-water system. What equipment is still on the bonding list?

    1. A. The circulating-water equipment, including this heater. A plumbing label does not remove it from the equipotential bond.Keyed answer
    2. B. No heater. Water-heating equipment is prohibited from being bonded.
    3. C. Only the bathroom exhaust fan, which is the circulating equipment the pool article means.
    4. D. The high-voltage utility lines, which must be bonded to the heater shell in place of the grid.

    Article 680 includes the electrical equipment associated with the water-circulating system in the equipotential bond. Confirm that list in NEC 2026. The ladder does not stand in for the heater.

    Open NEC 2026 Article 680

13. 13 · Special occupancies and equipment · NEC Knowledge

    The helper placed the pool switching equipment at a distance he copied from a bathroom-zone habit and says any water uses that bathroom distance. He did not check the pool-equipment distance. Which number has to be confirmed before the switch stays there?

    1. A. No number. Pool switches are required to use the bathroom distance and no other.
    2. B. The kitchen-counter spacing, which is the required distance for pool switchgear.
    3. C. The Article 680 distance for this pool equipment. The bathroom-zone distance is the wrong article. Confirm the pool number in NEC 2026. Do not install from the bathroom figure.Keyed answer
    4. D. A fuel-dispensing setback, which locates every pool panel.

    Article 680 sets where pool switching equipment may be placed. Confirm that distance in NEC 2026. A bathroom-zone habit is not the pool measurement.

    Open NEC 2026 Article 680

14. 14 · Special occupancies and equipment · NEC Knowledge

    The equipotential grid is interrupted at a coupling the helper left open. He says a single break does not matter because the rest of the wire is in the deck. The parts on the far side of the break are not bonded. What does the open coupling destroy?

    1. A. The continuity of the equipotential bond. A grid that is open is not bonding the parts past the break.Keyed answer
    2. B. Nothing. An open bonding conductor is the required way to isolate the deck.
    3. C. The service neutral, which must be opened at every pool.
    4. D. The underwater lamp voltage, which rises when the bond is continuous.

    Article 680 requires the equipotential bonding system to be continuous to the parts it includes. Confirm the continuity rules in NEC 2026. A break in the deck is not a minor spare.

    Open NEC 2026 Article 680

15. 15 · Special occupancies and equipment · Calculations

    This drill says metal parts within 5 ft horizontally of the inside wall of the pool are bonded. A ladder sits 4 ft from that wall. How many feet inside the 5 ft limit is the ladder?

    1. A. 1 ftKeyed answer
    2. B. 4 ft
    3. C. 5 ft
    4. D. 9 ft

    5 − 4 = 1 ft inside the limit, so the drill includes the ladder. Adding the two distances gives 9 ft, which is not the question. Confirm the bonding distance in NEC 2026 Article 680. The 5 ft figure is printed here so the subtraction stands alone.

    Open NEC 2026 Article 680

16. 16 · Special occupancies and equipment · Calculations

    A pool is a rectangle 20 ft by 40 ft. This drill asks for the length of a bonding conductor that follows the perimeter once, with no extra length for splices or connections. How many feet is that?

    1. A. 60 ft
    2. B. 80 ft
    3. C. 100 ft
    4. D. 120 ftKeyed answer

    The perimeter is 2 × (20 + 40) = 120 ft. Adding the two sides once, without going all the way around, gives 60 ft. Article 680 describes the equipotential bonding conductor. The length in this item is the perimeter math from the dimensions in the stem.

    Open NEC 2026 Article 680

17. 17 · Special occupancies and equipment · Calculations

    A lap pool pump full-load current is 24 A. Underwater lighting on the same equipment feeder is 12 A continuous. This drill takes both at 125%. Ground-fault protection is still required and does not change the ampacity. What feeder ampacity do you need?

    1. A. 45 AKeyed answer
    2. B. 42 A
    3. C. 36 A
    4. D. 60 A

    Pump 24 × 1.25 = 30 A. Lighting 12 × 1.25 = 15 A. Total 45 A. The 250% figure is a motor short-circuit device, not this feeder ampacity. Article 680 still requires ground-fault protection for the pool equipment. It does not replace the ampacity math.

    Open NEC 2026 Article 680

18. 18 · Special occupancies and equipment · Calculations

    Two pool pumps have full-load currents of 14 A and 8 A. An ozone generator on the same feeder is 4 A and runs more than 3 hours. Use 125% of the larger pump, 100% of the smaller pump, and 125% of the ozone generator. What feeder ampacity do you need?

    1. A. 26 A
    2. B. 30.5 AKeyed answer
    3. C. 25.5 A
    4. D. 32.5 A

    14 × 1.25 = 17.5 A. The smaller pump stays 8 A. The ozone generator is 4 × 1.25 = 5 A. Total 30.5 A. Article 680 is the pool equipment. Article 430 is the several-motor pattern this drill is using. The factors are printed in the stem.

    Open NEC 2026 Article 680

19. 19 · Special occupancies and equipment · Calculations

    A filter pump full-load current is 26 A. Conductors are 125%. The inverse-time breaker is 250% in this drill. Someone adds the two results together and calls that the wire size. What is the conductor ampacity alone?

    1. A. 65 A
    2. B. 97.5 A
    3. C. 32.5 AKeyed answer
    4. D. 26 A

    Conductors are 26 × 1.25 = 32.5 A. The breaker is 26 × 2.50 = 65 A. Adding them double-counts two different Article 430 jobs. Article 680 does not replace that split, and it still requires ground-fault protection for the pool pump.

    Open NEC 2026 Article 680

20. 20 · Special occupancies and equipment · Calculations

    A pool has 12 wet-niche luminaires at 200 W each on a 120 V circuit. Power factor is 1. The lighting is continuous, so this drill sizes the conductors at 125% of the combined current. What conductor ampacity do you need?

    1. A. 20 A
    2. B. 2.08 A
    3. C. 2400 A
    4. D. 25 AKeyed answer

    12 × 200 = 2,400 W. / 120 = 20 A. × 1.25 = 25 A. One luminaire's current is not the circuit. Article 680 covers the underwater luminaires, including the grounding rules that this ampacity step does not replace.

    Open NEC 2026 Article 680