8.3 Pool Bonding, Underwater Luminaires & Spa Inspection Workshop (0701)
Key Takeaways
- Equipotential bonding under 680.26 equalizes potential; it is not a grounding connection and is not required to be extended to any panelboard, service equipment, or grounding electrode.
- The perimeter surface bond covers the walking surface extending 3 ft horizontally from the inside wall of the pool, installed 18 to 24 in. from the wall and 4 to 6 in. below the subgrade, with at least four connection points.
- Double-insulated pool pump motors are not required to be bonded, but 680.21 still requires a wire-type equipment grounding conductor to be run to the motor and requires GFCI protection for the outlet.
- Wet-niche luminaires must have the top of the lens at least 18 in. below the normal water level, and the forming shell conduit run must include an 8 AWG insulated copper bonding jumper to the equipotential bonding grid.
- For a non-dwelling spa or hot tub, 680.41 requires a clearly labeled emergency shutoff for the recirculation and jet pumps, located at least 5 ft from but adjacent to and within sight of the unit.
Bonding Is Not Grounding — and That Is the Whole Point
The single most valuable idea in Article 680 is that the equipotential bonding required by 680.26 and the equipment grounding required by 680.7 solve different problems.
Equipment grounding gives fault current a low-impedance path back to the source so an overcurrent device opens. It runs on a wire-type equipment grounding conductor back to the panel.
Equipotential bonding does not care about fault current at all. Its job is to make everything a swimmer can touch sit at the same voltage, so that no potential difference exists across a body in the water. A pool can be perfectly grounded and still be lethal if the water is at one potential and the wet concrete deck is at another — the swimmer bridges the difference climbing out.
That is why 680.26(B) says the equipotential bonding conductor shall not be required to be extended or attached to any remote panelboard, service equipment, or any electrode. It is a local equalizing network, not a return path. It is also why the bonding is required whether or not the pool has any electrical equipment: a pool with no lights, no heater, and no pump still needs the bonding grid, because the hazard is stray potential from anywhere.
The 680.26(B) Checklist
Work this list item by item at the rough inspection, because most of it disappears under concrete:
| Item | Requirement |
|---|---|
| Conductive pool shell | Structural reinforcing steel bonded together by steel tie wires (or the equivalent), or a copper conductor grid where the shell is not conductive |
| Perimeter surfaces | The paved or unpaved walking surface extending 3 ft horizontally from the inside wall, bonded with structural reinforcing steel or an 8 AWG solid copper conductor installed 18 to 24 in. from the inside wall, 4 to 6 in. below the subgrade, and attached to the pool reinforcing steel at a minimum of four points uniformly spaced around the perimeter |
| Metallic components | All metallic parts of the pool structure, including reinforcing metal of the shell, coping stones, and deck |
| Underwater metal forming shells | Metal forming shells and mounting brackets of no-niche luminaires |
| Metal fittings | Metal fittings within or attached to the pool structure, such as ladders, handrails, and diving-board supports — fittings smaller than 4 in. in any dimension and not penetrating the structure more than 1 in. are exempt |
| Electrical equipment | Metal parts of electrical equipment associated with the pool water circulating system, including pump motors and metal parts of equipment associated with pool covers |
| Fixed metal parts | Metal parts within 5 ft horizontally of the inside wall and within 12 ft above the maximum water level, unless separated by a permanent barrier |
| Pool water | An intentional bond of a minimum conductive surface area of 9 in.² in contact with the pool water — usually a listed corrosion-resistant fitting or the metal ladder |
The conductor is 8 AWG solid copper, insulated, covered, or bare, and aluminum is not permitted. Connections must be made by exothermic welding or by listed pressure connectors or clamps of brass, copper, copper alloy, or stainless steel.
Exception for double-insulated pump motors: where a listed double-insulated pool pump motor is installed, the motor itself is not bonded to the equipotential grid, and the 8 AWG conductor is instead brought to the motor location and left accessible for a future replacement motor. But the motor still requires a wire-type equipment grounding conductor and the outlet still requires GFCI protection — the double insulation excuses the bonding, not the grounding.
Underwater Luminaires — 680.23
| Requirement | Rule |
|---|---|
| Lens depth | The top of a wet-niche luminaire lens must be at least 18 in. below the normal water level |
| Transformer / power supply | Must be listed for the purpose, with an isolated secondary winding and a grounded metal barrier between the primary and secondary |
| GFCI | Required for luminaires operating above the low-voltage contact limit; a luminaire supplied at or below that limit from a listed transformer or power supply does not require GFCI |
| Forming shell | Listed; of brass or other approved corrosion-resistant metal, or listed nonmetallic; bonded and grounded |
| Conduit to the forming shell | Brass, other approved corrosion-resistant metal, or listed nonmetallic conduit; where nonmetallic conduit is used, an 8 AWG insulated copper bonding jumper must be installed in the conduit from the forming shell to the junction box, terminated with a listed connector |
| Cord and flexible cord | The flexible cord of a wet-niche luminaire must include an insulated copper equipment grounding conductor not smaller than 16 AWG, and the cord must be long enough to allow the luminaire to be raised onto the deck for relamping |
| Servicing | The luminaire must be removable from the water for inspection and relamping without lowering the water level |
The junction box serving a wet-niche luminaire must be a listed swimming-pool junction box with threaded entries or hubs, of copper, brass, suitable plastic, or other approved corrosion-resistant material, located not less than 4 in. above ground level or the pool deck, not less than 8 in. above the maximum pool water level, and not less than 4 ft from the inside wall of the pool unless separated from it by a solid fence, wall, or other permanent barrier.
Why the lens depth matters. An 18 in. submersion keeps the lens below the level where a swimmer floating at the surface would contact it, so a cracked lens does not put a person directly across the luminaire.
Commercial Spas and Hot Tubs — Article 680 Part IV
On a hotel, health club, or apartment amenity deck, the E2 inspector's spa checklist is short and specific:
- 680.41 Emergency shutoff. For other than one-family dwellings, a clearly labeled emergency shutoff or control switch for the purpose of stopping the motor(s) that provide power to the recirculation system and jet system must be installed at a point readily accessible to the users, at least 5 ft away from but adjacent to and within sight of the spa or hot tub. This is a life-safety rule about hair and limb entrapment in a suction fitting, and it is the item most often missing on a commercial installation.
- 680.42 Outdoor installations. An outdoor spa or hot tub follows Part II unless the relaxations of 680.42 apply — most importantly, a listed self-contained unit or a listed packaged assembly marked to indicate integral protection may use flexible connections and cord-and-plug connection under the stated conditions.
- 680.43 Indoor installations. Indoor units require at least one 125 V, 15 or 20 A receptacle located not less than 6 ft and not more than 10 ft from the inside wall, and all 125 V through 250 V, 15 and 20 A receptacles within 20 ft must be GFCI-protected. Luminaires, lighting outlets, and ceiling fans over the unit and within 5 ft of the inside walls have specific height and GFCI requirements.
- 680.44 GFCI. The outlet supplying a self-contained spa or hot tub, a packaged equipment assembly, or a field-assembled unit must be GFCI-protected, with narrow exceptions for listed units rated over 250 V or supplied by other than a single-phase 125/250 V source.
- Bonding. The metal parts listed in 680.42(B) and 680.43(D) must be bonded with an 8 AWG solid copper conductor, with the same double-insulated-motor allowance that applies to pools.
Rough-inspection reality. Almost everything in 680.26 is buried in concrete by the time anyone thinks about it. If you inspect one thing on a pool rough, inspect the perimeter surface bond and its four connection points — it is the item most often skipped and the one that cannot be corrected afterward without demolition.
Which statement about the equipotential bonding required by 680.26 is correct?
A listed double-insulated pool pump motor is installed. What does Article 680 require?
A hotel installs an indoor spa in a fitness area. What does 680.41 require that would not apply at a one-family dwelling?