The 2020 NEC Allows Electrical Inspectors to Periodically Inspect Swimming Pools and Similar Equipment, after Installation.
Published on January 7, 2020 by Jerry Durham
680.4 Swimming Pools, Fountains, & Similar Installations. Inspections After Installations.
The 2020 Code Making Panel has introduced a new and unprecedented Code section for this 2020 Code cycle that may prove controversial once time allows this directive to play out.
This new requirement found in Section 680.4 of the 2020 NEC allows the Authority Having Jurisdiction (AHJ) to return to a home or business for follow-up inspection(s) even after the swimming pool, fountain, or similar has passed final inspection, and the job is complete.
The Code section reads:
680.4 Inspections After Installation.
The authority having jurisdiction shall be permitted to require periodic inspection and testing.
Groundbreaking for the NEC
The idea of granting permission for electrical inspectors to return periodically, indefinitely after the electrical installation and applicable inspections are complete, is new for the National Electrical Code.
The reasoning for such radical new permission(s) is rooted in the understanding that swimming pools are liquid conductors. The water in the pool that is capable of carrying electrical current passes through one or more electric pumps; is illuminated by one or more submerged electric luminaires, and is in contact with the earth, which can periodically experience surging voltage.
Should the equipotential bonding plane surrounding the swimming pool, or the insulators separating electric pumps and electric lighting from the conductive water in the pool ever fail, the swimmers occupying the pool could be exposed to electrical hazards resulting in injury or death.
Equipotential Plane
The NEC requires an equipotential bonding plane to be assembled outside the swimming pool under the walkway surface surrounding the pool for an area measuring 3 feet outward from the swimming pool interior wall. This conductor installed under the walkway must then attach to all other conductive exposed metals measuring within 5 feet of that same interior pool wall.
The materials allowed to serve as the conductor under the walkway surface are:
- Structural reinforcing steel
- 8 AWG solid copper bare conductor encircling the pool
- Copper grid
Whatever material the electrician uses, it must connect to the swimming pool outer reinforcing shell at four equally spaced points, if that pool shell is a conductive metal material.
Bonding Within 5 feet of the Pool Wall
Once the grid or conductor material is under the walkway surrounding the pool and connected to the outer pool shell, any exposed metal within 5 feet of the surrounding interior pool wall must also be bonded to that underground conductor system by a No. 8 AWG copper conductor. This includes metal pool ladders, metal fencing, doors, window frames, and even steel conduit or cable within the first 5 feet surrounding the pool. This bonding requirement also extends to the pool electrical equipment and applicable lighting, minus any double-insulated water pump motors and pool water heaters greater than 50 amps, that have their own special bonding requirements from the manufacturer.
Deterioration of the Pool Equipotential Bonding System
The reason this elaborate equipotential system is built that connects all exposed metal surrounding the pool to the water in the pool, and to the surrounding earth is to manufacture a complete conductive path for current to flow between these components. This way, in the event of inadvertent voltage coming into contact with any single component, the voltage will ultimately energize all components. This continuity between parts reduces or even eliminates the deadly voltage gradient existing between conductive materials that can electrocute a swimmer, should swimming pool components come into contact with dangerous voltage.
Remember, it is the difference in voltage or gradient on conductive surfaces that forces electrons through the human body and causes electrocution, when inadvertent contact is made; it is not the voltage itself. Just like a bird safely perched atop an exposed street-side utility wire, a human being can safely come into contact with voltage as well, as long as that person makes no contact with a nearby surface of a different voltage.
Experts understand that deterioration can occur to the conductors, fittings, and connections that make up the equipotential bonding plane surrounding a swimming pool. With deterioration comes an increased risk of electric shock.
Physical inspection of all exposed connections and conductors, along with metered testing of continuity and resistance in Ohms along the bonded conductive parts can validate the effectiveness of an older equipotential bonding plane. It is for this reason that the NEC has included permission for the AHJ in the 2020 Code cycle to perform periodic inspecting and testing of pools and similar water-based equipment.