For decades, the National Electrical Code (NEC) prohibited underground wiring to be located under a pool and wiring for lighting fixtures in the zone that extends 5-feet horizontally from the inside wall of a pool. The exception was always to allow wiring in that location if it supplies electrical equipment incidental to the pool, such as an underwater light fixture. Now, everything has changed. With the adoption of the 2014 NEC comes a change that allows certain light fixtures to be installed around the water's edge—outside of the pool if installed a certain way. That's correct; these luminaires may be located where one can just reach out and touch them. The applicable code is Section 680.22(B)(6) in the 2014 NEC, and these low-voltage lights can be located within arm's reach. Below, I briefly discuss each requirement and then discuss the possible benefits and pitfalls of this new Code article from my point of view.
One requirement is that the special luminaires be supplied by listed transformers or power supplies that comply with 680.23(A)(2). These transformers must be listed for swimming pool and spa use. The transformer or power supply must incorporate either a transformer of the isolated winding type, "with an ungrounded secondary that has a grounded metal barrier between the primary and secondary windings, or one that incorporates an approved system of double insulation between the primary and secondary windings." This is an easy requirement to comply with since these transformers are widely available on the market today.
A second requirement for the luminaire to be allowed in this location is that it not require grounding. This requirement also seems simple enough. But I discuss how this can pose a problem later.
A third requirement for the luminaire to be allowed in this location is that it not exceed the voltage as specified in the "low-voltage contact limit." The low-voltage contact limit can be found in Section 680.2, Definitions. It is defined as voltage which does not exceed the following values:
• 15 volts (V) RMS for sinusoidal alternating current (AC)
• 21.2V peak for nonsinusoidal AC
• 30V for continuous DC
• 12.4V peak for DC that is interrupted at a rate of 10 to 200 hertz
Don't let the title of the definition for low-voltage contact limit fool you. This does not necessarily mean that it is safe for an individual to come into contact with voltage falling within the limitations described therein. In fact, these contact limits can be dangerous for people who have implanted cardioverter defibrillators (heart devices). Implanted cardioverter defibrillators continuously monitor and control a patient's heart rhythm. In two recently documented cases, people with defibrillators experienced device misreadings while in a private family or hotel pool. In another two cases, people experienced unwarranted shocks from their defibrillators while in public pools.
Furthermore, any external interference with an implanted heart device can be serious. If this happens to a pacemaker, it usually reverts to constant pacing mode. A defibrillator could (in theory) send a shock when one was not needed or possibly be inhibited from providing a shock when one is needed. People may say that there is no proof that this will happen. But conversely, there is no proof that it will not. Was this factor taken into account when introducing voltages around swimming pools?
The final requirement for the light to be allowed in this location is that the luminaire be properly listed. This sounds simple enough, but at present, I do not know of a low-voltage luminaire that does not require grounding and is listed to be within 10 feet of a pool. It is important to point out that, for low-voltage landscape lighting, secondary circuits are not permitted to be grounded (Section 411.6). But all of the listed, low-voltage fixtures that I can find have installation instructions that state, “Do not install within 10 feet (3 m) of pools, spas, or fountains.” I have searched through the numerous low-voltage luminaires on the market today, but I am unable to find one that is specifically listed to be above ground and next to a pool. Does such a luminaire exist?
Putting all four pieces together, one is left with a Code change for a lighting system that may not have been invented yet, and the problem lies herein. In my opinion, this change is in conflict with the logic behind Section 680.10. This additional wiring simply does not need to be near the pool, even though I do agree that the lights may look pretty in the landscaped area. To reiterate, for decades, Article 680 has gone to great lengths to eliminate voltage gradients around the pool area. Eliminating voltages around the pool is the entire reason that pool bonding was created, and the reason we go to such great lengths to achieve a Code-compliant swimming pool bonding grid. Introducing additional wiring around a pool can at some point lead to unforeseen circumstances. The wiring may fray, deteriorate or succumb to loose connections over time. While this may be true for all wiring or wiring methods, the area surrounding the pool can often be subject to physical damage from shovels (digging, landscaping), weed-whackers, and other gardening tools. Will at least Schedule 40 PVC be used as the wiring method to withstand any possible physical damage?
In theory, we can now have a person in a properly bonded swimming pool at a given potential. For our purposes, assume that the person in the pool is at 3V. The person is at the same voltage as the handrails, water, deck, diving board, ladder, etc. There is no shock because the person is at the same potential as all metal parts (the bonding grid). Now assume that he or she reaches out and comes into contact with the voltage source for this new-type luminaire. Remember the grounding requirement—the luminaire must not require grounding. So, if wiring were to become exposed or some other mishap were to occur, it is now possible to have a transfer of voltage, and the person can get a shock. It is logical to conclude that the potential for an accident has increased. I’ve already heard the argument, “If you can have a light inside the pool, you should be able to have a light outside the pool.” However the luminaire next to the pool is not the same as the underwater luminaire. The underwater luminaire is grounded, and the light niche is bonded.
I would not be surprised if some interpret this Code to mean that any listed low-voltage fixture can be used as long as it is used in conjunction with a transformer that complies with 680.23(A)(2). I do not feel that this would comply. Incorrectly using the ordinary "malibu-style" low-voltage fixture commonly sold in a local home center could prove to be hazardous in this instance. These luminaires use "quick-connect" type wiring that could very well leave an exposed voltage source. Also, low-voltage landscape lighting systems are required to be listed; NEC 110.3(B) mandates that the product shall be installed and used in accordance with any instructions included in the listing or labeling. As previously mentioned, all of the listed, low-voltage fixtures that I can find have installation instructions that state, “Do not install within 10-feet (3 m) of pools, spas, or fountains.” I'm not convinced that taking components from different systems and putting them together in a way that they were never intended to be used is a good thing. And I don’t even want to think about the implications that this new code may have for work done without a permit. As we all know, most jobs go uninspected; permits do not always get pulled.
When it comes to wiring near a swimming pool, if I err, let it be on side of safety. I think that Section 680.22(B)(6) of the 2014 NEC should be stricken as a matter of practical public safety, especially taking into consideration the hazards this may pose to people who have implanted heart devices. All things considered, I feel that this new change makes the Code less safe. Even the layperson is aware of this simple truth—water and electricity do not mix. We should always strive to keep voltage sources away from the water’s edge whenever possible. And no matter what, always be absolutely certain that the swimming pool is properly bonded as outlined in Article 680.26.
If anyone knows of a system listed, low-voltage light that can be outside the pool at the water’s edge, please drop me a line or email.