By Marcelle Dibrell
A recently published electrical safety study claiming that a single copper wire can provide effective bonding is being challenged by safety experts.
On June 20, 2025, the Pool Industry Council — a subcommittee of the Florida Swimming Pool Association — released a report stating that proper equipotential bonding, critical for preventing shocks and electrocutions, can be achieved with a properly installed #8 AWG copper wire loop.
Equipoten t i al bonding in swimming pools involves physically connecting all metal parts within and around the pool (e.g., ladders, handrails, pool equipment) to create an electrically safe environment by eliminating any significant voltage differences between these parts, reducing the risk of electric shock. In essence, it's about making sure everything in and around the pool is at the same electrical potential.
Entitled “Field Validation of Equipotential Bonding Systems for Permanent In-ground Swimming Pools,” the Pool Industry Council, PIC, commissioned SunSmart Engineering to conduct the study.
“We are very happy with the
https://www.cpsc.gov/Recalls/2025/Bestway-Intex-and-Polygroup-Recall-Certain-Above-Ground-Pools-48-Inches-and-Taller-Due-to-Drowning-Hazard-Nine-Deaths-Reported-Five-Million-Pools-Sold-Since-2002
Equipotential bonding grid forms an equipotential bonding plane in and around the pool area. This bonding plane can be achieved with one “alternative means” bonding jumper (left) or multiple bonding jumpers (right). Equipotential bonding has been required in the state of Florida since 2005, when the National Electrical Code introduced the term to replace the earlier “common bonding grid” requirement. Photo credit: National Electric Code. study,” said PIC Vice Chair Adam Alstott. “This is the most thorough study of swimming pool equipotential bonding methods to date, and we are happy that we can share these results with the industry and public. Our goal with this study is to help the swimming pool and spa industry better understand equipotential bonding through a scientific and data-based approach. This study does that.”
But not everyone agrees. “Conclusive research from the last two decades proves definitively that the single wire does NOT protect the public alone, even when installed correctly,” said Reuben Clark, president of Consolidated Manufacturing.
Clark added “If someone is still asking for more tests, the only logical conclusion is that they are trying to invent a different/false outcome. That indeed seems to be what happened with this PIC report.”
And because the PIC report could help guide electrical standards, Clark and other electrical experts are concerned that the pool industry will embrace the single copper wire as a means of achieving effective equipotential bonding.
That’s because the Electric Power Research Institute (EPRI), the Institute of Electrical and Electronics Engineers (IEEE), and the Consumer Product Safety Commission (CPSC) have highlighted cases of pool electrocutions, primarily due to improper bonding of metallic parts and lighting fixtures.
And the key point of contention has been whether a single No. 8 solid copper wire around the pool's perimeter is sufficient, or if a more extensive copper wire mesh grid is necessary, especially for pools without traditional concrete/rebar decks.
Matt Norwalk, chair of the IEEE Stray and Contact Working Group, said that he thoroughly reviewed the PIC report and has found problems and inconsistencies with the study’s methods.
“It cannot be stated that this test was performed to IEEE and EPRI standards,” Norwalk said. “The authors' assertion that this study is ‘the most thorough and comprehensive study to date’ is simply incorrect and ignores the vast amount of research performed by EPRI and members of the IEEE Stray and Contact Voltage Working Group. Investigations have been performed across the United States and in many areas of Florida and have consistently found the single wire deck bonding method to be insufficient at creating an equipotential bond of these surfaces.”
The issue is a matter of life or death, as it concerns the electrical safety of swimming pools and common construction techniques that guard against electrocution hazards.
Consider the following scenario: A person is in a swimming pool with their arm(s) resting on the deck. An electrical fault occurs in or around the pool, electrifying the area. If there is a difference in the electrical potential between the water and the deck, the person will become a conductive path and experience a shock, that could be dangerous or even fatal, depending on the magnitude of the current that travels through the person. If there is no electrical potential difference between the water, the person, and the deck, the person will experience nothing at all despite the electrical fault.
That is the purpose of bonding: to eliminate or reduce potential voltage differences between pool areas. That way, even if some kind of electrical fault occurs, swimmers will be unharmed, because everything nearby is at the same voltage potential. (Current requires a voltage difference to travel.)
According to the study’s authors: “Equipotential bonding minimizes voltage gradients between conductive parts and surfaces within and around pool environments. This measure reduces shock hazard potential due to stray or fault currents. Bonding all conductive parts ensures voltage differences stay within tolerable limits for human safety.”
But there is a difference of opinion as to which methods can adequately accomplish this.
In short, when a fault occurs at a swimming pool, what safety provisions should be in place to eliminate or reduce voltage differences between human contact points?
For swimming pools, the choice generally comes down to two basic options: a single wire loop or a bonding grid.
Bonding accomplished by a single wire loop involves installing a single, continuous copper wire (typically #8 AWG) around the perimeter of the pool, connecting all metallic parts. It's simple and generally considered cost-effective.
A bonding grid, on the other hand, involves installing a network of copper wires or rebar, arranged in a grid pattern, usually installed under or within the perimeter surface. This provides a more comprehensive, evenly distributed bonding plane.
The debate centers on whether one of these methods is superior to the other.
The Pool Industry Council’s June 2025 report claims to resolve the question, stating that both provide adequate levels of protection.
“Both bonding methods — #8 AWG copper wire loop and the copper bonding grid — can provide effective equipotential bonding when properly installed,” the study concludes.
Within the pool and spa industry, both an equipotential bonding grid and a single copper wire (a #8 AWG copper wire loop) have long been used and recommended by the National Electrical Code (NEC), to guard against voltage gradients and the potential for electrical shock or electrocution.
But many have questioned whether a single copper wire is sufficient to prevent voltage differences caused by a fault within a pool’s electrical system. And in 2023, the option for the single copper wire was actually removed from the NEC.
With the Tentative Interim Amendment re-writing of the 2023 NEC 680.26(B)(2), the single copper wire was eliminated from the code as a safety precaution for bonding beneath decks, replaced with the bonding grid. (A Tentative Interim Amendment is an enforceable change to the NEC which is issued to address urgent safety concerns when it’s too late for normal code revisions.)
Clark said the decision to remove the single copper wire from the NEC was prompted by real-world electrical incidents.
“Occurrences are happening in the field,” Clark said.
In 2022, there were a series of severe shocking incidents at newly constructed swimming pools that had been built to code, which then allowed the single copper wire.
The homeowners involved hired an attorney to determine who had allowed such an unsafe code to be adopted.
According to Clark, that was what prompted revaluating the code, ultimately resulting in the Tentative Interim Amendment.
Clark said that in response to potential legal action, leaders at the NEC appointed a balanced panel of the world’s leading experts to determine if the single copper wire should be removed as an option from the National Electric Code (NEC).
Before looking at the research, that panel was split on the decision. But after studying years of documentation from real-world swimming pools, the panel became convinced that the single copper wire was unsafe, and they voted unanimously to change the NEC. The panel swiftly drafted and issued the Tentative Interim Amendment — which removed the single copper wire from the code, effective immediately.
Whereas the 2023 NEC allowed a “copper ring” constructed from a 8 AWG bare solid conductor for perimeter bonding, the TIA deleted reference to the “ring” and currently specifies that “one minimum 8 AWG bare solid copper conductor” can be used only in unpaved portions of the perimeter AND “Be installed only in perimeter surfaces not intended to have direct access to swimmers in the pool.”
“The single wire was definitively proven unsafe by multiple sources and events,” Clark said.
Nonetheless, there remains pushback against the requirements for bonding grids. Single wire proponents continue to argue that a properly installed single wire bond, provides adequate protection, and the added cost of a grid is unnecessary. Grids are generally more expensive and labor-intensive to install than single wire loops, leading to a debate about the cost-benefit ratio.
Clark, however, argues that achieving what he believes is proper equipotential bonding — by adhering to the three options allowed within the amended 2023 NEC — adds an incremental cost of between $300 and $500.
And that disagreement is why the Pool Industry Council commissioned a two-month study examining the performance of the wellknown methods of implementing equipotential bonding in and around swimming pools.
The specifics of the study, which took place from April 7 – June 12, 2025, are as follows: Utilizing nine residential swimming pools in Central Florida, three were bonded with an #8 AWG single bonding loop, three with copper reinforcement grids, and three on conductive pools with inline water bond plates and #8 AWG single wire loop. Using voltage performance threshold of 1.0 Volts Alternating Current across a 500ohm load, the studied compared the bonding methods by testing bonding continuity and voltage gradient assessments.
The authors concluded that both the grid and the lone wire produced safe voltage levels.
Confronted with Clark and Norwalk’s opposing arguments, the FSPA, which helped sponsor the study, insists that the test methods were appropriate and their results were thorough.
“The test method used in the report was taken verbatim from EPRI's website (https://strayvoltage.epri. com/general/testresults.aspx),” said Dallas Thiesen, FSPA’s Chief of Government Relations Officer. “The study by SunSmart Engineering, is in fact the most thorough examination of this issue to date. All of the pools used were newly built, to code, in real world conditions with no prior complaints of shock or bonding failure, and the bonding was confirmed intact and operational before fault induction and testing was conducted. Other tests or examinations of this topic cannot claim that level of research control.”
John Antonelli, SunSmart’s Vice President of Engineering, indicated that investigations into prior electrical incidents have not demonstrated that inadequate bonding was the culprit.
“We could not find any definitive evidence when investigating known stray voltage incidents that clearly indicated that the presence, or type, of perimeter bonding would have mitigated or eliminated the voltage present in the pool and/or surrounding area,” Antonelli said.
“The descriptions and data available are shallow and do not delve deeply enough into incidents to pinpoint the perimeter bonding (or lack thereof) as the deciding factor that would have protect swimmers from stray voltage. We have heard this claim made, however, and would welcome thorough, unbiased reporting into exactly what caused any known incidents and what could have been done to prevent them. Perimeter bonding is not necessarily a magical cure-all for shoddy electrical equipment and poor workmanship.”
Experts are aware that their recommendations regarding equipotential bonding can have lifeor-death consequences. https://fspa.com/wp-content/uploads/2025/07/Equipot-Bond-Report-FINAL_2025.06.pdf Click here to read the full PIC study report and click
www.floridapoolshock.com to http://www.floridapoolshock.com
see real-world field testing of equipotential bonding.
Reuben Clark is the President and cofounder of Consolidated Manufacturing International, LLC, an electrical products manufacturer for the pool industry.
Mr. Clark holds an MBA, is a member of the IAEA, NCEIA, and NFPA, and has been involved in development of the National Electric Code..
NEC 680.26 establishes the requirements for equipotential bonding in and around permanently installed swimming pools. Its primary purpose is to minimize voltage gradients that could occur between conductive parts (e.g., pool water, decks, metal objects, electrical equipment) during a fault or leakage event. By electrically interconnecting all metallic and conductive components using a copper bonding conductor or approved methods, the code aims to prevent hazardous shock conditions and ensure safe touch and step potentials for pool users. Photo credit: UpCodes
