Electric shock drowning (ESD)
happens when marina or onboard electrical systems leak electric current into the water. The current then passes through the body, causing paralysis, and results in drowning. During the summer, NFPA is reminding people about the potential electrical hazards that exist in swimming pools, hot tubs and spas, on board boats and in the waters surrounding boats, marinas and launch ramps.
Swimming pools, hot tubs, and spas
Summer is the time of year to have swimming pool equipment, hot tubs, and spas inspected and then properly maintained to make sure that life-saving measures such as ground-fault circuit interrupter (GFCI) protection and all grounding and bonding systems are functioning properly. Tips for swimmers:
- Look out for underwater lights that are not working properly, flicker, or work intermittently.
- If a tingling sensation occurs while swimming, immediately stop swimming in your current direction. Try to swim in a direction where you had not felt the tingling, exit the water as quickly as possible, and avoid using metal ladders or rails. Touching metal may increase the risk of shock.
- Do not swim before, during, or after thunderstorms.
Tips for swimming pool owners
- Have a qualified electrician periodically inspect and—where necessary—replace or upgrade the electrical devices or equipment that keep your pool, spa, or hot tub electrically safe. Have them show you how to turn off all power in case of an emergency.
- Make sure that any overhead power lines maintain the proper distance over a pool and other structures, such as a diving board. If you have any doubts, contact a qualified electrician or your local utility company to make sure power lines are a safe distance away.
- If you are putting in a new pool, hot tub, or spa, be sure the wiring is performed by an electrician experienced in the special safety requirements for these types of installations.
- Electrical appliances, equipment, and cords should be kept at least 6 feet away from the water. When possible, use battery-operated instead of cord-connected appliances and equipment, such as televisions, radios, and stereos.
ESD and the National Electrical Code
Marinas:
- Part III of Article 555 covers electrical installation requirements for floating buildings.
- 555.10 covers the requirements for permanent signs at docking facilities, boatyards, and marinas.
- 555.13 – All metal parts in contact with the water, all metal piping, and all non-current-carrying metal parts that are likely to become energized and that are not connected to a branch circuit or feeder equipment grounding conductor shall be connected to the grounding bus in the panelboard. Connections to bonded parts shall be made in accordance with 250.8. using solid copper conductors; insulated, covered, or bare; not smaller than 8 AWG.
- 555.5 – Pier power distribution systems maximum voltage is 250 volts maximum phase to phase. Pier power distribution systems, where qualified personnel service the equipment under engineering supervision, are permitted to exceed 250 volts but shall not exceed 600 volts.
- 555.7 – Transformers and enclosures shall be identified for wet locations, for both new installations and replacement of existing transformers.
- 555.15 is a new section addressing modification or replacement of electrical enclosures, devices, or wiring methods necessary on a docking facility to comply with the requirements of the NEC and have the circuit inspected. Existing damaged equipment shall be identified, documented, and repaired by a qualified person to the requirements of the NEC it was originally installed under.
- 555.30(B) – Replacement electrical connections must be installed at least 12 inches above the deck of a floating pier.
Swimming pools, hot tubs, and spas:
- 680.7(C) – Terminals used for bonding and equipment grounding must be identified for use in wet and corrosive environments. Field-installed terminals in damp or wet or corrosive environments shall be composed of copper, copper alloy, or stainless steel and shall be listed for direct burial.
- 680.9 – The requirements for overhead power now apply to all conductors and not just overhead service conductors.
- 680.12 – Pool equipment rooms require at least one GFCI-protected receptacle on a 125-volt, 15- or 20-amp circuit. Any other receptacles installed in the equipment room must be GFCI-protected as well.
- 680.21(C) – All outlets serving swimming pool motors are required to have GFCI protection for personnel. This applies to replacement pump motors as well.
- 680.22 – Electrical equipment other than receptacles and lighting must be a minimum of five feet away from the swimming pool unless separated by a barrier.
- 680.23(B)(2)(a) – Conduits leading directly to the forming shell of underwater luminaires shall be required to be listed as red brass or stainless steel.
- 680.26 –Equipotential bonding has seen some significant changes in the 2023 NEC around performance and perimeter surfaces.
- 680.43(B)(2) takes you to 680.23(B)(6) for wet-niche luminaires installed in the foot well of a spa are only required to reach the bench area when removed for maintenance.
With all this GFCI protection required for electrical equipment associated with swimming pools, the chances of being shocked or electrocuted in a swimming pool have been reduced dramatically. However, GFCI devices require testing and maintenance according to the manufacturer’s instructions. Following the recommended testing and maintenance schedule ensures that the GFCI protection functions when needed.
Frequently Asked Questions
What is electric shock drowning (ESD)? ESD results from the passage of typically low-level electrical current through a swimmer’s body. The current interferes with the body’s nervous system and can cause temporary paralysis, leading to the individual being unable to stay afloat and eventually drowning.
How common is ESD? It is not known exactly how many cases of ESD occur annually in the United States or elsewhere. In investigations of swimming deaths, it is sometimes difficult to determine if ESD was to blame since the actual cause of death is drowning. Because of this, many cases of ESD have probably gone undocumented.
Does ESD only occur at marinas? Electric shock drowning is not limited to marinas. The majority of ESD incidents have occurred at residential waterfront locations with private docks utilizing energized electrical wiring.
What are the warning signs of areas where ESD may occur? The general public will not see the potential hazard with their eyes. An electrical system failure typically occurs over time. That means an individual could swim or otherwise be in a body of water for years, months, weeks, or days and not be exposed to the hazard. Yet that same body of water can be deadly if the electrical insulation on an energized conductor fails and energizes metal portions of a boat.
What causes electrical current to leak into the water? The marina environment is very harsh for electrical equipment. Boats are also exposed to harsh conditions while in use. These harsh conditions can cause electrical equipment to fail, introducing the potential for electrical current to enter the water. It is also important to understand that many variables impact current flow and that no two bodies of water are the same. In marinas, boats come and go. A safe boat in a transient slip may be replaced by an unsafe boat. Some percentage of ESD occurs where no boats are involved. In those instances, the fixed installation is the cause.
How can you know if somebody is affected by ESD? If we wait until the signs of an electric shock drowning are evident, it will likely be too late; that’s why NFPA is educating people about not swimming around boats, docks, or marinas. The hazard is greatest near the source (the dock or the boat). If a swimmer starts to feel a tingling sensation, they should immediately start swimming in the direction from which they came, which should cause that sensation to lessen, and exit the water as quickly as possible. If they’re able, they should also avoid using metal ladders or rails to exit the water, since touching metal may increase the risk of shock.
Why does freshwater cause more issues with ESD than saltwater? Freshwater is less conductive than saltwater. A human body in freshwater is a more conductive path for electrical current to flow than the water is, so it is more likely that current will flow through the body. Because saltwater is more conductive, the current is more dispersed and is less likely to concentrate in the body.
What should individual boat owners do to help people or themselves avoid ESD? Avoid entering the water when launching or loading a boat. These areas can contain stray electrical currents in the water, possibly leading to electric shock drowning or injury from shock, including death. Each year, have the boat’s electrical system inspected by a qualified marine electrician to be sure it meets the required codes of your area, including those set by the American Boat & Yacht Council. Make the necessary repairs, if recommended. Follow the same steps after any major storm that affects the boat. Check with the marina owner about the marina’s electrical system and whether it has recently been inspected to meet the required codes of your area, including NFPA 70, National Electrical Code (NEC). Have ground fault circuit protection (GFCI and GFPE) installed on circuits supplying the boat; use only portable GFCIs or shore power cords (including “Y” adapters) that bear the proper listing mark for marine applications when using electricity near water. Test GFCIs monthly. Never modify the electrical system on a boat or shore power to make something work. The code-required safety mechanisms in place are intended to alert people if something is wrong with the boat and with shore power. Find a licensed, qualified professional to help determine the cause of the problem.
How much do ground-fault protection of equipment (GFPE) and ground-fault circuit interrupters (GCFIs) help protect against ESD? GFPE and GFCIs add significant value. Keep in mind, the environment is harsh and equipment must be maintained to continue providing protection. GFPE and GFCI protection alone does not solve the problem. Ongoing maintenance is essential. Using the latest editions of the NEC, NFPA 302, Fire Protection Standard for Pleasure and Commercial Motor Craft, and NFPA 303, Fire Protection Standard for Marinas and Boatyards, are also essential.
How much of a problem is ESD at home (pools, hot tubs, etc.) versus out at a dock or near a boat? Or is that unknown? Is it the same? We likely do not have scientifically based evidence to answer this question. We would speculate that hazards in water are evenly distributed.
What should pool owners do to help avoid ESD? When putting in a new pool or hot tub, be sure the wiring is performed by an electrician experienced in the special safety requirements for these types of installations. Have a qualified electrician periodically inspect and—where necessary—replace or upgrade the electrical devices or equipment that keep a pool, spa, or hot tub electrically safe. Have the electrician show you how to turn off all power in case of an emergency.
Look out for underwater lights that are not working properly, flicker, or work intermittently.
What does the NEC require for marinas? The NEC, in Article 555, requires marinas to have signs posted warning against swimming due to potential shock hazards from electrical currents that may be present in the water. NFPA further encourages marina management to communicate this to boat owners and the public through newsletters, etc.
What else can marina ownership do to help? Marina owners should have their equipment inspected or tested by a qualified marine electrician on a regular basis. Many marinas will not allow a transient boat to dock until the boat has been tested for electrical hazards with a listed leakage current measurement device.
OSHA’s Top 10 Violations
No. 1 Violation: Fall Protection
Fall Protection once again retains its number one position on this important list. These violations are associated with the Fall Protection rules of OSHA 1926.501, which sets forth requirements for employers to provide fall protection systems for its employees.
There were a total of 6,143 violations issued in this category.
No. 2 Violation: Hazard Communication
Hazard Communication remained in the number two position. The purpose of this group of rules is to ensure the hazards of all chemicals produced or imported are classified — and that information concerning the classified hazards is properly transmitted to employers and employees. The requirements of 1910.1200 are consistent with the provisions of the United Nations Globally Harmonized System of Classification and Labeling of Chemicals (GHS), Revision 3.
There were a total of 5,161 violations issued in this category.
No. 3 Violation: Scaffolding
Violations related to Scaffolding use are still widespread across many industries. It’s important to note that the rules of 1926.451 do not apply to aerial lifts, the criteria for which are set out exclusively in 1926.453.
There were a total of 4,029 violations issued in this category.
No. 4 Violation: Respiratory Protection
The rules of 1910.134, which focus on Respiratory Protection, applies to General Industry (part 1910), Shipyards (part 1915), Marine Terminals (part 1917), Longshoring (part 1918), and Construction (part 1926). Violations associated with respiratory protection requirements apply to many different trades in the construction industry as well as plant/facility workers.
Overall, there were 3,223 violations issued in this category.
No. 5 Violation: Lockout/Tagout
This was the biggest mover on this year’s list. It jumped up three positions from the 2013 ranking. Lockout/Tagout rules are vitally important for many different types of employees. Standard 1910.147 establishes minimum performance requirements for the control of such hazardous energy. This standard covers the servicing and maintenance of machines and equipment in which the unexpected energization or startup of the machines or equipment — or release of stored energy — could harm employees.
There were a total of 2,704 violations issued in this category.
No. 6 Violation: Powered Industrial Trucks
Although violations associated with Powered Industrial Trucks don’t often come to mind when thinking about electrical work, OSHA issues a lot of citations in this area. Section 1910.178 contains safety requirements relating to fire protection, design, maintenance, and use of fork trucks, tractors, platform lift trucks, motorized hand trucks, and other specialized industrial trucks powered by electric motors or internal combustion engines.
There were a total of 2,662 violations issued in this category.
No. 7 Violation: Electrical Wiring Methods
The good news here is that this “electrically focused” category dropped down two positions on this year’s listing. Section 1910.305 focuses on Electrical Wiring Methods, components, and equipment for general use. It does not, however, apply to conductors that are an integral part of factory-assembled equipment.
There were a total of 2,490 violations issued in this category.
No. 8 Violation: Ladders
Section 1926.1053 applies to all Ladders, including job-made ladders. These rules apply to many different plants/facilities as well as all types of construction sites.
There were a total of 2,448 violations issued in this category.
No. 9 Violation: Machine Guarding
As noted in 1910.212, one or more methods of Machine Guarding shall be provided to protect the operator and other employees in the machine area from hazards such as those created by point of operation, ingoing nip points, rotating parts, flying chips and sparks. Examples of guarding methods include barrier guards, two-hand tripping devices, and electronic safety devices.
There were a total of 2,200 violations issued in this category.
No. 10 Violation: General Electrical Requirements
In another bit of good news on the electrical front, violations related to General Electrical Requirements dropped down one position from last year’s list to round out the top ten listing. 1910.303 focuses on the proper installation and use of electrical conductors and equipment.
There were a total of 2,056 violations issued in this category.
In a first, a man receives a whole eye transplant after surviving high-voltage electric shock
The eye transplant, which was combined with a partial face transplant, did not restore vision. Experts still say it is a groundbreaking achievement. Surgeons at NYU Langone Health have completed the world’s first whole eye transplant, a groundbreaking advancement many thought was impossible. The patient, Aaron James, 46, a military veteran from Hot Spring Village, Arkansas, cannot see out of the transplanted eye, but he considers the operation a success nonetheless. “You’ve got to start somewhere, and hopefully this will get the ball rolling on future surgeries,” James said in an interview.
Aaron James before his accident.Courtesy James family
In 2021, James survived what should have been a fatal electric shock while he was working as a high-voltage lineman. His face accidentally touched a live wire, causing devastating injuries, including the loss of his left eye, his nose and his lips. Only bone was left in his left cheek and his chin. Much of his left arm was also stripped to the bone.
The operation, which took place in May, lasted 21 hours and required the expertise of more than 140 surgeons, nurses and other health care professionals. In addition to the eye transplant, James also received a partial face transplant, which remains an incredibly rare procedure, with fewer than 50 face transplants having been performed worldwide since the first one in 2005. The donated face and eye came from a single donor. The eye had never been removed from the donor’s socket, and the surrounding tissue and the optical nerve remained intact.
Still, transplanting the new eye was laborious. Blood vessels surrounding the eye are extremely small, making it a challenge to attach enough for adequate blood flow. Reattaching the optic nerve is another challenge. As part of the operation, the surgeons also injected adult stem cells into James’ optic nerve — another first — to prompt the nerve to create healthy new cells. Five months after James’ surgery, there is healthy blood flow to the retina, the part of the back of the eye that converts light into the electric signals the brain converts into images — a major sign of vitality.
Aaron James after the face and whole eye transplant.NYU Langone Health
“Although there is no sight, we’ve crossed a barrier that many didn’t think was possible,” said Dr. Eduardo Rodriguez, the director of the Face Transplant Program at NYU Langone in New York City, who led the surgery. “Nothing like this has ever been attempted. There isn’t even any science published in the literature that could indicate what could be the result of such a transplant.”
The eye also has normal pressure, and it is not painful. Infection around the brain was another major complication James was able to avoid in the crucial months after the transplant. His body did not reject the transplant, a significant achievement — some experts believe the eye has a different immune system from the skin, so it could have been rejected. “That is an absolutely remarkable accomplishment in itself,” said Dr. Joseph Rizzo, the director of the neuro-ophthalmology service at Mass Eye and Ear at Mass General Brigham and a professor of ophthalmology at Harvard Medical School in Boston.
More than sight
Rizzo said he believes a whole eye transplant that restores vision is still “beyond our capabilities at the moment.” “For one to have sight at the level you’d be able to do something functional, it would require the reconnection of a fair number of nerve cells,” he said. “But the complexity is not just whether some nerve cells can regrow.” Roughly 1.2 million nerve fibers connect each eye to the brain, and those nerves are not connected in a random fashion. “Point A has to connect to point A,” Rizzo said. During brain development, a complex system of interactions forms specific pathways that connect points on the retina to points on the brain, he said. The adult brain does not have these same systems, at least not in a robust way. “The public should not be imagining that vision will be restored at this point, but from a scientific standpoint, even if they were able to get a small number of nerve cells to grow back to the brain, that would be a groundbreaking accomplishment,” Rizzo said, noting that full vision restoration, if ever possible, is still likely to be a long way from reality.
Rodriguez said that restoring sight in James’ left eye through a whole eye transplant was a moon shot from the get-go but that performing the surgery provided other benefits, as well. “Even if the eyelids were closed, it would give a better aesthetic than eye sockets that don’t have anything in it,” Rodriguez said.
Aaron James with his daughter Allie before the operation.Courtesy James family
James, who has had many operations since the accident, including one to remove his damaged left eye because of pain, said the face and whole eye transplant has been “life-changing” for him. “I can go out and I’m really not stared at anymore. I just look like a normal person walking down the street,” he said. Before the face and eye transplant, James could not taste because of the loss of his nose. He also could not eat solid food. “I just had a little hole in my mouth. My wife had to cook soups and puree them in a blender, and I had to drink them through a straw. That’s the only thing I could eat,” James said. James said he’s extremely grateful to the donor and the donor’s family. “Somebody had to pass away to make this happen, and the donor and the donor’s family, I can’t imagine having to make a decision like they had to do, and it’s something I think about every day,” James said. “I really want them to know that I’m grateful and I thank them every single day.” Rodriguez will continue to monitor signs of vitality in James’ eye in the coming years. “You can give a person a little bit of hope and push science forward,” Rodriguez said. “It may open up a new chapter they may not have thought was possible.”