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It’s sweet summertime and time to take the boat out, go to the lake and enjoy the cool, clear water, but a hidden danger could be present in our recreational waters that not many of us know about. It’s called Electric Shock Drowning or ESD and it’s entirely preventable. ESD is the result of the passage of a typically low level AC current through the body with sufficient force to cause skeletal muscular paralysis. This renders the victim unable to help himself or herself while immersed in fresh water – essentially resulting in the drowning of the victim.

Although electric shock drowning can occur in any location where electricity is provided near water, the majority of ESD deaths occur in public and private marinas and docks. Unfortunately, the typical victim of electric shock drowning is a child swimming in or around a marina or dock where electricity is present. The electricity that enters the water and causes electric shock drowning originates from the wiring of the dock or marina, or from boats that are connected to the marina’s or dock’s power supply.

Lethal amounts of electricity are measured in milliamps, or thousandths of an amp. When flowing directly through the human body, these tiny amounts can interfere with nerves and muscles.

Why does this type of drowning usually occur in fresh water? Salt water is 50-1,000 times more conductive than fresh water. When the human body is wet, its conductivity lies between the two, but is much closer to saltwater than fresh. In saltwater, the body slows electricity down, so most of it will go around the swimmer on its way back to ground, unless the swimmer grabs something that’s electrified. But, in fresh water, the current gets “stuck” trying to return to its source and generates voltage gradients that will take a shortcut through the human body. 100037002

ESD is a silent killer because there is no visible warning or way to tell if the water surrounding a boat, marina or dock is energized. In most cases, victims do not immediately feel current when they swim in the water around a marina or dock, which gives the victims the false impression that it is “safe” to swim.
Electricity usually enters the water when an electrical fault occurs aboard a nearby boat. A fault may occur only when a light switch is turned on or other electrical device aboard the vessel cycles on. The water can appear and feel perfectly safe, but become energized with deadly electricity in a split second.

In most cases of ESD, the victim’s muscles become paralyzed by the electrical current, and he or she is unable to swim, resulting in drowning. Unless there is a witness nearby to experience and report the sensation of electric shock in the water, the victim’s death is typically labeled a common drowning.
According to the Electric Shock Drowning Prevention Association, since experts began tracking this silent killer, there have been over 60 incidents of ESD, several near misses and likely hundreds of deaths that have gone unreported. Until recently, there was very little public awareness about the danger of ESD and as a result, it continues to kill. 50916002

What can we do to prevent electric shock drowning?
• Never swim in or near marinas, docks or boat yards.
• Tell others about the dangers of ESD. Most people have never heard of it and are unaware of the danger.
• If you own a boat, have it inspected by an electrician with current American Boat and Yacht Council (ABYC) Electrical Certification or by an ABYC Certified Technician. Boats with alternating current (AC) systems should have isolation transformers or equipment leakage circuit interrupter (ELCI) protection, comply with ABYC standards & should be serviced by an ABYC Certified Technician.

This summer, enjoy your boat, the water and all the recreational opportunities Northwest Florida has to offer – just remain aware of the possible dangers to you and your loved ones that could be hidden just beneath the surface of that cold, clear water.