ASK THE EXPERT by Elizabeth Altick
Silent Danger North Shore Safety’s Steve Kensinger warns of the risk of Electric Shock Drowning in freshwater. LB: What causes Electric Shock Drowning (ESD)?
LB: What can marinas do to eliminate stray current?
Kensinger: ESD is caused when alternating current (AC) flows through freshwater and encounters a human body. The current tries to pass through the body and causes muscular paralysis, which ultimately results in drowning.
Kensinger: Marina owners should install GFCIs on all shorepower pedestals and wiring circuits. Qualified electricians should regularly inspect marinas. In some cases, a strict no-swimming policy is appropriate. We are currently working with several freshwater marinas throughout the country to mitigate the high levels of electric current in their water.
LB: How common is ESD?
Kensinger: ESD is a relatively new problem because 20 years ago fewer docks were powered. Given the prevalence of electric boat lifts, lights and shore-power connections, the risk of ESD is real today. In the 1980s, it was considered safe to dive off a dock without a thought of ESD. Today, swimming off a dock or diving under a boat can result in tragedy.
LB: How can a swimmer be safe from ESD?
Kensinger: Avoid swimming around boats, docks and marinas that use AC power. LB: How do you know if a person is drowning due to ESD?
Kensinger: An ESD victim is often confused, may be able to shout, and will feel numbness, tingling, pain and paralysis. ESD victims look distressed and may simply roll onto their backs (if wearing a life jacket) or roll face down into the water, totally unresponsive. ESD victims can be instantly paralyzed and may not move at all.
LB: What is the typical source of electrical current in the water?
Kensinger: Faulty wiring, improper grounding and faulty appliances on-board are contributing factors. Electricity enters the water from faulty wiring in a nearby dock or marina, or from a boat connected to a power supply. Often, the fault occurring from the boat only leaks current into the water when a switch is flipped. LB: How much electricity poses a danger?
PHOTOS COURTESY OF NORTH SHORE SAFETY
Kensinger: In freshwater, minimal amounts of alternating current can kill. Just 15 milliamps (mA) can cause paralysis, while 100 mA can cause death within a few seconds. (Source: Captain David Rifkin, USN retired). LB: What can boaters do to prevent ESD? How do your products help?
Kensinger: Boaters, dock owners and marinas can contact North Shore Safety to discuss which of our ground fault circuit interrupters (GFCIs) or equipment leakage circuit interrupters (ELCIs) would work. Our product senses leakage and kills power to the source, preventing electrical leakage into the water. Have your boat inspected by an electrician with current ABYC Electrical Certification or by an ABYC Certified Technician.
North Shore Safety’s GFCI and ELCI products.
CONTACT North Shore Safety, Ltd. 7335 Production Dr. Mentor, OH 44060 440-205-9188 SKENSINGER@NSSLTD.COM NSSLTD.COM
LB: What should a bystander do?
Kensinger: Call 911. Do not go into the water or touch the victim. Shut off the source of the electrical current. Try to reach them with a wooden oar or throw a flotation device. Once you have retrieved the person, start CPR if there is no pulse. Automated Electrical Defibrillators are also becoming more common — just make sure the victim’s chest is dry. LB: Is ESD an equal risk in fresh and salt water?
Kensinger: While ESD can occur in saltwater environments, the risk is much higher in freshwater because of differences in conductivity. Salt water naturally has a high conductivity and low resistance, so leaking current in water tends to go around a human body to stay in the low resistant salt water. In freshwater, which has low conductivity and high resistance, the electrical fault or current seeks a path of lower resistance to get back to its source — and a human body can serve as this low resistance path. Freshwater is nearly 70 times more resistant than salt water. ★
ELIZABETH ALTICK specializes in recreational marine, cultural and humaninterest subjects. She was formerly executive editor of a recreational boating magazine.
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