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Author Topic: Electric Shock Drowning  (Read 2461 times)

Mike Sokol

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Electric Shock Drowning
« on: June 02, 2016, 08:34:24 am »

It's that time of year again when everyone jumps in the pool or the boat dock. There's already been 3 new deaths attributed to ESD (Electric Shock Drowning) cause by voltage gradients in the water. Here's a brief report from Mike Holt's excellent website.

Mike Sokol

Here's a link to the newsletter: http://www.mikeholt.com/newsletters.php?action=display&letterID=1665

In last week's newsletter we told of the tragic death of a teenage girl in Alabama that is being attributed to electric shock drowning; we included a link to the website of David Rifkin and Kevin Ritz, The Electric Shock Drowning Prevention Association. David Rifkin has provided us with the updated report of Electric Shock Drowning Incidents.

This year’s update includes 3 new deaths. We like to send this update at this time each year when swimming weather is upon us. The information and list is maintained and provided by Quality Marine Services, LLC in Jacksonville, FL. If you have any questions or for more information please contact: David Rifkin 904-382-7868 qualitymarinesvcs@comcast.net. Jim Shafer, the originator of this list is currently unable to participate in this area.

 Electric Shock Drowning Incidents - Marinas©

(In-Water electrocution fatalities included - Revised 5/9/2016)

Low level ground fault leakage in the marina AC shore power system can cause lethal potentials to appear on any underwater metal surface – either on a boat or on the dock. In fresh water the electric field surrounding this surface can paralyze a swimmer. There is no warning that this condition exists, and it has resulted in a number of drownings. Further, there is no post-mortem evidence that electric shock was the cause. Therefore, many of the fatalities listed below are only the known electric shock caused drownings, which were investigated because of circumstantial evidence, i.e., multiple deaths, eye witnesses, considerable distress, cries for help, shock sensation reported by rescuers, etc.

Our studies have shown that, in salt water, the high voltage gradients required for electric shock drowning could not be established with the available fault current levels. In no cases can we attribute cause of death to electric shock drowning in salt water.

We do not know the exact wiring errors or ground faults that created some of the incidents listed below, but it can be assumed that an energized AC conductor (L1 or L2) came in contact with a bonded (grounded) metal object, and coincidently, this object was not connected to the shore bonding (grounding) system. This caused a voltage to appear on these under-water metal objects (both on boats and docks). This created a lethal electric field around the object (a person in this electric field can be paralyzed leading to drowning, or direct electrocution). This was true in every case that was investigated.

No database has been found that catalogs “Electric Shock Drowning” – our term for this phenomenon. The incidents listed below came from various sources, i.e., investigation, press, third party, and eye witness reports. Dates and details are missing for some. There is no way to know what fraction of the total fatalities this listing represents, but it may be reasonable to assume that it could be small. We have no reports of fatalities in salt water due to electric shock drowning.

Some of the fatalities listed here were actually caused by ventricular fibrillation (electrocution), because the victim’s head was reported not to have been submerged. They are technically not drownings but are listed here since the causes are similar to drowning by electric shock.

 

1. Apr 16, 2016

Smith Lake, Priceville, AL.  Two teenage girls entered the water from a private dock.  Both girls were getting shocked in the water.  One girl drowned, the other treated and released from hospital.  The victim’s father and his son jumped into the water to assist.  The father blacked out after both were feeling the shocks.  The power was turned off at the house, after which the father came to and survived along with son.  A missing ground and faulty lighting fixture are suspected to be the cause.

2. Mar 27, 2016

Palm Springs, CA, Indian Canyons neighborhood.  Six people were shocked in a private swimming pool, one of them a man who jumped in to rescue his daughter.  He was overcome by electric shock and pronounced dead at the hospital.  The 5 others were treated, and one young girl remained hospitalized in critical condition.  Faulty pool wiring is suspected as the cause.  Homes were built in 1963, but not sure of the age of the swimming pool.

3.  June 21, 2015

Lake of the Ozarks, Woods Hollow Cove, 22.2 mile marker, MO.  A 21 year old man and fellow swimmer felt electricity in the water near a dock.  The 21 year old grabbed a dock ladder to get out when he was electrocuted and fell back into the water.  Someone ran ashore and turned off the power likely saving the other man in the water.  A faulty junction box between dock and residence is suspected.  The occupants tried to reset the circuit breaker but it would trip after 10-15 seconds of being turned on.  The last attempt to turn the breaker on coincided with the 2 swimmers being near the dock as it got dark (breaker controlled dock lights).
« Last Edit: June 02, 2016, 08:36:31 am by Mike Sokol »
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Stephen Swaffer

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Re: Electric Shock Drowning
« Reply #1 on: June 02, 2016, 02:37:03 pm »

I find the use of "suspected" as the cause somewhat disconcerting. You can be sure I am going to make sure I have the problem resolved before letting anyone near the water after an incident like these!
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Frank Koenig

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Re: Electric Shock Drowning
« Reply #2 on: June 03, 2016, 12:21:41 pm »

This makes me wonder if it might be possible to develop a safe, simple-to-use probe that could be used to check out a body of water before jumping in. The two methods that immediately come to mind are a pair of electrodes that measure the field gradient, or a single electrode that's referenced to the shore grounding/bonding system. Or maybe such a thing already exists? Best, --Frank

OK, that should be "potential gradient" or "field".  Field gradient doesn't make sense  ???
« Last Edit: June 03, 2016, 12:28:57 pm by Frank Koenig »
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John Roberts {JR}

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Re: Electric Shock Drowning
« Reply #3 on: June 03, 2016, 02:08:12 pm »

Perhaps GFCI on the shore power... ? The indication there is a problem would be it shutting down.

JR
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Jonathan Johnson

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Re: Electric Shock Drowning
« Reply #4 on: June 03, 2016, 03:23:52 pm »

Perhaps GFCI on the shore power... ? The indication there is a problem would be it shutting down.

JR

As I understand it, most European countries require it. Here in America, many managers are too willing to put a monetary value on life and consider it a business decision. If the life is worth less than implementing the cost of safety equipment...... well, that just makes us look like some third world countries in terms of how we value human life.

Of course we can't banish stupidity. That would be impossible. But this problem can be clearly described and there is a proven protective solution (GFCI), and the cost is not unreasonable. It's a fairly simple retrofit; at most a few thousand dollars per marina. The problem is overcoming the "it will never happen here" mentality. We don't wear goggles because we expect to have an object impale our eye; we wear them because it might happen. Protective gear is used primarily to protect from the unexpected hazardous situation.

There will be some objection with regard to "nuisance" tripping. Some of that can be mitigated with staged protection: high-current (like 20 mA) on the feeders, stepping down to lower current GFCI (6 mA) on the branch circuits. Then one boat doesn't take out the entire marina.

For docks that just have lighting, make it 12V DC lighting with the power supply on the shore. If there's no need for AC power on the dock, don't put AC power on the dock.

There's no mystery here that requires a dozen years of studies to determine the cause and best solutions. All that's already known. Do the right thing and put in the protective gear.
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David Buckley

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Re: Electric Shock Drowning
« Reply #5 on: June 03, 2016, 03:47:55 pm »

These types of incidents are relatively rare in the civilised first world countries, the USA is an outlier in this respect.

There are a number of things done with electricity in the USA that makes this sort of thing more probable, and in some cases the issue is dissimilar ground potentials leading to potential gradients, and this cant be solved with a GFCI.
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Frank Koenig

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Re: Electric Shock Drowning
« Reply #6 on: June 03, 2016, 03:55:27 pm »

Perhaps GFCI on the shore power... ? The indication there is a problem would be it shutting down. JR

My thought was to have a self-contained probe is that provides an independent check for safety, much like an NCVT. If stages were always wired correctly and were always on GFCIs (with all that implies) we wouldn't need  meters, NCVTs, etc., either. --Frank
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Stephen Swaffer

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Re: Electric Shock Drowning
« Reply #7 on: June 03, 2016, 11:36:01 pm »

As I understand it, most European countries require it. Here in America, many managers are too willing to put a monetary value on life and consider it a business decision. If the life is worth less than implementing the cost of safety equipment...... well, that just makes us look like some third world countries in terms of how we value human life.

Of course we can't banish stupidity. That would be impossible. But this problem can be clearly described and there is a proven protective solution (GFCI), and the cost is not unreasonable. It's a fairly simple retrofit; at most a few thousand dollars per marina. The problem is overcoming the "it will never happen here" mentality. We don't wear goggles because we expect to have an object impale our eye; we wear them because it might happen. Protective gear is used primarily to protect from the unexpected hazardous situation.

There will be some objection with regard to "nuisance" tripping. Some of that can be mitigated with staged protection: high-current (like 20 mA) on the feeders, stepping down to lower current GFCI (6 mA) on the branch circuits. Then one boat doesn't take out the entire marina.

For docks that just have lighting, make it 12V DC lighting with the power supply on the shore. If there's no need for AC power on the dock, don't put AC power on the dock.

There's no mystery here that requires a dozen years of studies to determine the cause and best solutions. All that's already known. Do the right thing and put in the protective gear.

There is a general resistance to being told what to do-it ventures into politics in that those in the US usually prefer less regulation.  We have a tendency to think that "they" should be made to be safe-but what we are doing is safe-even if the inspector says it isn't.

Unfortunately, it is rarely the person who chooses not to invest in the available safety technology that is affected by its lack of use.
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Steve Swaffer

John Roberts {JR}

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Re: Electric Shock Drowning
« Reply #8 on: June 04, 2016, 12:10:24 am »

I am not a fan of lawsuits but it seems liability should motivate people to be more careful about exposing innocents to hazards.

When the guitar player got killed by a RPBG outlet they sued Peavey who made the guitar amps he had plugged into the rouge outlet, no doubt because Peavey had deep pockets that ambulance-chaser lawyers like to pursue.

I doubt the person actually responsible for the miswired outlet was ever held culpable.

JR
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Re: Electric Shock Drowning
« Reply #8 on: June 04, 2016, 12:10:24 am »


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