PDA

View Full Version : Electric Shock Drowning - 42 fatalities


Philscbx
07-25-2012, 09:11 PM
A good friend in Texas who races boats mailed a note about this yesterday -
I was up all night reading everything I could fine and gathered most of the critical links I could fine
to share with you all so no one ever has to deal with this.

From now on - I wouldn't go near a craft using shore power without checking for voltage leaking while plugged to shore power.

The simple main tool for checking - HIOKI 3280-20
http://www.marinaguard.net/images/259_leak6as.jpg

The current can be so small - yet paralyze anyone in the water within range of the source.
2 VOLTS PER FOOT is considered lethal.
Less than 100 Milliamps - is dangerous - when 1000 Milliamps barely fires up a lightbulb.

NEVER Dive in after anyone who looks unconscious - The source is more than likely nearby - CUT the power source to that craft immediately.

NEVER hook up two crafts with extension cord coming from an onboard generator with unapproved devices.

PAY ATTENTION - to dead fish - birds near a craft - more than likely were electrocuted.

POWER LIFTS - by 120v - DIY Guys - Be Darn Careful to the MAX how it was done.

EXample -
2 dogs jump in from the owners boat -
Wife notices distress - jumps in - Husband jumps in to save Wife - They both died.
Caused by faulty light switch on craft nearby.

Years ago - a friend wanted me to install a power source on aluminum dock & lift so he could keep his pontoon batteries charged.

I refused - Instead - I used 10g underground cable with connections near the craft to connect jumpers with Anderson Quick connects to the batteries.
The other end 150 feet on shore is connected to the 12v source from Battery Charger on Ground fault circuit.
This is so much easier to monitor batteries from shore - than walking out to the craft -
tripping on extension cords at night - falling in with hot AC following you in.

Have a Safe Summer..


Hot Docks, Hot Boats and Electric Shock Drowning

THIS video link was reposted/fixed, but is unlisted - http://www.youtube.com/watch?v=O7-s_mdEPb0

http://www.youtube.com/user/ABYCAnnapolis/feed
*
http://www.marinaguard.net/page3.html

An undetected AC ground fault which produces a water path current in salt water may not create enough current density to affect a swimmer, even with a defective bonding conductor (ground).

Because of the much higher resistance of fresh water, however, the swimmer becomes the fault path conductor when the boat or dock ground is missing.

A voltage rise will occur on the underwater gear of the affected boat and cause a paralyzing low level current to flow in the swimmer.

Harbor Marine has cataloged over 115 "electric shock incidents" in marinas which have resulted in 42 fatalities (list available).

*
http://www.abycinc.org/
*

(Electric Shock Drowning Incidents – Marinas)
http://www.mikeholt.com/newsletters....ay&letterID=36
*

Google Search - Electrical Shock Drowning
http://www.google.com/search?client=...UTF-8&oe=UTF-8
*

SkiDog
07-25-2012, 09:47 PM
Thats all GREAT information that people really never think about.

scott023
07-26-2012, 09:59 AM
Some great info. Thanks for compiling it.

CruisinGA
07-26-2012, 11:22 AM
This makes me a little concerned...

We have an aluminum floating dock, with 120v power for lift, lights etc.

If you are sitting on the dock, with your feets in the water, and you touch something aluminum on the dock, you get a little buzz. Feels sorta like a 9v batt does on your tongue if you can remember being young enough to do that.

FrankSchwab
07-26-2012, 02:56 PM
Umm, get an electrician out there post-haste?

JohnE
07-26-2012, 06:21 PM
As an electricain I've read tons of stories on this topic. Mostly on the Mike Holt site. Search that if you want more reading. But marinas scare the hell out of me. I see enough shoddy work on land by electricians, nevermind work on piers by non professional installers.

Philscbx
07-27-2012, 12:22 AM
This makes me a little concerned...
with your feet in the water,
you get a little buzz. Feels sorta like a 9v batt does on your tongueI know, I felt this as well as a kid when my hand was in the water, and I wasn't sure what to think, but I suspect it was the dock light, and never dove in.

Philscbx
07-27-2012, 12:40 AM
http://www.youtube.com/watch?v=O7-s_mdEPb0
For some reason-this video link is unlisted I just discovered-hopefully it will work here.

4Cs
05-03-2016, 06:49 PM
There was a recent fatality on our lake a few weeks ago (see http://whnt.com/2016/04/18/taking-action-preventing-electric-shock-drowning/) due to Electric Shock Drowning (ESD). This story has me worried about it happening at or near my dock. I feel good about the wiring on my dock after doing quite a bit of research and having it examined. However, I am not so certain about the neighboring docks. Plus, they may all be good now, but how can one be certain about tomorrow (after corrosion, storms, other damage, etc.)?

To that end, does anyone have experience with this device? https://shockalarm.com/

Are there any other alarm alarm devices out there?

jsx30
05-03-2016, 11:59 PM
This was a tragedy. There is a Facebook page for smith lake that has some good info. I will post a link to the group. There are a few posts in the group about it. Apparently, Cullman electric and maybe Alabama power will install a voltage isolator that's supposed to keep a shock from occurring. We had our dock on smith wired this year by an experienced electrician. We have breakers at the walkway and gfci circuits. Even with this, we still turn off power to the dock when the kids are swimming. We also make them wear life jackets anytime the are near the water. We are in a slough but the water is about 60 ft deep at the end of my dock. It would not be hard to get lost down there...

https://m.facebook.com/groups/233998079977189?ref=bookmarks

jafo9
05-04-2016, 09:53 AM
I came across this a few days ago. Not sure about the price as its not listed on their website.

http://www.docklifeguard.org/index.html

The kids that died earlier this year on smith lake certainly hit close to home. We usually require life jackets for all swimmers, but as the kids get older, its hard to always enforce that rule.

Does anyone know if the force of the electricity diminishes as you get farther away from the dock? I've been wondering about the scenario where you see a drowning victim from being shocked. If you jump in, you get shocked too. Could you jump in with a vest and push them away from the dock to get to lower levels of electricity where your muscles aren't paralyzed?

Bubbacuse77
05-04-2016, 10:09 AM
For those of you that own these set ups an easy safe change is to insure the dock is grounded well and then have GFI breakers installed on all circuits feeding the dock power. I say GFI breakers vs outlets because if you end up with a ground leak prior to the GFI plug you will still have issues.

ahhudgins
05-04-2016, 11:21 AM
For those of you that own these set ups an easy safe change is to insure the dock is grounded well and then have GFI breakers installed on all circuits feeding the dock power. I say GFI breakers vs outlets because if you end up with a ground leak prior to the GFI plug you will still have issues.

^^^THIS IS THE ISSUE.

The water is at ground potential. If anyone feels a tingle while their feet are in the water while sitting on an aluminum dock, there is a voltage potential present on the DOCK. This is caused by 2 things: (1)Voltage being transferred to the metal in the dock by means of a number of ways. (2) Metal dock not be secured to a PROPER earth ground.

I deal with this crap every day at work. Our electricians wire plugs incorrectly and sometimes don't even run ground wires. :mad:

4Cs
05-04-2016, 11:30 AM
From what I've read about this topic, the current diminishes the further you are away from the dock. As such, it is a good idea to inform your family that if they sense a tingling sensation while in the water then they need to swim away from the dock, not towards it. Enforcing life jackets is the way to go as well. I think shutting off the power to the dock is also a good precaution.

I've read that outside of 100 yards from a dock, it is safe. That made me worry about the neighboring docks. I'm on a cove with a slough immediately to my right, so no worries from that direction. I feel good about my immediate neighbor's dock on my left (he's a retired builder and maintains his dock well), but the dock next to his is a real gem...extension cord power, artificial turf on the swim deck, and I'd be very shocked if it had GFI. It is within 100 yards, barely, so maybe I don't need to care. Nonetheless, I'll have to wander over to inspect the next time I'm at the lake.

ahhudgins
05-04-2016, 11:37 AM
This is my neighbor's (across the cove, thank God) DIY wiring. Boat lifts, lights, extra well pump for watering the lawn, and a nice little water pump for the metal slide.

4Cs
05-04-2016, 11:41 AM
Yikes!!! Thanks for the post...makes me feel better about my neighbor's dock two doors down.

scott023
05-04-2016, 11:46 AM
This is my neighbor's (across the cove, thank God) DIY wiring. Boat lifts, lights, extra well pump for watering the lawn, and a nice little water pump for the metal slide.

Yeah, that looks legit. :rolleyes:

snork
05-04-2016, 12:25 PM
This is my neighbor's (across the cove, thank God) DIY wiring. Boat lifts, lights, extra well pump for watering the lawn, and a nice little water pump for the metal slide.


***Fail***

jsx30
05-04-2016, 12:28 PM
From what I've read about this topic, the current diminishes the further you are away from the dock. As such, it is a good idea to inform your family that if they sense a tingling sensation while in the water then they need to swim away from the dock, not towards it. Enforcing life jackets is the way to go as well. I think shutting off the power to the dock is also a good precaution.

I've read that outside of 100 yards from a dock, it is safe. That made me worry about the neighboring docks. I'm on a cove with a slough immediately to my right, so no worries from that direction. I feel good about my immediate neighbor's dock on my left (he's a retired builder and maintains his dock well), but the dock next to his is a real gem...extension cord power, artificial turf on the swim deck, and I'd be very shocked if it had GFI. It is within 100 yards, barely, so maybe I don't need to care. Nonetheless, I'll have to wander over to inspect the next time I'm at the lake.

I'm worried about one of my neighbor's dock. I look at it and wonder how it keeps floating. I think part of the problem at smith is that 99% of the docks float. I was there last weekend and watched 2-3 ft white caps rolling over may dock along with 50 mph wind gusts from a storm rolling through. I'm back in a slough, it was probably worse out on the big water. Those docks get battered out there. I'm not surprised a wire gets frayed every once in a while.

TLR67
05-04-2016, 01:05 PM
Another great reason I love a trailer.....LOL.

hondaprlud
05-04-2016, 02:13 PM
This is my neighbor's (across the cove, thank God) DIY wiring. Boat lifts, lights, extra well pump for watering the lawn, and a nice little water pump for the metal slide.

geez dude, between work and home...:D:D:D

Lars
05-04-2016, 02:22 PM
I see these articles that get forwarded around now and then. I've got an aluminum roll in dock and a sub panel on shore with double pole 20A gfci breaker that feeds a split neutral outlet at the end of the dock. One outlet powers the lift, the other outlet powers a weed blower (two large loads, hence the split neutral) all inside liquid tight conduit with no junctions between the box and the outlet. With a proper GFCI breaker, I don't see how these situations could ever happen. Am I missing something?

ahhudgins
05-04-2016, 04:38 PM
geez dude, between work and home...:D:D:D

I'm off duty when I'm at the lake. :D

Bubbacuse77
05-04-2016, 09:54 PM
I see these articles that get forwarded around now and then. I've got an aluminum roll in dock and a sub panel on shore with double pole 20A gfci breaker that feeds a split neutral outlet at the end of the dock. One outlet powers the lift, the other outlet powers a weed blower (two large loads, hence the split neutral) all inside liquid tight conduit with no junctions between the box and the outlet. With a proper GFCI breaker, I don't see how these situations could ever happen. Am I missing something?

Your right a good GFI breaker should detect any lost voltage to ground and trip, unfortunately code never use to require GFI breakers and only outlets. So any short prior to the GFI plug is an issue. Then there are idiots that think they can DIY things without doing it per code and there is no protection at all.

CruisinGA
05-04-2016, 10:46 PM
Your right a good GFI breaker should detect any lost voltage to ground and trip, unfortunately code never use to require GFI breakers and only outlets. So any short prior to the GFI plug is an issue. Then there are idiots that think they can DIY things without doing it per code and there is no protection at all.

its easy enough to power the entire dock through a GFI outlet, which is how ours is wired

73blue
05-05-2016, 07:45 AM
From what I've read about this topic, the current diminishes the further you are away from the dock. As such, it is a good idea to inform your family that if they sense a tingling sensation while in the water then they need to swim away from the dock, not towards it. Enforcing life jackets is the way to go as well. I think shutting off the power to the dock is also a good precaution.

I've read that outside of 100 yards from a dock, it is safe. That made me worry about the neighboring docks. I'm on a cove with a slough immediately to my right, so no worries from that direction. I feel good about my immediate neighbor's dock on my left (he's a retired builder and maintains his dock well), but the dock next to his is a real gem...extension cord power, artificial turf on the swim deck, and I'd be very shocked if it had GFI. It is within 100 yards, barely, so maybe I don't need to care. Nonetheless, I'll have to wander over to inspect the next time I'm at the lake.

100 yards is a pretty arbitrary number. Generally, an electrical current is seeking the easiest or shortest path to the source (or ground). If the dock is properly grounded, in the event of a short or a fault in the neutral, then the grounded dock will carry the current back to ground. If the current hits water, it will spread out (because water is a poor conductor) until it hits a grounded conductor or ground itself. So, again generally speaking, the "danger zone" around an ungrounded dock is roughly equal to the depth of the water. If the water is 10 feet deep, then the danger is pretty much contained to a 10 foot radius around the source of the current, because at that point, the current has found its way back to ground.

Residential docks, even though some may look pretty ghetto-rigged, are fairly easy to protect. GFCI outlets and breakers are inexpensive unless you are running 50 amps or more to the dock. Those, combined with proper grounding, will protect you from incident. Just remember to test your outlets and breakers regularly (monthly at a minimum), as they can go bad over time.

disclaimer: I'm not an electrician, so take this with a nice grade of slaw.

CheddarB
05-05-2016, 08:51 AM
This is my neighbor's (across the cove, thank God) DIY wiring. Boat lifts, lights, extra well pump for watering the lawn, and a nice little water pump for the metal slide.

OSHA is this ok?

JohnE
05-05-2016, 12:27 PM
Some of you may want to check out this site:

http://www.electricshockdrowning.org/

There is a link to a Mike Holt discussion. Mike is one of the foremost NEC code experts in the country. He is also a competitive barefooter.