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meridian 07-27-2012 07:53 AM

Stray current dangers
 
This was posted on another site a few days ago and I don't believe I've seen it here before. It gave me the best explaination of stray current problems, how to check for and fix them, and the real dangers associated with them. It is over an hour but every minute is informative. I'll be checking my boat this weekend.

Hot Docks, Hot Boats and Electric Shock Drowning - YouTube

Rambler 07-27-2012 09:20 AM

I think we've had two or three kids up in Tennessee or north Georgia who were electrocuted while swimming in or around the docks at the marina. Sometimes it's the marina's fault, but most often it's the boat owners fault.

CPseudonym 07-27-2012 10:31 AM

Very informative. Thank you for sharing

rwidman 07-27-2012 11:31 AM

Quote:

Originally Posted by Rambler (Post 96127)
I think we've had two or three kids up in Tennessee or north Georgia who were electrocuted while swimming in or around the docks at the marina. Sometimes it's the marina's fault, but most often it's the boat owners fault.

It couldn't be the kid's fault? Or their parent's fault?

Swimming in a marina is pretty much like playing in the street. A pretty foolish thing to do.

Rambler 07-27-2012 12:53 PM

Quote:

Originally Posted by rwidman (Post 96161)
It couldn't be the kid's fault?

Only if they pulled the power cords into the water.

Here is one of the stories:
3 children electrocuted while swimming in lakes; 3 drown in river - U.S. News

And it seems the one was apparently the fault of faulty wiring at the marina. Hardly the kids fault.
Tennessee marina where electrocution occurred files corrective plan

But in general, lacking the shock hazzard, swimming at the marina is not the safest thing to be doing. Still, kids don't know that. Parents should. Boaters even more so.

Scary 07-27-2012 01:48 PM

Very Sobering, every boater should see this.
 
Thanks my marina is full of old boats and house boats. I going to do a little checking other boats around my boat to make sure it's safe to be in the water. last year I rewired a Albin trawler that had been wired to the shore power with reverse polarity. It stared out with a simple job of installing a few ground fault interrupter outlets and just grew and grew as one thing after another reared it's ugly head. What I didn't think about was how little amperage it takes to kill. This boat had it been in fresh water would have been deadly. My current dock neighbor built his own 50' house boat and had a house electrician wire it. I'm going to check him out. Our delta water isn't pristine but it's fresh. Kids swim around the docks all the time. In spite of written warnings so have I. I don't think I'll be doing that anymore.

rwidman 07-27-2012 02:04 PM

Quote:

Originally Posted by Rambler (Post 96182)
Only if they pulled the power cords into the water. .

An undamaged power cord pulled into the water while still attached to the boat is not a haazzard. It's insulated.

A power cord not plugged into the boat, but pulled into the water should not be a hazzard because anyone who can follow written instructions will have turned the breaker off at the pedestal before unplugging the cord from the boat. Failing that, dropping the energized cord into the water should trip the breaker on the pedestal.

The hazzard I see to swimming in a marina is the danger of being hit by a moving boat. Just like playing in the street except that boats don't have brakes.

skipperdude 07-27-2012 04:27 PM

Swimming in a marina is pretty much like playing in the street. A pretty foolish thing to do.[/QUOTE]


Pretty much say's it all.

SD

CPseudonym 07-27-2012 06:46 PM

Quote:

Originally Posted by rwidman (Post 96187)
The hazzard I see to swimming in a marina is the danger of being hit by a moving boat. Just like playing in the street except that boats don't have brakes.

Must be a regional thing. I understand SD up in Alaska but the Carolina/Gulf Coastal areas and inland waterways? I see it quite often in my sliver of America.

FWIW If swimming in the marina is like "playing in the street" you must have some awful busy marinas in your area. The larger ones perhaps? Many of ours are smaller, 50 slips or less and fairly quiet to boot.

People swimming off private docks at their house is extremely common too.

Rather than painting all swimmers as irresponsible idiots incapable of using common sense, would it be more prudent to know the danger may exist and inspect for problems before you accidentally fall off the dock and get electrocuted? It never was exactly at the top of my list of possible dangers from slipping and falling in the water before I watched this video.

Steve 07-27-2012 06:58 PM

In the video it mentioned testing for current using a voltmeter, I didn't catch just how that is done anybody have a source for detailed instructions and aditional items needed for the meter and cables. I understand there is a similar test method to check for galvanic corrosion any reccomendations there?
Thanks,
steve W

CPseudonym 07-27-2012 10:02 PM

Quote:

Originally Posted by Steve
In the video it mentioned testing for current using a voltmeter, I didn't catch just how that is done anybody have a source for detailed instructions and aditional items needed for the meter and cables. I understand there is a similar test method to check for galvanic corrosion any reccomendations there?
Thanks,
steve W

I'd have to watch it again when I get to my computer but believe he gave a couple of email addresses for contact and additional information.

psneeld 07-28-2012 06:15 AM

Quote:

Originally Posted by CPseudonym (Post 96228)
Must be a regional thing. I understand SD up in Alaska but the Carolina/Gulf Coastal areas and inland waterways? I see it quite often in my sliver of America.

FWIW If swimming in the marina is like "playing in the street" you must have some awful busy marinas in your area. The larger ones perhaps? Many of ours are smaller, 50 slips or less and fairly quiet to boot.

People swimming off private docks at their house is extremely common too.

Rather than painting all swimmers as irresponsible idiots incapable of using common sense, would it be more prudent to know the danger may exist and inspect for problems before you accidentally fall off the dock and get electrocuted? It never was exactly at the top of my list of possible dangers from slipping and falling in the water before I watched this video.

Here in Jersey they swim in all the lagoons too which are way busier than the local marinas...they also swim in and across the intracoastal waterway. Heck they even jump off the bridges into the channels.

I'm not saying any of it's smart recreation...but many people do it so others think it's acceptble.

Then you have the people who tube, ski, kneeboard the busy ntracoastal and even have people in tubes when the pull up to the very busy fuel docks.

Around here....it's vacation mentality..."I'm on vacation having fun...therefore everyone else has to give me room to be happy":D

jleonard 07-28-2012 08:17 PM

I am on the great loop in Canada and so many swim in marinas it's crazy. I caution about electrocution, I learned about this manyyears ago, but people just shrug their shoulders and really don't care about the potential danger.

psneeld 07-29-2012 05:57 AM

I wonder what professional divers (hull cleaning, zincs, etc) do before entering the water to check for electrocution? Many non-pros do the same thing all over, all the time.

It's not really swimming so I'm not sure it violates the "no swimming signs" that many marinas post.

At my marina the current is at least 10X the danger for swimmers than boats..unless you go in at slack curent.

Woodsong 07-31-2012 09:35 AM

I would LOVE to know how to check for voltage in the water- seems it would be a very practical thing to know how to safely and correctly do. It also amazes me how many times we see people swimming in marinas- besides all the cables running under water and support bars for our typical floating docks, there is always the electricity concern and how parents don't think of this before letting their kids swim is beyond me. If my kids want to swim at the dock we either go to the marina pool or kayak or dinghy out of the marina and jump in if we are not taking out the big boat!

psneeld 07-31-2012 10:26 AM

Quote:

Originally Posted by Woodsong (Post 96649)
I would LOVE to know how to check for voltage in the water- seems it would be a very practical thing to know how to safely and correctly do. It also amazes me how many times we see people swimming in marinas- besides all the cables running under water and support bars for our typical floating docks, there is always the electricity concern and how parents don't think of this before letting their kids swim is beyond me. If my kids want to swim at the dock we either go to the marina pool or kayak or dinghy out of the marina and jump in if we are not taking out the big boat!

I wonder if it's like getting hit by lightning...a one in a XXX chance.

When my marina got rewired a few years back...the electrician said to me "holy shi*, you could plug a toaster in my assistance vessel slip. I and several divers had been under the boat several times in the preceding few years with no sensation anything was wrong.

So I don't know... but I guess I'll ask the pro divers I know and do some research...if I or anyone finds the answer that IS PRACTICAL FOR MOST OF US...it probably would be greatly appreciated if it gets posted!:thumb:

rwidman 07-31-2012 11:00 AM

When I say that swimming in a marina is "stupid", I'm not talking about divers who clean boats in a slip and I'm not talking about people swiming around private docks, I'm talking about swimming back and forth across the fairway with boats coming and going. The risk is being hit by a moving boat or causing a boat operator to wreck while trying to avoid the swimmer.

I understand how a ten year old child might not be able to think this out, but his parents should be able to. So should older children.

We have this situation in my marina from time to time when dry stack boaters take a slip for the weekend. :banghead:

Woodsong 07-31-2012 11:45 AM

Quote:

Originally Posted by psneeld (Post 96656)
I wonder if it's like getting hit by lightning...a one in a XXX chance.

When my marina got rewired a few years back...the electrician said to me "holy shi*, you could plug a toaster in my assistance vessel slip. I and several divers had been under the boat several times in the preceding few years with no sensation anything was wrong.

So I don't know... but I guess I'll ask the pro divers I know and do some research...if I or anyone finds the answer that IS PRACTICAL FOR MOST OF US...it probably would be greatly appreciated if it gets posted!:thumb:

From everything I have ever read the risk of shock is much greater in freshwater environments than salt water. I see divers hop in at the docks up here on the river all the time without testing anything first and I always think- dang- I hope all the electrical is ok!

psneeld 07-31-2012 12:46 PM

Quote:

Originally Posted by rwidman (Post 96660)
When I say that swimming in a marina is "stupid", I'm not talking about divers who clean boats in a slip and I'm not talking about people swiming around private docks, I'm talking about swimming back and forth across the fairway with boats coming and going. The risk is being hit by a moving boat or causing a boat operator to wreck while trying to avoid the swimmer.

I understand how a ten year old child might not be able to think this out, but his parents should be able to. So should older children.

We have this situation in my marina from time to time when dry stack boaters take a slip for the weekend. :banghead:

Ok..whatever..it's done all around the globe...stupid or not...better be carefull of people in the water....:rolleyes:

fstbttms 08-01-2012 01:43 AM

Quote:

Originally Posted by psneeld (Post 96346)
I wonder what professional divers (hull cleaning, zincs, etc) do before entering the water to check for electrocution?

A prudent hull cleaner will unplug the boat he is working on from the shorepower, however, many (probably most) do not and never suffer any problems.

That being said, almost all electric shock drownings occur in freshwater. It is almost unheard of in saltwater. To say that swimming in a (saltwater) marina is foolish or even particularly dangerous is simply ignorant. For example, in the 18 years that I have been cleaning boat bottoms here in the Bay Area, well over 1,000,000 in-water service events have taken place, virtually of them in marinas, without a single electric shock drowning occurring.


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