ProSoundWeb Community

Please login or register.

Login with username, password and session length
Advanced search  

Pages: [1] 2  All   Go Down

Author Topic: Swimming Pool Electrocution  (Read 8921 times)

Mike Sokol

  • Moderator
  • Hero Member
  • *****
  • Offline Offline
  • Posts: 3361
  • Lead instructor for the No~Shock~Zone
    • No~Shock~Zone Electrical Safety
Swimming Pool Electrocution
« on: March 31, 2016, 03:58:34 PM »

Anther forum member brought this to my attention (Thanks, Tim), and it's a very sad story about a SF business executive being electrocuted in his swimming pool while trying to save his children from shock-drowning. http://www.sfgate.com/bayarea/article/Silicon-Valley-exec-dies-trying-to-save-daughter-7216737.php

Since we're now entering pool season, and many of us may be doing sound gigs around swimming pools and open water, you need to extra vigilant about proper equipment grounding.

I've contacted the reporter who wrote this story to get more intel, but it's been suggested that a wiring problem with the pool lights electrified the water.  I've been trying to get some traction with OSHA to offer CPR and Electrical Awareness Training to pro-sound crews, so if any of you are certified CPR instructors or EMT's, please contact me directly to discuss.

Jonathan Johnson

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 3209
  • Southwest Washington (state, not DC)
Re: Swimming Pool Electrocution
« Reply #1 on: March 31, 2016, 05:49:21 PM »

Seems to me having an EPO (Emergency Power Off) switch for swimming pool electrics (lights, pumps, and heaters) would be a good idea. In addition to electric shock, I've heard of people being trapped against pump intakes. (The lights and heaters, at least, should be GFI protected anyway.)

Of course, that assumes that people will have the presence of mind to shut off the power in an emergency situation. Perhaps the EPO circuit could be linked to emergency equipment stowage: if someone grabs a life ring, for example, all power is cut off (and an alarm is sounded). In facilities equipped with monitored alarms, EPO could alert emergency responders automatically.

The thing is, most people who might respond to a swimmer in distress won't know whether electricity is involved or not. In an emergency, you can't presume to know the cause before intervening, so signage and training should be to shut off power in ANY swimmer-in-distress emergency.

I know this is out of the realm of "audio", but I figured I might as well share the thought. It's certainly not a well-developed idea, there are many things to consider. Maybe someone reading this will be able to protect other people using these ideas as a basis.

Well, bringing this back to "audio", baptismal pools with electrics should also have an EPO. In addition to an EPO switch near the pool, put one in the control booth -- and train people to recognize a person in distress. That may not be the Spirit moving them...
Logged
Stop confusing the issue with facts and logic!

John Roberts {JR}

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 17176
  • Hickory, Mississippi, USA
    • Resotune
Re: Swimming Pool Electrocution
« Reply #2 on: March 31, 2016, 05:53:44 PM »

Maybe teach the pool puppy (the automatic cleaner every pool uses) to bark if it senses any voltage gradient.

Seems this should all be preventable.

JR
Logged
Cancel the "cancel culture". Do not participate in mob hatred.

Corey Scogin

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1266
  • Birmingham, AL, US
Re: Swimming Pool Electrocution
« Reply #3 on: March 31, 2016, 06:03:10 PM »

I'd be interested in the specifics.
How was current flowing in such a way to electrocute a swimmer?
Was the person in contact with an electrified piece of metal? Or a grounded one?
Is the resistance of pool water higher than the resistance of a human body such that merely being in the water may cause current to flow through a person?
Do any of these questions even matter because there are too many variables to consider, they'll differ in every situation, and the entire system should be GFCI protected?
Logged

Mike Sokol

  • Moderator
  • Hero Member
  • *****
  • Offline Offline
  • Posts: 3361
  • Lead instructor for the No~Shock~Zone
    • No~Shock~Zone Electrical Safety
Re: Swimming Pool Electrocution
« Reply #4 on: March 31, 2016, 06:08:01 PM »

Of course, that assumes that people will have the presence of mind to shut off the power in an emergency situation.

I'll do more digging, but my point of posting this thread is to make all of you aware of the extra dangers of electric shock around water. Typically a swimmer begins to lose control of their muscles the closer they get to the source of the leakage current. And when you can't move your muscles, you just slip below the surface and drown. It's really important to turn off the source of the current BEFORE getting in the water to help someone in distress. And, of course, hindsight is 20-20 and I'm sure that most times nobody is aware there's a shock that's causing the swimmers to be in distress. So education is the key to saving lives. That and a big cutoff switch with a GFCI are probably the best ways to save lives.

Mike Sokol

  • Moderator
  • Hero Member
  • *****
  • Offline Offline
  • Posts: 3361
  • Lead instructor for the No~Shock~Zone
    • No~Shock~Zone Electrical Safety
Re: Swimming Pool Electrocution
« Reply #5 on: March 31, 2016, 06:11:07 PM »

I'd be interested in the specifics.
How was current flowing in such a way to electrocute a swimmer?
Was the person in contact with an electrified piece of metal? Or a grounded one?
Is the resistance of pool water higher than the resistance of a human body such that merely being in the water may cause current to flow through a person?
Do any of these questions even matter because there are too many variables to consider, they'll differ in every situation, and the entire system should be GFCI protected?

It's called ESD for Electric Shock Drowning, and the freshwater boating industry has been working on this for a few years. In fact, I've consulted with some of their presenters about how it works. See here for specifics, and I can answer questions on it as well. http://www.boatus.com/seaworthy/ESD.asp

And here's a really good basic description from my buddy Dave Rifkin: http://www.qualitymarineservices.net/
« Last Edit: March 31, 2016, 06:13:18 PM by Mike Sokol »
Logged

Jonathan Johnson

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 3209
  • Southwest Washington (state, not DC)
Re: Swimming Pool Electrocution
« Reply #6 on: March 31, 2016, 06:13:12 PM »

That and a big cutoff switch with a GFCI are probably the best ways to save lives.

A GFCI is a must... but I wouldn't trust it to be the sole means for interrupting voltage. A Big Red Button would be a worthwhile addition.

Do commercially-produced audio distros provide for an EPO circuit? I know that some UPSs do.
Logged
Stop confusing the issue with facts and logic!

Tim McCulloch

  • SR Forums
  • Hero Member
  • *
  • Offline Offline
  • Posts: 23741
  • Wichita, Kansas USA
Re: Swimming Pool Electrocution
« Reply #7 on: March 31, 2016, 06:58:35 PM »

A GFCI is a must... but I wouldn't trust it to be the sole means for interrupting voltage. A Big Red Button would be a worthwhile addition.

Do commercially-produced audio distros provide for an EPO circuit? I know that some UPSs do.

It's the big circuit breaker on the front.  They can be ordered with shunt trip terminals for remote kill.
« Last Edit: April 01, 2016, 12:20:03 AM by Tim McCulloch »
Logged
"If you're passing on your way, from Palm Springs to L.A., Give a wave to good ol' Dave, Say hello to progress and goodbye to the Moonlight Motor Inn." - Steve Spurgin, Moonlight Motor Inn

Stephen Swaffer

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 2672
Re: Swimming Pool Electrocution
« Reply #8 on: March 31, 2016, 10:29:53 PM »

One of the changes to the NEC in 2014 was a requirement to bond the pool water.  No doubt to make sure there is a good path to trip GFCIs.  It appears to me that nearly everything anywhere near a pool must be GFCI protected or low voltage.

The problem is, virtually no one requires older installs to be brought up to date-so pool that is even 5 or 6 years old could have issues addressed by 2 cycles of code updates.

Maintenance is another issue-how many of the GFCI's are tested every 30 days as required?  At a bare minimum-make sure yours get tested before the season starts!
Logged
Steve Swaffer

Frank Koenig

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1318
  • Palo Alto, CA USA
Re: Swimming Pool Electrocution
« Reply #9 on: March 31, 2016, 11:21:28 PM »

This one hit pretty close to home. I didn't know the victim personally but he and his family are good friends of a close friend of mine. His kids and my friend's grand kids hung out together a lot and, needless to say, the grand kids, while not present at the event, are devastated. To be clear, this occurred in the city of Palm Springs, California, not at the victim's residence in Burlingame. I think it was at an Air B&B or the like.

I am very interested in learning the results of any investigation both for my own edification and, as I'm considered the "electrical guy" in my group, to answer others' questions.  So, Mike, I really appreciate anything you can dig up through your channels. I'm not holding my breath for the media. And no, I'm not getting involved the the inevitable lawsuits.

As to the bonding of pools, it is interesting that "bonding the water" is a recent addition to the code. When my folks had a pool built back in 1968, I clearly recall that there were ground clamps on the rebar cage of the pool with  copper wires running to clamps on all the copper pipes, as they used at that time. The whole shebang got embedded in the gunite. I guess now with PVC pipe being the norm it take a bit more explicit wiring to achieve a good bond.

I've seen E-stop mushroom switches on some public pools. I don't know if and where they are required, but they sound like a really good idea.

--Frank

 
Logged
"Nature abhors a vacuum tube." -- John Pierce, Bell Labs

ProSoundWeb Community

Re: Swimming Pool Electrocution
« Reply #9 on: March 31, 2016, 11:21:28 PM »


Pages: [1] 2  All   Go Up
 



Site Hosted By Ashdown Technologies, Inc.

Page created in 0.038 seconds with 24 queries.