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[Mike Sokol]

As far as I can tell the cause of death is yet to be determined.

It seems that majority of time from an ESD it's really a drowning due to loss of muscle control. Since there's a voltage gradient in the sater of perhaps 5 volts per foot, if you put your arms out to your side they become a 5 ft wavelength dipole antenna. So that's about 25 volts hand-to-hand. Since your body has around 1K ohm resistance hand-to-hand, that suggests perhaps 25 mA of current. The threshold for loss of muscle control is around 20 mA of current, so at that point all of your muscles are contracting, and your nervous system can't overcome the AC electrical signal. Since you can't move your arms, you just sink below the surface and drown. In most cases of ESD the swimmer never actually reaches the electrified conduit or boat hull. They're usually found maybe 10 to 20 feet from the source of the current.

[David Allred]

It seems that majority of time from an ESD it's really a drowning due to loss of muscle control. Since there's a voltage gradient in the sater of perhaps 5 volts per foot, if you put your arms out to your side they become a 5 ft wavelength dipole antenna. So that's about 25 volts hand-to-hand. Since your body has around 1K ohm resistance hand-to-hand, that suggests perhaps 25 mA of current. The threshold for loss of muscle control is around 20 mA of current, so at that point all of your muscles are contracting, and your nervous system can't overcome the AC electrical signal. Since you can't move your arms, you just sink below the surface and drown. In most cases of ESD the swimmer never actually reaches the electrified conduit or boat hull. They're usually found maybe 10 to 20 feet from the source of the current.

In these situations, does it force an exhale, an inhale, a forced breathe hold scenario, a freeze, or what?  Probably outside of you expertize, but perhaps ......

[Mike Sokol]

In these situations, does it force an exhale, an inhale, a forced breathe hold scenario, a freeze, or what?  Probably outside of you expertize, but perhaps ......

Not sure, but here's what I DO know. You'll notice that your hand can clamp down harder on an object then release it. That's because you have more muscles in your hand for grasping than release. Above 20 mA current and every muscle in your body tries to contract and there's a tug of war. That's because your nervous system can't order a muscle to release, only contract. And that's why you can't let go of a hot wire. Now, I'm not sure, but I think you have more muscles compressing your diaphragm. If that's the case, then you'll expel all the air in your lungs if you're being shocked in the water. But I'll ask the guy who's studied ESD a lot more than me.

[Mike Sokol]

Here's a good follow-up story to the recent ESD deaths:

http://www.wsoctv.com/news/local/electric-shock-drowning-causes-dangers-in-waters/539927751

The three major groups I'm writing about ESD and Electrocution issues are:  RV owners and campgrounds, Boating consumers and Marinas, and Pro-Sound events and musicians. Even though these don't seem to be related, all of them involve human beings around electricity, and many times water. For example, how many times have you worked on an outside stage right after a quick rain and you're standing in puddles of water while hooking up gear? 

[ProSoundWeb Community]