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Posted By: Trumpy Electrocution Question - 06/21/03 06:08 AM
Hi there Guys,
I had this really strange email just this last week, from a lady that I had never even heard of, she had this question for me:
If you are in a bath, and you have a heater or other appliance and it falls into the bath while you are in it, will you get Electrocuted?.(disregard GFCI/RCD protection).
Having never tried this out for myself, I would not encourage anyone else to have a go at it, either!!, I was just wondering how a shock would occur?.
Could you people please help me with this one, as it is really killing me thinking about it.

[This message has been edited by Trumpy (edited 06-21-2003).]
Posted By: Zapped Re: Electrocution Question - 06/21/03 04:08 PM
Yes, I would imagine so.

Current will flow throught the water, and you, on it's way to completing the circuit (hot to neutral).

This experiment has been done by unwitting test subjects over the years, both accidental and not so accidental.

Don't try this at home!
Posted By: sparky Re: Electrocution Question - 06/21/03 04:49 PM
Is how the human body would conduct current immersed the Q?? Does the mineral content of the water matter?
Posted By: Thom Re: Electrocution Question - 06/21/03 05:38 PM
I would think you would be OK unless you came in direct contact with the unit. You might get a tingle. Wouldn't the circuit still be complete in the case of a heater?
Posted By: wa2ise Re: Electrocution Question - 06/22/03 12:12 AM
One's body, which for this is equivalent to a sack of dirty water with lots of salt and such in it, would probably pass most of the leakage current from the heater. Current would flow from the heater thru many paths in the water (which is likely to be somewhat dirty) to your body, and then thru your body to other areas of the body and exit thru more multiple paths in the water to a grounded faucet and drain hardware. And the porcelin coating on a metal tub is likely to have many small cracks, creating more current paths....
Posted By: sparky Re: Electrocution Question - 06/22/03 12:38 AM
my first reaction to the Q would be how many variables exist, proper grounding of the heater, non-FPE breakers, number of conductable paths, as well as conductables.

would it be riske' to assume that normally there would be a spike of power, until an OCPD reacts, that would include more umph* within the unit, and decreasing umph as the distance from it increases?


*technically speaking.....
Posted By: Trumpy Re: Electrocution Question - 06/22/03 05:48 AM
Guys,
Sorry about the rather vague question.
But assuming that the heater is a Class II
appliance (Having Double Insulation, as the majority of Domestic Heaters these days, have an outer shell of plastic).
Also assuming that a person was lying in the bath and not touching the plug-hole or the taps(faucets).
How would(or could) a shock occur, is it merely by the current flow through the water?.
Remember that the current has to flow through the heart, to cause fibrillation, before a true shock would occur.
Thanks for your input fella's.
I'm still trying to work out how this lady got my e-mail address, let alone work out the actual problem! [Linked Image]
Posted By: pauluk Re: Electrocution Question - 06/22/03 10:23 AM
Possibly from your ECN member profile?

There are bound to be currents of some magnitude flowing through parts of the water, but the actual paths and levels are going to be very dependent upon the salt/mineral content of that water, how far away the person is from the energized heater, and so on.

It's not something I'd want to put the test in a practical experiment.... [Linked Image]
Posted By: Thom Re: Electrocution Question - 06/22/03 10:56 AM
Why don't I get shocked when I turn on the hot water from the hot water tank? We have 240v directly in contact with the water.
Posted By: zapped208 Re: Electrocution Question - 06/22/03 12:04 PM
Thom,- You would be the first to know if 240v was in direct contact inside your water heater.
Posted By: Thom Re: Electrocution Question - 06/22/03 01:25 PM
As wierd as this topic might be, for a hypothetical example and discussion:

If you lowered a heater into water and assuming that the wire contacts were not shorted with water (held out of the water) what do you think would happen? I believe that it would just heat the water. I am not talking about touching the unit directly.
Posted By: ga.sparky56 Re: Electrocution Question - 06/23/03 12:24 AM
The elements in a WH have a ceramic coating on them,thus the actual wire heating elements are not in direct contact with the water.

Russell

Actually they are imbedded in a ceramic with a metal coating,but still not in direct contact with the water.

[This message has been edited by ga.sparky56 (edited 06-22-2003).]
Posted By: DougW Re: Electrocution Question - 06/23/03 02:17 AM
I think a big factor is how much of the current passes through vital organs, and if you are in direct contact with a ground - electricity favors water over people.

(I'm not volunteering for a field test, however!)
Posted By: Big A Re: Electrocution Question - 06/23/03 04:15 PM
I always thought that this is the very reason for GFI's in bathrooms and kitchens. I also thought that the water became energized when the appliance "leaked" current through the conductive water to the grounded drain of the tub/sink. I also though that the amount of current draw was rarely enough to trip/blow the OCPD and that the person stayed energized long enough to arrest heartbeat and breathing. Kind of like wrapping you had around a pulsing electric fence. The shock is not enough to kill you but you can't let go, breath, or much of anything else until the pulse shuts off.
Posted By: ChrisO Re: Electrocution Question - 06/24/03 10:56 PM
Thom,- You would be the first to know if 240v was in direct contact inside your water heater.

There are what's called 'electrode' water heaters that use the water's resistance to heat it, neutral is bonded to the casing.

Chris
Posted By: John Steinke Re: Electrocution Question - 06/25/03 01:54 AM
Hollywood did a decent rendition of this in the movie "Groundhog Day."
Posted By: PCBelarge Re: Electrocution Question - 07/02/03 08:04 PM
At a grounding seminar given by Mike Holt, he wanted to prove what a poor conductor water 'CAN BE'. So he took the cord cap where the projector was plugged into the extension cord and placed it into a pitcher of water. Then he looked to make sure he was not grounded and he picked up the pitcher and drank from it.
The circumstances of whether or not you may be electrocuted in this situation have too many variables to take the chance it may not happen, just don't do it!

Pierre
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