D
Don Klipstein
In said:You are correct; 100ma is about the lethal threashold. But it is difficult
to get 100ma off 120v unless you are in saltwater.
Naturally adverse medical conditions, or just plain bad luck, will change
everything!
A few problems with this:
1. Perspiration is salty. A sweaty hand on a metal power tool could have
resistance down to about 1k ohms or so.
2. Electric shock can stimulate sweat glands.
3. Electric shock at a few 10's of mA or maybe around 10 mA can stimulate
muscles and cause you to involuntarily grip what is shocking you.
4. Most sources say 100-1,000 mA is a range of current that is likely to
cause ventricular fibrillation, with a few saying this deadly range
starts at 50 mA. (Also a few sources make the upper limit of this
"most deadly range" lower.)
The changes of death do not decrease to zero at 99 or 49 mA. I have
heard of electrocution by 30 mA from a neon sign transformer, although
people *usually* survive this.
5. Electrocution is unreliable. With electric chairs, they use enough
current to either:
* Cook vital organs
* Paralyze breathing muscles long enough to deprive the brain of
oxygen to the point that breathing will not restart when the
shock ends
Lack of electrocution is simularly unreliable.
6. The low fatality rate of 110-120V shocks lulls people into a false
sense of security that leads to this voltage achieving a body count.
On US Navy ships, most power circuits are 440V rather than 110V, and
most electrocution deaths are from 110V. (Another factor could be
that lights and ordinary outlets - where exposure to less-trained
people is greater than that of 440V stuff - are 110V.) (Yes, US
Navy ships have 110V at least nominally rather than 120V.)
- Don Klipstein ([email protected])