On Mar 23, 1:58*am, Dean Hoffman wrote:
On Mar 22, 11:32*am, Josh wrote:





On Mon, 22 Mar 2010 06:00:13 -0500, Dean Hoffman

wrote:
Josh wrote:

Yes, it's the current that kills (if enough of it passes through the
right path), but the voltage creates that current:

I (current) = V (voltage) / R (resistance)

The lower your skin/body resistance (wet skin has much lower
resistance than dry skin) or the higher the voltage, the higher the
current.

Lower voltages often aren't as dangerous for 2 reasons:

1) *Whatever your body's resistance, the current is lower

2) *The low voltage is often supplied by batteries or transformers
with lower current capacity (high internal resistance) -- if your body
tries to sink a lot of current (low body resistance), the voltage
drops significantly. * On the other hand, a car battery can supply
hundreds of amps at 12V, and you could easily electrocute yourself
with one if your body resistance/path is right.

Josh

* * You can, of course, *cite a few instances of people being
electrocuted with 12 VDC?

Of course not, this is Usenet!

Upon research, I'll retract most of that (especially the "easy" part)
and say that generally, 12V isn't considered enough to break the skin
resistance -- some references say 48V is required for *dry* skin, with
wet skin less but still not enough to kill. *I can buy that.

However, almost everything I've read is talking about *touching* the
terminals with your skin in the way -- if you punctured the skin
through to blood/other fluids, you create a much lower resistance path
that I believe could be deadly. *Imagine falling on the sharp edges of
the jumper cables, for instance. *I can't find reference to specific
instances, but I wouldn't chance it myself...

The bigger risk with a car battery is burns (shorting across a
ring/bracelet and a wrench) or explosion/acid burns.

Josh

* * *I've heard stories about burns caused by watch bands, *jewelry
and such. * It's always someone who heard about the guy
who..................... *Harry's is the first eye witness account
I've heard. * Mechanics I know don't wear anything metal on their
hands or arms.
* *I do irrigation wiring. *We can run anything under 30 volts (AC
usually) into a panel without going through a disconnecting means.- Hide quoted text -

- Show quoted text -

Come to think, I saw another accident with a battery. This guy
disconnected a battery from a charger without first turning the
charger off. (ie took the crocodile clips off the battery
terminals). There was an exposion that blew the top off the battery
and showered him with acid. He was wearing spectacles, so he was
fortunate, he didn't get any in his eyes. The electrical spark must
have ignited hydrogen gas. He didn't do that again! Heh! Heh!