Hi,

I guess there is a typo below, isn't it?

On Mon, 13 Sep 1999, Peter van Hoof wrote:

> http://www.bassengineering.com/electroc.htm
> The more serious electrocution and shock hazards occur above the let go
> limits. 99% of the female population have an let go limit above 6 milliamps,
> with an average of 10.5 milliamps. 99% of the male population have an let go
> limit above 9 milliamps, with an average of 15.5 milliamps. Prolonged
> exposure to 60 Hz. currents greater than 18 milliamps, across the chest
> causes the diaphragm to contract which prevents breathing and causes the
> victim to suffocate.  No data is available for females or children but
> suffocation is presumed to occur at a lower current level.
>
> The frequency of the electrical current is as important as magnitude when
> evaluating electrocution and electrical shock injuries.    Humans and
> animals are most susceptible to frequencies at 50 to 60 hertz. The internal
> frequency of the nerve signals controlling the heart is approximately 60
> hertz. Ventricular fibrillation occurs when 60 hertz current from the
> electric shock interferes with the natural rhythm of the heart. The heart
> loses its ability to pump and death quickly follows. Ventricular
> fibrillation can occur at current levels as low as 30 milliamps for a two
> year old child and 60 milliamps for adults. Most adults will go into
> ventricular fibrillation at hand to hand currents below 100 milliamps (0.1
> Amp).
>
> Humans are able to withstand 10 times more current at DC and at 1000 hertz
> than at 50 or 60 Hz.. Electro-Surgical equipment operating above 100,000
> Hertz pass high currents through the body with effect on the heart or
                                            ^^^^
rather "without", eh?!

> breathing of a patient. Do you think that Murphy's Law had anything to do
> with the American power line frequency being set at 60 Hertz and the
> frequency for the rest of the world being 50 hertz? All of the current
> limits referred to in this article are based on power line frequencies of 50
> or 60 hertz.
>
> http://www.vabch.com/stein/history.htm
> July 30, 1888 - Brown and his assistant Dr. Fred Peterson of Columbia show
> experimental results at the School of Mines at Columbia University by
> administering a series of DC shocks to a large Newfoundland mix dog. By
> 1,000 volts DC, the dog is agonized but not killed. Finally, Brown finishes
> the off with a charge of 330 volts AC. On a follow-up demonstration, SPCA
> steps in and second dog becomes first creature ever publicly reprieved from
> execution by electrocution (although it was later killed at another
> demonstration).
>
> Peter van Hoof
> -------------
> mailto:pvh@vertonet.com
> http://go.to/pvh
>
>