Re: You use a utility transformer?!

To: tesla-at-pupman-dot-com
Subject: Re: You use a utility transformer?!
From: Mark Finnis <mefinnis-at-medicine.adelaide.edu.au> (by way of Terry Fritz <terryf-at-verinet-dot-com>)
Date: Wed, 09 Sep 1998 01:27:09 -0600
Approved: terryf-at-verinet-dot-com

At 07:57 PM 08/09/98 -0600, you wrote:

>It's not obvious to me that a distribution transformer would
>necessarily be more lethal than a neon sign transformer with equivalent
>voltage output.  Any current over a few mils, (passing through the
>chest) should be lethal in the long run .  I know there's a lot of data
>on morbidity vs time of exposure, but I think getting across a 15 kV 60
>ma NST (say between the hands) would have the same results as getting
>across a 15 kV, 100 kVA transformer.

I have been leaving this alone, but will now add 2c worth ......

Above is true and false.  If the transcardiac current is sufficient to
cause fibrillation (VF), you are dead.  OK, here the 60 mA NST is as lethal
as the pig.  If you consider the current actually required to produce VF
with intravascular catheters it is about *** 0.1 mA ***

(interesting sub-note .... the required current for fibrillation is at a
minimum at 50 hz .... very unfortunate design that !!!)

Now lets assume you are lucky.  Lets say there is a buddy helping who knows
CPR and he starts, the paramedics arrive, defibrillate you and you live to
die another day.....

1.  The silly bastard who touched the NST has a small burn on the hand, a
few broken ribs from over-enthusiastic CPR by his "friend", a couple of
burns on the chest 'cause the bloody paramedics never seem to be able to
get the paddles over the conductive gel plates and feels generally a little
shook-up (medical term, that).

2.  The fellow with an apparent disrespect for pigs has ....... 30-40% full
thickness skin burns from the flash (6-10 weeks hospitalization and >30%
late mortality), a deep muscle compartment syndrome requiring amputation of
the arm from muscle destruction, and depending upon the "exit-point" ....
possibly a second limb in danger of going in the bucket, combined with
other deep tissue injuries.  Plus ... all of the above from the helpful
bystanders.

Both CAN kill you.  One however is not current limited and can result in
massive tissue destruction, such that any reasonable chance of functional
recovery is absent.

Motto:  Remember the film "Babe" ........ be nice to the little pig !!!!!!!!

Please take me seriously ......

__________________________________________________________________
Mark Finnis					Hm:  61 8 8289 5205
Consultant, Intensive Care Unit			Wk:  61 8 8222 5042
Royal Adelaide Hospital				Fax: 61 8 8223 6340
Adelaide  SA  5000,   Australia			Mbl: 041 2324268
http://www.health.adelaide.edu.au/icu/
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