Re: Van de Graaff generator safety question (fwd)

[Steven Roys <sroys@xxxxxxxx>]

---------- Forwarded message ----------
Date: Sat, 27 Dec 2003 11:54:58 +0100
From: Finn Hammer <f-h@xxxx>
To: High Voltage list <hvlist@xxxxxxxxxx>
Subject: Re: Van de Graaff generator safety question (fwd)

All,

I like to make a bit of buisness out of this hobby, and am constantly
preparing my main coustomer, The Danish Electricity Museum, to order a
proper VDG.
They have reservations, because of this incident:
Using one of the Science First VDG`s, which is advertised to deliver
400kV, they charged school children up to as much as they would reach,
to see if their hair would stand on end.
One of the children, a girl, wore a knitted sweater, which contained a
minor amount of metal or metalized plastic in the yarn, for sparkling
effect. It appeared that this network of metallic threads held a charge.

After the discharge of the machine, during which the kids still touched
the machine, the operator would also strike over the kids clothing with
the grounded stick, to remove any extra charge.

When they discharged the girl`s sweater, the stick drew a long arc, and
the girl was subject to severe discomfort.

To look out for metalized yarn in a sweater is One of those reservations
that are hard to arrive at by speculation.

Merry christmas, and cheers,  Finn Hammer



High Voltage list wrote:
> Original poster: Steven Roys <sroys@xxxxxxxx>
>
>
>
> ---------- Forwarded message ----------
> Date: Fri, 26 Dec 2003 09:46:40 -0700
> From: Gomez <gomez@xxxxxxxxxxxx>
> To: High Voltage list <hvlist@xxxxxxxxxx>
> Subject: Re: Van de Graaff generator safety question (fwd)
>
> On Friday, December 26, 2003, at 07:39  AM, High Voltage list wrote:
>
>
>>---------- Forwarded message ----------
>>Date: Fri, 26 Dec 2003 11:19:24 -0000
>>From: colin.heath4 <colin.heath4@xxxxxxxxxxxx>
>>To: High Voltage list <hvlist@xxxxxxxxxx>
>>Subject: Re: Van de Graaff generator safety question (fwd)
>>
>>hi terry,
>>            i havent done a great deal with van de graaff generators
>>but
>>have used one this size. poss bigger. i have drawn the sparks to a
>>hand held
>>metal object while stood on the floor. i cant say wether its safe but
>>get to
>>about a foot long it starts to hurt a bit! i also witnessed someone
>>get what
>>you said to the forehead and they are still ok.sorry not to give more
>>theoretical answers just thought i would share what i have seen done
>>cheers
>>colin heath
>
>
>   I think it would be risky for us to judge the safety of a particular
> practice
> on anecdotal information alone.  People have been hit by lightning and
> lived,
> others have been hit by lightning and died.  People have been bit by
> wall juice
> and lived, others have died.  There are simply too many variables where
> electrocution
> hazards are concerned, to say "this or that is definitely safe or
> unsafe".
>
>   If you want my advice, I would go ahead and build it (I mean, hey, I
> can't be a
> hypocrite here, I am going to build one too, eventually), but plan your
> demonstrations
> and discharge electrode(s) such that friends, family, pets, antique
> electronic
> calculators, etc, will not take hits.  Your enemies on the other
> hand... :D
>
>   - Gomez
>
> ...........................................................
> The problem with using bleeding edge technology is that the
> blood that winds up on the floor is usually your own.
>
>
>