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Safety training..



Original poster: "Jim Lux" <jimlux-at-earthlink-dot-net> 

An interesting issue has come up at work, and I think the folks on this list
will have valuable insights.  You can send them to me off list if you like,
but they might be interesting to the whole list.

Here's the deal..

At work (Jet Propulsion Lab), we work with a variety of high power RF
sources (usually microwave, but also HF). We've got a whole herd of young,
bright engineers working on things like this that have never had HV
experience.  Unlike myself and my contemporaries (and, probably, most of the
people on this list), they have not had that "fundamental life changing
experience" of getting shocked as a youth, and as a result, do not (in my
opinion) have adequate respect for the "get close and it will reach out and
kill you" nature of these things.

One older engineer commented that when he started working at a large
company, one of the senior engineers had taken him down into the lab where
they were doing high power modulators and showed him these two foot marks
burned into the tile floor.  They were from someone who had reached into a
piece of equipment that he had thought was safe, but wasn't.

My group supervisor had an experience as a 10 year old plugging zip cord
into the wall socket to measure the voltage on a panel meter he was holding
in his hand (in 220V land!).

A good friend of mine who knew nothing about electronics had a life changing
experience when I suggested that the 300 W tabletop plasma etcher he was
cleaning might have significant stored energy, and that he should think
about shorting the caps out before working on it. (I walked out of the room
to my office, heard a very loud bang, and saw my friend holding a
screwdriver with an amazingly large chunk knocked out if it, and very, very
wide eyes.  Quote: "And I had my hand in there before you came in the
room!")

I had more zaps that I care to remember as a kid standing in bare feet in
the garage working on low voltage power supplies, but being careless about
the 110V wiring.  To this day, I don't even reach into TTL circuitry with
both hands.


All of us 40 and olders have similar experiences... the 30 and unders do
not.  They haven't had that "oh my gosh, I could have died" experience.

So... here's the's question. How can we come up with some sort of suitably
visceral training.  When I started working with really HV (50 kV+), an old
guy (always a good sign in HV workers) suggested that I get a big Van
deGraaff and fool with it.  No kidding... you get within a meter and the
hair literally stands up on your arm and you get zapped a couple times when
you don't expect it..  Less than a joule, but it stings, and you remember
it.

At work, it's even more insidious, because we're working with high power
microwaves (although the 1kV, 10 Amp supply for the HF amplifier gives me
the willies, but unfortunately, it doesn't do the same for the young
engineer working with it) which you can't see, or feel, until it's too late
(no evil hiss of corona, etc.).  That whole, oops the waveguide flange
wasn't tightened, etc. kind of thing. (or the, don't look into the open
waveguide with your remaining good eye, thing).

What I'm looking for is good ways to give people that "if I'm not careful,
I, or someone else, will die" feeling.