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Reminds me of the time I turned myself into a Van de Graff generator at work.

I was a theater projectionist, back when you had 20 minute reels you had to constantly change, while babysitting two high-voltage, water-cooled, carbon arc projectors. Sometimes the film would break and you’d have to splice it. So when the theater got a print in, you had to count and log the number of splices for each reel, then the next theater would do the same and retire the print when it got too spliced up (plus, sometimes if it was the last night of a run, some lazy projectionists would splice it in place with masking tape and then you’d have to fix it). Sometimes you had to splice in new trailers or remove inappropriate ones as well.

Anyway, you counted splices by rapidly winding through the reel with a benchtop motor with a speed control belted to a takeup reel while the source spun freely. Then, while letting the film slide between your fingers, counting each “bump” you felt as it wound through. I was told to ground myself by touching the metal switch plate of the speed control knob with my other hand. One night I forgot and let go until my hair started rising. I’d gone through most of the reel at a very high speed and acquired its charge.

I reached for the switch plate and shot an 8-10” arcing discharge between the plate and my fingers.

Lesson learned, I held the switch plate from then on.



I worked in a casino that had a wool carpet. When the carpet was new it was ridiculous the amount of static that it generated on you. I was wearing steel toe non slip and anti shock shoes too!

I quickly learned to hold my machine keys ring (3 inch wide ring) and tap it to the slot machine frame. Often a three inch violet spark would jump and I could even feel my clothes move. One time I even causing one of the slot machine player tracking system to reboot, it was that or me better it got the hit.

A manager said at a casino they used to work at they would spray fabric softener on the rugs to alleviate static. I don't know if it worked or not.


I lived in an area with extremely dry winters (dew points below -40). My bedroom was carpeted. Some mornings I would reach for the light switch and see a 2" bolt of white pain jump off my finger. It was like a strobe light. I learned to touch light switches with my elbow. Same bolt but less painful to take it on the elbow.


I learned to touch things with a metal object like a key, so the charge spreads out across the part of skin holding the object and the pain is less.



The Daresbury Laboratory in the UK had a giant Van de Graaff generator housed in a high concrete tower. I remember staying on site and waking up in the middle of the night with a really creepy feeling that turned out to be caused by that thing operating.


The tower is empty now, there is a good view from the top floor though.


Did you finish your shift that night? (Some 2cm arc from an electric fence brought me to my knees one time.)


@idiotsecant is correct. Length of arc correlates to voltage, while most of the potential pain or damage from an arc will correlate more to amperage and/or to duration.


You're correct, but just for fun's sake:

The amperage of static elecricity discharges like this can be quite high, tens of amps is common.

So walking across a carpet and getting a shock can easily be tens of amps at thousands of volts, and we're just totally fine (because it's for a tiny fraction of a second).


So it's not the Amps that get you, but the Coulombs? Or is it the Joules?


Lethality of electricity is multi-dimensional, trying to reduce it to a single quantity does not really work (exposure time and electrical frequency are very important).


neither. even a shortcut saying like "total energy delivered" is not accurate, because it depends on how it is delivered and how it dissipates.

styropyro made a fascinating (if terrifying) video about it


Sounds a bit like fuse wire (except the frequency dependence)... There's both a current and a time component. High overloads can be tolerated for a very short time without blowing the fuse, while low overloads can be sustained for longer before the fuse reaches its maximum temperature and breaks.


It also matters where the arc lands. I leant over an electric fence (whim I thought was off) wearing wet swimming shorts to fetch a ball, once.

Never, ever again.


You had less voltage, but whole lots more current than parent post.




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