cause of electrocution while welding ?

[henrym]

I have heard crazy stories about how RANDOMLY welders (or their plugs) can get wired up. maybe someone grounded that welder to the AC supply

sorry to hear about the accident.

[BearNPum]

Very unfortunate. I often wonder what it might take to have such an accident.

[BearNPum]

Question answered, I found the post a couple down from this one with other links as well. All is good.

"Do folks NEVER weld by setting the piece on a grounded table? I have done this, but it looks like it may have a down side."

[matteh99]

I do it all the time. It isn't any more dangerous than any other type of welding. The main thing is to make sure there is a good path for electricity from the work clamp to the electrode. If there is a good path between the electrode and work clamp the electricity will flow through the metal. If there isn't a good path the current will to find a alternate route, which could be your body. It will also be hard to actually get a good weld.

[D94r]

I didn't read extremely carefully, but saw a lot of numbers flying through these posts so please excuse me if I repeat something.

Half an amp will kill you. Or, when speaking as an engineer it's 500 milli amps, and that is enough to stop your heart.

Sounds as if the deceased somehow touched a live spot with one hand and grounded through the other. That explains the burns, and unfortunately had more than 500mA cross his body and through his heart. He somehow became a faster (or partially anyhow) ground than the material.

[arandall]

[quote=D94r;10831]I didn't read extremely carefully, but saw a lot of numbers flying through these posts so please excuse me if I repeat something.

Half an amp will kill you. Or, when speaking as an engineer it's 500 milli amps, and that is enough to stop your heart.


When I used to work in the power room of a telephone office, there were 48volt battery line-ups, with associated rectifiers each putting out about 12-1400amps. We were told that 1.5 milliamps directly through the heart would stop it. - That's why in those days, an experienced power room guy always kept one hand in his pocket unless absolutely necessary - and never wore jewelry - including steel rimmed glasses.

It's not the voltage that kills you - it's the current.

Cheers,
Art R.

[D94r]

Yup, thats why lightning victims often live. You can come across 1,000,000 volts, but with no amperage all you're going to do is feel pain.

I have seen a few different numbers as well for what will kill you. As I'm sure it will change slightly from person to person too. I've seen 500mA to 700mA as the absolute minimum for stopping the heart. 1.5 will definitely do that job in a heart beat.

Myth busters proved this, though their methods sometimes leave me screaming at the TV.

[arandall]

Yup, thats why lightning victims often live. You can come across 1,000,000 volts, but with no amperage all you're going to do is feel pain.

I have seen a few different numbers as well for what will kill you. As I'm sure it will change slightly from person to person too. I've seen 500mA to 700mA as the absolute minimum for stopping the heart. 1.5 will definitely do that job in a heart beat.

Myth busters proved this, though their methods sometimes leave me screaming at the TV.

Yeah - you're right about the mythbusters - but I still watch them every week!

Art R.

[matteh99]

It's not the voltage that kills you - it's the current.

There is a reason why you see danger high voltage signs and not danger high current signs. The high voltage sets up the potential for high current in a person.

You really need a bit of both.

A 6 or 12 volt lead acid battery can put out over 1000 amps but it would be hard to hurt yourself with it unless you drop it on your foot. The low voltage means you won't get much current through your body.

A shock from static electricity is high voltage but with very little current. So once again not that dangerous.

Eric

[jonesg]

Sad story, expect OSHA.
I watched the union electricians working on our power line, no messin around, cotton gloves first, then the big rubber ones.