Valerie Weihman posted the following to the mailing list and I thought there was too much valuable information there to let it slip away unnoticed. I'm posting her response to a question here. What I would like to know has anyone experienced or know of similar experiences with welding machines exhibiting such a detrimental behavior. After any injury with a machine, the machine should be locked out until it has been checked out and the situation rectified.
Electrical shocks happen in welding when the person becomes a better ground than the ground cable.
The machine must be grounded as well as having a electrode cable and a ground cable. Obviously, standing in a bucket of water with your feet soaked makes you a better ground. Some machines are water cooled - make sure there are no leaks. Because you mention that this is a TIG welder - there are certain concerns with TIG welding. The cycles involve the electrons going one direction and then turning around and going the opposite direction.