Roughkype, another thing they probably didn't tell you is that the damage from shocks to your nervous system in general and your heart in particular is cumulative, that is it builds up over time without ever completely healing and gets a little worse with each successive shock. It's one of the reasons I'm moving from my trade into IT, since I've had a couple of ripper shocks. Some were clearly my fault, some less so, but I could have prevented all of them if I'd been pedantic about isolation instead of allowing myself to be intimidated into do "what was best for the production line". Sometimes the line just has to stop and the production foreman just has to suck it up or whatever needs to be done, doesn't get done.