[guandi]

Where i work is two doors down from a car body shop, and i would like to tell you a story about a guy called James who used to work there.

James did welding on chassis frames, heavy panels and would make you a damn fine workbench for £80 in just 2 hours. he used a propane cutting torch (not as effective as acetelyne, but far cheaper), and a propane welding torch for many years, and was very proffecient and most of all *safe* with them.

He was a bit of a prankster, and used to love filling latex gloves with propane, and setting fire to them, small fireball, everyone laughs. one day James wasnt there and one of his coworkers wanted to show a new employee the trick with the latex glove and propane. what he did however was use the gas torch how it had been set up, with a oxy-propane mix... and when he ignited the glove, the oxygen accelerated the explosion so much the fireball was nearly 20ft wide and ended up giving four people 1st degree burns.

When James was told about the accident he made a lockable cupboard to keep the propane and oxygen bottles in and he was the only person with a key, but when he went on holiday for 2 weeks last year he was told to leave them the key in case anyone had to do any welding, he did and he regretted it. about half way through his holiday he recieved a phone call that there had been an explosion in the body shop and that even tho no-one was killed, 2 people who were working late next door were injured from flying glass and one would be deaf for life.

It turned out that the same guy that did the bad glove trick had used the torch and bottles just a day after James left, and did not turn off the valves on the bottles, and gradually the cupboard filled with gas. a few days later the gas concentration in the cupboard was so high, that when the ringer for the office phone went off, a spark arced between it and the cupboard (about 4cm) and it blew up.

the moral of this story is, that propane is *very* dangerouse in some places, and not so in others. think about having a computer case, essentually a metal box filled with an explosive gas, and then a spark from the computer or the compressor or fan kicking in on cyclic systems.... bang.