Western Massachusetts laser cutting machine factory fire

A $2–3M oxygen-assist laser cutting machine running lights-out in a Western Massachusetts factory caught fire and was destroyed. The plaintiffs hypothesized that metal-powder accumulation under the machine ignited. Tom (called in after another fire investigator) noted that with oxygen-assist cutting, the powders are already iron oxide — "you can't burn wood twice." Plaintiffs withdrew the suit at mediation.

I had a situation out here in Western Massachusetts. One of these machines might cost two or three million dollars, and you can run them lights out in the factory. You program them, the sheet is fed in, you turn off the lights and tell it what to do all night. You come back the next morning, you've got thousands of parts sitting there. One of these machines caught fire in the middle of the night in a lights-out factory and destroyed the million-dollar machine. People looked at the remains for three days and couldn't find the ignition source. The people who wanted to sue the company that made it, to get their money back on their messed-up machine, said okay, we think it was the metal powder that ignited. Very finely divided metal powder has a lot of surface area, and if it gets hot enough it can ignite.