The fire was made up of titanium, copper, and brass particles that had been built up in a dust collection system, and was started when a spark came in contact with these particles. The metal dust burns at such a higher temperature than wood that it can cause an explosion if water is used to extinguish it. These metals dusts were burning at between 1,800 and 2,000 degrees, whereas wood burns at about 450 degrees.
Luckily this plant is used to these metal dust fires occurring, and has a dry chemical powder to use for extinguishing these flames, and the local fire department knew not to attempt using water on the burning metal dust. Often this is not the case, or the metal dust is mixed in with other lower temperature combustibles, and the use of standard firefighting techniques ends up making the fire worse.
