This story brought to you by the letter “learn some damned chemistry before you go spraying water on a metal fire, dumbass!”
http://www.google.com/hostednews/ap/article/ALeqM5hpkiJxWwn1nPeOffnH7m3xhhHqkwD9GUTOAG0
Explosions and fire tore through a block of industrial buildings in South Los Angeles early Wednesday, hurling shrapnel and fist-sized chunks of molten titanium that injured three firefighters.
The metal was inside a company that manufactures titanium golf clubs and it “rained down in a huge fireball of sparks and burning shavings,” Fire Department Battalion Chief Mario Rueda said. “It was unbelievable.”
…
Titanium stacked inside one building exploded when it was hit with water from fire hoses, Rueda said.
Well, DUH.
And the author of the article goes out of his way to display his ignorance of basic science:
Burning titanium creates its own oxygen that feeds the flames, Rueda said.
(Yes, yes, he’s quoting the clearly ignorant fire chief, but he does not correct the statement.)
For those of you who don’t know (and if you don’t, I really hope you’re not a firefighter), titanium when it burns does not “create its own oxygen.” That would probably require some sort of nuclear fusion process. What it does do is burn like magnesium: white hot and angry. Burns like any other fuel… combusts with the oxygen in the air to form titanium oxide.
What titanium looks like when it burns. Don’t look too close… the bright light and UV will blind you.
Magnesium, titanium and other burnable metals become entertaining when some dumbass sprays water on ’em. The metal fire is hot enough that it actually strips the hydrogen off the oxygen in the water molecule, and then combusts with the oxygen… leaving the superheated hydrogen to float upwards to where it can find free oxygen, at which point the hydrogen now does the little combustion dance.
So if you have a titanium fire, do *not* spray water on it.
There are two basic ways to deal with a titanium fire:
1) Cover it with sand, dirt or salt. These are generally non-combustible and will melt, covering the metal with molten glass or molten salt, sheilding it from oxygen. Fire goes out. *Days* later, after things have cooled down (and not before), you can go in and try to make sense of the mess.
2) Run away. Call your insurance company and write off your losses.
#2 there is the sane choice.
Either the firefighter here were criminally ignorant/negligent, or they were mis/under-informed regarding the contents of the facility.
NOTE: if you think you might have a metal fire, and actually think you might want to try to put it out, you need to get a “Class D” fire extinguisher. Expensive, heavy as hell, shoots out not water or carbon dioxide (NOTE: burning metals will happily tear the CO2 molecule to shreds and dine on the oxygen, so don’t use one of those, either), but salt, sand, copper powder, graphite, a few others. There are apparently a few water-based solutions which can be used with titanium, but these are specialty substances, not tap water. Each metal requires a different type of Class D extinguisher. Having seen a few in action (just demonstrations, not, fortunately, on actual fires), they don’t shoot the salt out, they just sort of barf it out. So you have to be right on top of the fire.
Most titanium alloys are pretty fire resistant… you can weld ’em, grind ’em (producing a shower of white – not yellow – sparks), zap ’em with lasers, and the most they’ll do is melt. But pure titanium is reasonably bad news, and pretty much any titanium alloy *will* combust if you get it hot enough, and then supply enough oxidizer.
