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Fire Burns Differently In Space
New submitter black6host writes with this interesting snippet from Space.com: "NASA is playing with fire on the International Space Station — literally. Since March 2009, the space agency's Flame Extinguishment Experiment, or FLEX, has conducted more than 200 tests to better understand how fire behaves in microgravity, which is still not well understood. The research could lead to improved fire suppression systems aboard future spaceships, and it could also have practical benefits here on Earth, scientists said."
relevant: http://www.youtube.com/watch?v=iSqOqRACxUM (fire at the MIR station)
That's a nice notion. However, there's a wicked problem with the bends. People say "your blood will boil", but that's not actually what happens; the bubbles will be dissolved gasses coming out of solution. even if you go with a straight oxygen environment (which we learned was a "bad idea" in the Apollo program), the oxygen dissolved in the astronaut's blood will come out of solution. Unfortunately, it won't dissolve again very quickly, which will leave you with bubbles in bad places, like the brain and lungs.
You're also making the assumption that you have enough stored gas (call it air) to repressurize the spacecraft. Even if you live through the depressurization and repressurization, you haven't addressed the source of the fire, which will likely re-ignite. As long as spacecraft are small, gold-plated things, designing to current fire specs is a given. However, as they evolve into large vehicles, designing fire-proofing into everythign will become less and less feasible. People will want to bring clothes and food and shit like that.
The other major thing to be considered is that while droplets behave differently, we also haven't looked at explosive combustion. I suspect it will be very similar. However, we might find that it's very different. Right now we cover military pilots in polyaramids, and accept that paying passengers are probably going to die in a flash fire. The assumption behind the flight suit is that the pilot's on an O2 mask, and so the lungs will be protected. Flash fires might behave very differently, and fire is a complex, complex beast.
I've lived through a fire in an airplane, and it's scarry as fuck. Fortuantely, the aerospace community is very aware of it and designs against it.