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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."
I would think that the worst possible thing (or best possible thing, from Invader Zim's viewpoint) that could happen with a fire in zero G is air flow / turbulence. If there isn't any movement of air, then the oxygen surrounding the fire is consumed and the fire burns very slowly. Since convection currents are a product of gravity, they don't occur in zero G so no fresh O2 is sucked into the fire for combustion as it does here on earth. So I would think anywhere there is an air vent blowing air, or even people just moving around in the environment, you'd have blowtorch like fire forming where the air is disturbed. I bet you could literally see the turbulence in the air as wisps of flame. Kind of disturbing to think of.
An example of this is in a swimming pool. Have you noticed that if you hold very still in motionless, cold water, that you will begin to feel warmer, but as soon as you move it feels cold again (and no, I'm not talking about heating the pool with your pee). That is because the molecules closest to your body heat up, and since they aren't flowing and being replaced by colder molecules, only conduction takes heat away. It's sort of the same principle with fire in zero-g, where the fuel has consumed the oxygen near it (and it is also surrounded by combustion byproducts as well), so as long as fresh air isn't wafted into it, combustion almost grinds to a halt.
Better known as 318230.
It's not as totally and completely insane as it sounds. Generally, people will recover from exposure to vacuum on their own if the exposure is short (less than 30s) and with surprisingly minor injuries if exposure is less than 90s. And that's without training and a warning of what's going to happen, given proper planning and equipment I suspect you could push the survival rate to the high 90%s, maybe even to two 9's.
Given the choice between burning to death in inescapable zero-g fire and an automated 15 second emergency purge, with a quick re-pressurization system, O2 masks for quicker recovery, and the ability to manage air pressure afterwards to treat the bends... personally, I'd give it a shot. The only real question mark is if the source of the fire has been taken care of. If it's an ongoing short you might find yourself in the same boat you started in, but even that could be addressed by re-pressurizing the spacecraft with nitrogen and relying on O2 masks for the crew until everything is straightened out.