NASA does not have to imagine the consequences of fire in space. As a partner in Russia's Mir space station 12 years ago, the space agency got first-hand experience when a faulty oxygen candle exploded in flames, filling the outpost with thick smoke and blocking half the crew from reaching their lifeboat.
"I did not expect smoke to spread so quickly," NASA astronaut Jerry Linenger, who was aboard Mir as part of a U.S.-Russian astronaut exchange program, recalled after his return to Earth.
"(It) was about 10 times faster than I would expect a fire to spread on a space station," he said.
NASA hopes any future space fires will be safely contained in experiment boxes. But it isn't counting on that. With a new spaceship under development, the agency is investing in next-generation fire-fighting gear that is specially designed to work in microgravity.
"In space, fires are like spheres. They're not shaped like what we have on Earth," said James Butz, vice president of operations for Colorado-based ADA Technologies, which last week announced it had received a grant worth nearly $100,000 from NASA to continue work on an extinguisher that coats fires in a fine mist.
The technology is one of two NASA is exploring for use aboard its Orion spacecraft, the follow-on program to the space shuttle. The agency plans to retire the shuttle fleet in 2010 and develop capsule-style ships that can travel to and from the moon.
"There are mainly three emergencies that we train for — a fire, a depressurization, or if the atmosphere becomes not livable," said Sandra Magnus, who returned last week from a four-month stay on the International Space Station. "If the situation can't be contained, we basically train to evacuate."
Astronauts aboard Orion will not have that luxury.
Slideshow: Month in Space: April 2013 ADA's technology would coat a flame in tiny droplets of mist, much like fog, Butz explained.
The key to getting the droplets small enough is to use compressed gas. The system uses water and nitrogen so it is environmentally non-toxic and has an unlimited shelf life. Also, because oxygen and nitrogen will be aboard the spacecraft, the extinguisher can be refilled if needed.
The technology, which has been under development for about a decade, caught NASA's eye about two and a half years ago. The company's most recent grant is intended to tweak the nozzle design to address issues raised by the surface tension of water droplets.
The other fire-fighting technology under development is a water foam, which Butz says works well, but is messy in microgravity.
"The stuff can go everywhere," he said.
© 2012 Discovery Channel