A technology used by NASA to protect crews working around hazardous gases soon could soon become part of a number of life-saving applications for those venturing both far beneath and above the Earths' surface, the agency announced.
The Cryogenic Refuge Alternative Supply System (CryoRASS) and a smaller liquid air-filled backpack currently under development in Kennedy Space Center's Biomedical Lab could store more than twice the amount of breathable air than traditional compressed gas systems.
Funded by the National Institute for Occupational Safety and Health (NIOSH), such devices could change, for example, the way coal miners seek refuge or flee from underground disasters.
"We're excited about this cryogenic technology because it has the potential to save lives and improve safety in mines," David Bush, lead NASA engineer, said in a press release. "Currently mines use big tube banks of compressed air with no cooling. Our solution uses smaller, lower pressure dewars of liquid air with cooling."
The way CryoRASS and the backpack, called CryoBA, work is by drawing air into a closed environment, then vaporizing and circulating it back to the user - a system Bush has nicknamed "passive air conditioners."
All told, initial demos show a drop in temperature by about 15 degrees, and since many refuge chambers stand no more than 30 inches tall, cooling would likely be a welcome feature.
"When you get about 10 men in a small confined space, essentially laying down in tin cans, with their body heat, it can get really hot in there," Bush said.
Another advantage to the liquid air systems is that it is safer than current devices.
"Compressed air has its own hazards because it's stored at a high pressure. It's also heavy and takes up a lot of space," Bush said, adding that compressed 100 percent oxygen can pose possible fire hazards.
Another plan being discussed is that of refill stations in mines spaced about 90 minutes apart, so that crews could walk out of a disaster situation with their personal CryoBA backpacks.
"NIOSH asked us to develop prototypes that we will test to their standards," Bush said. "The idea is that once we successfully test them, we can demonstrate the technology to commercial life-support providers for use in other applications, such as firefighting and military rescue operations."
Such technological advancements, meanwhile, have not gone unnoticed by the agency's newest human spaceflight programs, for which Bush says they could also prove relevant.
"In an emergency situation, rescue crews will have to go up some sort of launch structure, pull a crew out of a confined capsule, and get them to safety all within the span of their breathing device," Bush said. "We did a rescue dry run with a mock Orion capsule and, because the entryway is small, having a device with a smaller profile that is more efficient with the weight-to-space ratio is helpful."