Avalanches are enormously dangerous. In the sixteen year period ending in 2001 over 82% of fatalities in avalanches were during recreational activity: skiing, climbing, snowboarding or snowmobiling.
The majority of victims that are buried are still alive. Little time is available to rescue buried victims, off-piste skiers carry avalanche equipment for this reason: the best chance of survival is for your buddy to dig you out. People die quickly buried in snow: research shows that in only half an hour chances of survival are decreased to 50%.
It is a backpack that, when triggered by the victim, creates enough steam. This melts the snow creating a cavity giving life saving breathing-space. If it works it should dramatically increase the chances of survival of buried skiiers and boarders.