In the event of an avalanche, the user must tug on the handle to trigger the release of gas from the high-pressure cartridge: this inflates the 150-litre avalanche airbag within 3 seconds.
The airbag concept is based on the physical principle of inverse segregation. This is a phenomenon whereby, given a uniformly moving mass of particles, the smaller particles sink downwards and the larger ones float to the surface. The inflated airbag increases the victim’s volume and greatly amplifies this inverse segregation effect. The avalanche backpack helps prevent total burial in the snow. It also keeps the victim’s head on the surface, and its bright colour aids rapid localisation.