The AvaLung TM was developed in 1996 by Thomas Crowley and Black Diamond Equipment Ltd. in Salt Lake City, UT, USA (17). The device is built into a vest or harness, worn over the torso when travelling in areas that are not controlled for avalanches. If an avalanche is triggered the user must put the mouthpiece in the mouth and breathe through it while buried. A one-way valve allows inhalation from the surrounding snow and exhalation to the rear of the vest. This provides an artificial air pocket and avoids a build-up of carbon dioxide in the inspired air.

From 33 successful tests so far, one can conclude that a completely buried person can survive with the device for up to an hour. So far, a few burials with AvaLungTM have been documented in which the victim survived. However, the International Commission for Mountain Emergency Medicine does not yet recommend using this "rescue vest.” (18) Additional cases are needed for a definitive assessment.

It remains doubtful, primarily, how many of those wearing the AvaLung will be able to position the mouthpiece correctly in an emergency.

The most serious disadvantage of this system is the fact that use of the AvaLungTM implies acceptance of a complete burial with all its risks. Timely rescue, even with a prolonged period of survival cannot be guaranteed.