The AviVest remains inflated for some time after you inflate it. It does not deflate after 2 minutes. It should remain inflated long enough for you to get out of the mountains.
When you first inflate the AviVest it is quite tight, and over the course of 10 minutes or so you might notice the air bag lose some of this initial tightness, but your AviVest should provide you with avalanche protection for an additional hour or more.
Here's why. When the initial 3 pounds of pressure per square inch starts working on the welded nylon seams, the release valve (the small valve you push to deflate the AviVest), and other parts of the system there is a minute or two of the forces trying to equalize. There is also the effect of the cold outside air temperature starting to work to condense the gas inside the air bag slightly.
The result is that the air bag may lose some of the initial tightness, but remain inflated and work properly.
When we do our testing of the AviVest we usually inflate the AviVest just prior to hooking the dummies on the helicopter long line. The chopper has to drop the dummies on the mountain, land to remove doors and load the bombs used to create the slide, fly back to the mountain to drop the load, and get into position to film the test. All of this takes at least 20 minutes, and only then do we do our testing. And after all of this time the AviVests float to the surface.
We have done testing in the past with partially inflated air bags and they too brought our test dummies to the surface of an avalanche.
