"Only a lot of luck will save some of the victim’s lives...
An avalanche consists of different particles of snow. Those particles move underneath each body and push it to the surface by rotating until the avalanche slows down. This fact and the change of direction of the avalanche are the reason why approximately half of all avalanche victims end up on top of the avalanche.
... others die in the avalanche.
A completely different scenario exists for those who do not end up on the surface of the avalanche. Once the avalanche slows down, rotation and lifting abilities also slow down. The victim cannot reach the surface anymore due to the higher density and lesser volume. In most cases this burial is deadly.
With the ABS you have 150 liters more volume ...
Once activated, the ABS equalizes the volume and density of the victim relative to the surrounding snow by working on the principle of "inverse particles" .
...and you are ontop within 2 seconds.
As with a life vest in the water, the victims swims on the surface of the avalanche. The added volume of 150 liters has been calculated to be needed for cold, dry and loose snow. If the snow is denser, wetter and heavier less volume is needed. The statistics show that all victims carried down by a moving avalanche stayed on top and survived the incident."
This was taken from:
http://www.abssystem.com/ 
