The Avalanche Terrain Risk Scale (ATRS)

The Avalanche Terrain Risk Scale (ATRS) can be to classify the risk associated with an avalanche.

Parameters:

(1) burial potential

(2) injury potential

(3) rescue chances

(4) starting zone

(5) vertical drop (height of mountain side involved)

(6) destructive forces

(7) injurious terrain features (trees, rock outcroppings, cliffs, etc.)

(8) deposition area for beacon search

Parameters	Class 1	Class 2	Class 3
burial potential	shallow burial	shallow burial	possible deep burial
injury potential	no injury	mild injury	moderate injury
rescue	self rescue probable	probable	questionable
starting zone	small	small	moderate
vertical drop	< 15 meters	15 - 50 meters	50 - 100 meters
destructive forces	minimal	small	moderate
terrain features	none	none	none
deposition area	small with consistent runout	small with gradual, consistent runout	moderate with abrupt transition

Parameters	Class 4	Class 5
burial potential	deep burial	deep burial
injury potential	severe injury	severe injury and/or death
rescue	doubtful	highly improbable
starting zone	large	large or multiple at various elevations
vertical drop	> 100 meters	mountainside
destructive forces	large	potentially devastating
terrain features	<= 50% of slope potentially injurious	> 50% of slope potentially injurious
deposition area	large	very large or multiple

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