Avalanche Hazard Scale

Risk level 1 Snow layers are generally very stable.
Avalanches are unlikely except when heavy loads** are applied on a very few extreme steep slopes. Any spontaneous avalanches will be minor sloughs. In general, safe conditions.
Risk level 2 On some steep slopes* the snow is only moderately stable. Elsewhere it is very stable.
Avalanches may be triggered when heavy loads** are applied, especially on a few generally identified steep slopes. Large spontaneous avalanches are not expected.
Risk level 3 On many steep slopes* the snow is only moderately or weakly stable.
Avalanches may be triggered on many slopes even if only light loads** are applied. On some steeper slopes*, medium or even fairly large spontaneous avalanches may occur.
Risk level 4 On most steep slopes the snow is not stable.
Avalanches are likely to be triggered on many slopes even if only light loads** are applied. In some places, many medium or sometimes large spontaneous avalanches are likely.
Risk level 5 The snow layer is generally very unstable.
Even on gentle slopes, many large spontaneous avalanches are likely to occur.

Further Explanation:

* Avalanche-prone areas are defined exactly in the detailed avalanche hazard report (altitude, inclination, exposure, type of terrain):

  • Moderately steep terrain: slopes less steep than 30 degrees <
  • Steep slopes: steeper than 30 degrees
  • Extremely steep terrain: in combination with unfavorable inclination (steeper than 40 degrees), type of terrain, vicinity to mountain ridges, roughness of terrain

** Additional load:

  • low: a single skier / snowboarder / rider, riding gently without falling; snowshoe hikers; groups keeping enough distance (>10m)
  • high: two or more skiers / snowboarder / riders without keeping enough distance; snow-grooming machine; blasting; single walkers / alpinists

More detailed information and descriptions in German are available at www.lawinen.org

Source: lawine.gv.at