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D E F I

European Danger Scale with recommendations

Danger level Icon Snowpack stability Avalanche triggering probability Consequences for transportation routes and settlements / recommendations Consequences for persons outside secured zones / recommendations
1 low gs1 The snowpack is generally well bonded and stable. Triggering is generally possible only with high additional loads 2 on very few extreme slopes. Only natural sluffs and small avalanches are possible. No danger. Generally safe conditions.
2 moderate gs2 The snowpack is only moderately well bonded on some steep slopes 1, otherwise it is generally well bonded. Triggering is possible, particularly through high additional loads 2, mainly on steep slopes indicated in the bulletin. Large natural avalanches are not expected. Low danger of natural avalanches. Mostly favourable conditions. Careful route selection, especially on steep slopes of indicated aspects and altitude zones.
3 considerable gs3 The snowpack is moderately to weakly bonded on many steep slopes 1. Triggering is possible, even through low additional loads 2 mainly on steep slopes indicated in the bulletin. In certain conditions, some medium and occasionally large natural avalanches are possible. Isolated exposed sectors are endangered.Some safety measures recommended in those places. Partially unfavourable conditions.Experience in the assessment of avalanche danger is required. Steep slopes of indicated aspects and altitude zones should be avoided if possible.
4 high gs4_5 The snowpack is weakly bonded on most steep slopes 1. Triggering is probable even through low additional loads 2 on many steep slopes. In certain conditions, many medium and multiple large natural avalanches are expected. Many exposed sectors are endangered. Safety measures recommended in those places. Unfavourable conditions.Extensive experience in the assessment of avalanche danger is required. Remain in moderately steep terrain / heed avalanche run out zones.
5 very high gs4_5 The snowpack is generally weakly bonded and largely unstable. Many large natural avalanches are expected, even in moderately steep terrain. Acute danger.Comprehensive safety measures. Highly unfavourable conditions. Avoid open terrain.
  • 1 The avalanche prone terrain is generally explained in greater detail in Avalanche Bulletin (e.g. altitude zone, aspect, type of terrain)
  • 2 Additional load:
    - high (e.g. group of skiers without spacing, snowmobile/groomer, avalanche blasting)
    - low (e.g. single skier, snowboarder, snowshoe hiker)
  • moderately steep terrain: slopes flatter than about 30 degrees
    steep slopes: slopes with an angle of more than about 30 degrees
    extreme slopes: those which are particularly unfavourable as regards slope angle (usually steeper than about 40°), terrain profile, proximity to ridge, roughness of underlying ground
  • natural: without human assistance
  • Aspect: the compass direction in which a downward slope faces
  • exposed: especially exposed to danger

Danger Scale PDF

 
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