avalanche(redirected from avalanches)
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Wilderness medicine A natural disaster in which massive unsorted mixtures of snow/ice/rock/mud cascade down a steep incline. Powder snow avalanches can exceed speeds of 300 km/h, and masses of 10,000,000 tonnes
Statistics Europe, 150 deaths/year; USA/Canada, 15/year; most are recreational—e.g., snowmobilers, mountaineers, back-country skiers
Avalanche risks Decreased snow stability; slope angles > 35º
Emergency action Do not wait; even in well-equipped ski areas, helicopters take 45 minute to arrive
Survival 15 minutes—85%; 30 minutes—40%; 1 hour—20%; 2 hours—0%
Cause of death Crush injury, hypothermia, suffocation