Here are some myths about avalanches from the Utah Avalanche Center:
Myth: Loud noises trigger avalanches
Reality: Although it's a convenient plot device in the movies — and most recently on Jeep commercials — noise does not trigger avalanches. It's just one of those myths that refuses to die. Noise simply does not have enough force unless it's an extremely loud noise such as an explosive going off at close range. In 90 percent of avalanche fatalities, the avalanche is triggered by the weight of the victim, or someone in the victim's party.
Myth: An avalanche is a bunch of loose snow sliding down the mountain.
Reality: Avalanche professionals call these "sluffs." Loose snow avalanches account for only a very small percentage of deaths and property damage. What we normally call avalanches are "slabs" or cohesive plates of snow that shatter like a pane of glass and slide as a unit off the mountainside. Picture a magazine sliding off the table, with the victim standing on the middle of the magazine. This is why avalanches are so deadly.
Myth: Avalanches strike without warning.
Reality: We often hear the word "strike" used in the popular media. Stock market crashes, meteor impacts and lost love may strike without warning, but avalanches almost always have obvious signs. Second, avalanches don't "strike." They happen at particular times and in particular places for particular reasons. Natural avalanches occur because new or windblown snow overloads weak-layers or because of rapid warming, but there's almost always obvious signs of instability by the time avalanches come down on their own.
Myth: If you see an avalanche coming, get out of the way.
Reality: Well, at least you can try. An average-sized dry avalanche travels around 80 mph and it's nearly impossible for someone to outrun an avalanche or even have time to get out of the way. A fast snowmobile has some chance but everyone else has a slim chance at best.
Myth: All the avalanche experts are dead.
Reality: We can report just the opposite. Skilled avalanche professionals enjoy a very low avalanche fatality rate compared with other groups. Less than 1 percent of all avalanche fatalities involve avalanche professionals.