Knowing how to avoid avalanches while hiking could save your life. Avalanches are masses of snow that slide rapidly down a mountain, burying everything in their path. Avalanches kill over 150 people every year. Most avalanche deaths are caused by suffocation, although some victims also die from the trauma of hitting a tree or rock. Staying aware of mountain conditions before and during your hike reduces the chance you will experience an avalanche.
Most avalanches in the United States occur from December to April, although avalanches can happen at any time of the year. Avalanches are more common during or immediately after a snowstorm, especially storms with a foot or more of snow. Rising temperatures can also make snow less stable and trigger an avalanche. Open spaces are usually more susceptible to avalanche than heavily forested areas.
Avoid avalanches by checking the weather conditions before you go hiking. Obey any posted risk codes. In the United States, green indicates that an avalanche risk is unlikely. Yellow indicates a moderate risk of avalanche, while orange corresponds to a considerable risk of avalanche. Red indicates a high risk, while black indicates an extreme risk. In addition, check the stability of the snow by listening for hollow sounds when you walk and looking for cracks or slabs that shear off. You should also dig a four to five foot snow pit with a portable shovel and press your hand against the different layers of snow. Layers of snow that don't feel as hard as the other layers may indicate an unstable situation. Check the stability of the snow several times per day, because conditions can change quickly and may vary in different areas.
If you must cross a slope that looks dangerous, cross one person at a time. Cross slopes at the very top or bottom instead of in the middle. Don't hesitate to turn around if conditions look suspect, and be careful when your group is hungry, tired or otherwise impaired. Do not hike on the cornices of ridge tops.
Even if you take steps to avoid avalanches, you should still be prepared in the event of an emergency. Don't hike by yourself, and always tell someone else where your group is planning to hike. Carry a transmitter and make sure you know how to use it. In addition, ensure your transmitter is set to "transmit," not "receive." Carrying a portable shovel and collapsible probe can also help you rescue an avalanche victim.
If you get caught in an avalanche, try to escape to the side or grab on to a tree. In addition, yell and use swimming motions to try to remain near the surface of the snow. Immediately punch out an air pocket in front of your face if you find yourself buried beneath the snow. Snow rapidly hardens to become as hard as cement, so punch out an air space to prevent suffocation. If you're close to the surface of the snow, try to stick an arm or leg above the surface of the snow. Stay calm; panicking wastes air and energy.