Avalanche deaths have increased in the United States since 1950. Most deaths involve men, and the average age of all victims is 27 years.
Most victims were pursuing some form of recreation at the time of their accident, with climbers, ski tourers and downhill skiers heading the list of casualties. Since 1950, 14 states have recorded avalanche deaths with Colorado leading and followed in order of deaths: Washington, Alaska, California, Utah, Idaho, Montana, Wyoming, Nevada, Oregon, New Hampshire, Maine, New Mexico and New York.Several factors affect a buried victim's chances for survival: time buried, depth buried, clues on the surface, safety equipment, injury, ability to swim with the avalanche, body position, snow density, presence of airspace and size of airspace. Avalanches kill in two ways.
The first way is from serious injury acquired while tumbling down an avalanche path. Trees, rocks, cliffs and wrenching action of snow are hazards. About one-third of all deaths are related to trauma, especially to the head and neck.
Second, snow burial causes suffocation in two-thirds of avalanche deaths. Inhaled snow clogs the mouth and nose and suffocation happens quickly if the victim is buried with the airway already blocked.
Snow sets up solid after an avalanche. It is almost impossible to dig yourself out, even if buried less than a foot deep. The pressure of the snow in a burial of several feet sometimes is so great that the victim is unable to expand his or her chest to breathe.
A completely buried victim has a poor chance of survival. In the first 15 minutes, more persons are found alive than dead. Between 16 to 30 minutes, as many are found dead as alive. After 30 minutes, more are found dead than alive. Speed is essential in the search. In favorable circumstances, buried victims can live for several hours beneath the snow; therefore, rescuers should never abandon a search prematurely.
A buried victim's chances for survival also depends on the type of rescue. Buried victims rescued by party members or groups at the accident scene have a much better chance of survival than those found by organized rescue groups. A shallow burial means less search time, shorter digging time and perhaps attached objects or body parts may be visible.
Organized probe lines have found more victims than any other method, but because of the time involved, most of the victims were dead. Rescue transceivers are an efficient way of locating victims.
Trained search dogs can locate buried victims quickly, but they are often brought to the scene only after long periods of burial. A trained dog can search more effectively than 30 searchers. Dogs have found bodies buried 10 yards deep but have also passed over some buried only 2 yards deep. Trained search dogs are becoming common fixtures at several ski areas in the U.S.
If you are a victim
- If the snow begins to move under you, first try to escape to the side of the avalanche or try to grab onto a tree. Try to stay on your feet. Don't try to outrun an avalanche, since it usually can overtake its victims.
- Shout, then shut your mouth. Breath through your nose to avoid inhaling a mouthful of snow.
- If knocked off your feet, put all your effort into swimming with the avalanche. Get rid of heavy gear, toss ski poles. The purpose of this swimming maneuver is to maintain a position near the surface. If you are being carried headfirst downhill, use a breast stroke with the arms; if being carried down feet first, try to roll onto your back and attempt to "tread water" with your arms and legs.
- When a victim feels the avalanche slow down, this is the best time to reach the surface. Use swimming motions, try to burst through to the surface. Even if the head doesn't emerge, being near the surface greatly improves survival chances.
If you are a survivor
- Mark the spot where the victim was last seen with a piece of equipment, clothing or tree branch.
- Search the area below the last-seen point for any clues of the victim. Make shallow probes into likely burial spots with a ski, ski pole or tree limb.
- If beacons were being used, all survivors must immediately switch their units to the receive mode and listen for a beeping sound from the buried beacon.
- Under guidance of a trained rescuer and with probes, probing avalanche debris is a simple but slow method for searching for buried victims.
- If a second avalanche is possible, place one person in a safe location to shout a warning so rescuers can flee to safety.
- Send a person to notify the ski patrol immediately if near a ski area and there are several rescuers. If you are the only rescuer, do a fast surface search for clues before leaving to notify the ski patrol. In remote backcountry all survivors should remain and search until they cannot or should not continue.
Anyone traveling into potential avalanche country should call the 24-hour regional avalanche information telephone number found in the directory under the U.S. Forest Service.
Alton Thygerson is a professor of health sciences at Brigham Young University.