Skip to main content Skip to main navigation Skip to side navigation Accessibility Statement. Home Public safety and emergency services Emergency management Public preparedness and recovery Know your hazards.
Section Navigation. Know your hazards. Earthquakes and tsunamis. Severe weather. Power outages. Hazardous material spills. Pandemics and disease outbreaks.
Hazard map. Build your kit. Make your plan. Guides and resources. Evacuee guidance. How did this happen? I know the mountains are inherently dangerous but how could this happen to me? What can I do to feel better about my backcountry trips this winter? The conventional avalanche wisdom says, "There are no rules of thumb. There is a particular set of physical and human factors that underlie each accident. There is a lot of knowledge that you can acquire about the factors that result in avalanche accidents.
It starts with some basic awareness. Who gets caught and where does it happen? Avalanche statistics tell us about the nature of the beast.
Most accidents involve slab avalanches. The victim, or a member of the victim's party, usually triggers the slab that kills them. Skiers and climbers make up the bulk of the numbers. However, snowmobilers and snowboarders are surpassing the old guard at an alarming rate. Slab Avalanche Crown [ click to zoom ] photo: Northwest Avalanche Institute Last year, the snowmobile category alone accounted for almost half of the fatal accidents in North America.
What you do and where you do it become important as you learn about avalanche hazard. The profile of the accident can vary with time of season and place. In Montana, a snowmobiler, with little or no avalanche awareness, may release a dry slab avalanche, while "high marking" in midwinter. By spring, we may see an experienced climber on a northwest volcano, knocked off of a steep slope by a small loose snow avalanche.
Not only do you need to be aware of local snow and weather factors, but also of what particular hazards you face, based on your statistical profile. Where do I begin? Start by arming yourself with a solid understanding of the fundamentals. Avalanche conditions form as a result of the interaction of terrain, weather, and snowpack.
All of the information we use to predict snow stability is in this triangle. Learn to recognize the subtleties of avalanche terrain.
Most mountain travelers can spot the obvious paths. But learning to anticipate where on a particular slope that a fracture will occur, and how far it may propagate, takes some study. Learn to pay attention to the weather. Storms are the source of most the world's avalanches. The combination of new snowfall and wind creates the unstable layering that result in slab avalanches. Simply put, during a storm, the rate at which stress is added to the snowpack exceeds the rate at which these new layers can gain strength.
Skiers and climbers make up the bulk of the numbers A prolonged period of cold and clear weather can substantially weaken the snowpack. This can set up a hair trigger situation. Learn to "feel" the snow. Once you have a good grasp of the physical processes that determine the layering of the snowpack you can begin to "feel" the snow. Qualities like the stiffness or styro-foam texture of the snowcover are significant. Hollow sounds, cracking, or collapsing are also important field observations.
As each clue is observed, they need to be related to the processes at work. This may be what your instincts are telling you to do, but avalanches are fast and can quickly overtake any skier or snowboarder. Avalanches can come downhill at speeds of up to 80 miles per hour. If the avalanche is starting right beneath your feet, which can happen while snowboarding or skiing, then you need to move quickly and try to jump upslope if you can to get above the fracture line.
This is a difficult technique to master, and it requires quick reaction times to be successful. If you do find yourself in the path of an avalanche and you are lucky enough to grab onto a sturdy rock or tree branch, it can keep you steady and rooted to one spot.
If it is a major avalanche, then your anchor will likely go along with you. However, being able to hold on for even a short period of time before being uprooted can keep you from being buried as deeply under the snow, increasing your chances of survival.
Once you are already caught in an avalanche, doing these things can help increase your chances of survival. Your best chances of survival are to stay on top of the snow, as doing so will diminish your chances of getting buried by snow and debris once the avalanche stops. Use swimming motions to help prevent yourself from the debris and snow dragging you down and then keeping you there.
Use all your muscles and swim with the current. Holding onto bulky and unnecessary gear can drastically decrease your chances of survival during an avalanche. Non-essential equipment can make it more difficult to swim on top of the avalanche, and its weight can encumber you and make it more difficult to stay afloat. Release your skis and snowboard if you can. Let go of your poles, but still continue to fight your way to the side of the avalanche. If you release equipment and small pieces of clothing, such as your scarf and gloves, it can make it easier for people to find you if any of it settles on the surface.
However, you should keep your backpack on, as it will protect your spine and you will need access to safety gear inside during the rescue.
Additionally, it will make you larger and brighter avalanche airbags generally come in bright colors like red and orange so that you can be more easily found by rescuers. Though perhaps not intuitive, keeping one arm up during the avalanche can be an important aspect of survival.
Keep one arm up at all times while you are riding out the avalanche. Many fatalities related to avalanches are due to asphyxiation. Once an avalanche settles, the snow will settle as hard as concrete, and your supply of air—as well as your ability to breathe—is going to be limited. Holding your breath as the snow settles and expanding your chest by filling your lungs with air can provide you some room to breathe.
Once the snow hardens, that space will be lost, so you want to have the ability to inflate your lungs. Clearing the space in front of your face can help create air pockets that will give you space to breathe. Before the snow fully settles, use your hands to dig a pocket of air around your face.
Digging these air pockets can give you up to half an hour of breathing time. By spitting, gravity will be able to tell you which way is up depending on what direction your saliva flows. You can then start digging up, which will increase the chances that Search and Rescue locates and saves you.
Spitting also helps create more room in front of your face so that it is easier for you to breathe. Staying calm is important because panicking causes you to breathe quicker. Think about how you will be packed into a tight gap in the snow and how fresh air will be limited, even while you are doing all you can to create room to breathe.
Try to breathe as steadily as you can in order to give the rescue team as much time as possible to save you. You will need a focused and clear mind to remember the knowledge you have in order to evaluate your next steps for the best chances of survival. As soon as someone is caught in an avalanche, do your best to track their path.
If they disappear below the snow, make a note where you last saw them and continue to watch downhill to see if they resurface. If you have been following the proper avalanche safety techniques, then only one person should have been in the danger zone at that time. Make sure the avalanche has stopped and the area is safe before anyone else enters the slope and begins organizing a rescue.
Take a look at the surface of the snow in order to find any clues or signs of the victim. If you know the person was carrying an avalanche cord, you can also search for that.
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