Avalanche Safety Series Part 2: Hazard, Risk & The Big Lie
“We are not operating in a benign environment where incidents occur as the result of an individual deviance from a prescribed protocol, we must be conscious that we operate in a high-risk environment where hazard is constantly present and conduct ourselves accordingly.”
- Mark Smith, The Big Lie
The rewards of riding in the backcountry with friends can be sublime. The best days of our lives, that enrich and nurture us. But there’s a dark side to our life-affirming passion. Avalanches are dangerous. The consequences are serious, often life-changing or final.
If we’re going to interact with avalanche terrain by skiing and riding the backcountry we need a toolkit of skills that includes a systematic process of making an assessment of the avalanche hazard before going into the mountains each day, and once in the mountains the ability to reevaluate the hazard:
What is the relevant avalanche hazard today?
Where will this hazard be present on the mountain?
How serious a hazard is it?
How will we mitigate the risk it imposes?
In our previous blog on decision making, we found that 90% of human-involved avalanches are set off by the victims themselves. It’s such a powerful statistic because it shows we decide the risk we are willing to expose ourselves to of being avalanched. We can literally choose if we’re going to get avalanched!
It breaks down like this:
What is the probability of us being avalanched here?
What are the consequences of us being avalanched here?
Probability x Consequence (avi size + vulnerability & exposure) = Risk
Predicting the probability of where and when avalanches will occur is an uncertain business. Throughout the winter, skilled and experienced forecasters have a daily inner struggle to prescribe the correct hazard rating for their forecast area. If the pro’s struggle, then for us to address that uncertainty it’s important that we add a margin of safety. Fortunately, we can add margins in all sorts of ways. Carrying rescue equipment and being well practiced with it adds a margin, as does skiing one at a time and minimizing our exposure to avalanche prone slopes. The margin of starting early, the margin of not constantly operating at the edge of our skill ability, the margin of being with an experienced strong team that communicates well…there are dozens of margins we can add every day. It’s all these small margins that when put together allow us to operate safely in Smith’s high-risk environment such as the winter mountains.
Predicting consequence is much easier. If I get avalanched on this slope I’m about to ski, what’s the likely outcome for me going to be? Is a question I’m constantly asking myself when skiing in the mountains. For example:
If we drop into a narrow 45-degree rock lined couloir that funnels out into trees or over a cliff, then we need to be certain that the probability of the slope avalanching is extremely low, because the consequences of being caught in an avalanche in such terrain would be extreme.
Risk is a personal matter. Our risk tolerance is as individual as ourselves. Even within ourselves our risk will vary and change over time. Experience has a direct influence on our risk taking, as friends are lost in the mountains or we suffer the personal consequences of a serious injury, then we tend to dial things back. In our personal risk equation, we judge that the reward doesn’t always warrant the risk. Experience is the result of going nose to nose with consequence. We move to operating within the ‘green’ zone of the various avalanche risk assessment tools such as the Canadian Avulator or the Swiss Munter reduction method where both the probability and consequence are both low and come together to give a ‘green’ light.
But as Manuel Genswein the Swiss Avalanche expert critically points out, we forget the crucial element of repeated exposure. Yes, by operating in a safe consistent manner and keeping it in the ‘green’ we can pull the risk back to a 1:100,000 risk of death every time we go ski touring (source: based on British Health & Safety Executive) — not dissimilar to driving a car, but we must factor in repeated exposure.
“Because you obviously accumulate exposure over your life.” The more frequently you go out and the greater the level of hazard you expose yourself to each time, the greater your likelihood of dying — each time (the risk remains 1 in 100,000 even on your 100,000th ski tour).
So here is the reality of the ‘Big Lie’ of backcountry skiing. Repeated exposure for a very frequent backcountry skier — say a ski patroller or guide, one who on every occasion follows all the protocols all the time still has a 1 in 50 chance of death by avalanche over their lifetime. If his risk acceptance finds him constantly riding in the red zone it drop to 1 in 12.
What is your risk acceptance? It doesn’t matter if it is much greater or much less than mine. But it does matter that you know what it is for yourself. Constantly ask the key questions: What’s the probability of this slope avalanching? What are the consequences if this slope avalanches? Each of us should be comfortable where we stand in our personal risk verses reward equation.
Avalanche Geeks are the avalanche safety partner of FATMAP, an avalanche education company that provides courses and training for the public and mountain professionals in the European Alps & Scotland.
