If you spend any portion of the winter in the backcountry, you’ve probably heard of avalanche airbags (ABS or Air Bag System). These packs have been popular in Europe for a number of years, and have recently become vogue in the States. Survival stories from using these packs are popping up across the internet, but marketing behind them can be confusing. This article takes a look at how these bags work and why they’re effective, as well as some limitations of their use.
How They Work
The science behind the design is pretty interesting. Although the inflated pack looks like an oversized life jacket, they aren’t intended to mimic a floatation device. Instead, they’re designed to make a human bigger so the person will rise to the top of the slide. The theory is often compared to shaking a bag of chips or a can of mixed nuts: the largest pieces end up on top. Asphyxiation and trauma are the most common causes of death in an avalanche; a person who ends up near the top of an avalanche is less likely to hit things (trees, rocks, etc.) and less likely to be buried. Although the bags are gaining popularity, they are not cheap—an ABS pack can cost between $500 and $1000. For backcountry skiers and riders (and ice climbers and snowmachine enthusiasts) who like to fly to their favorite backcountry location, an airbag is a hassle because federal law prohibits flying with the cartridges that inflate the bags.
One reason these packs are becoming more commonplace in the Americas is the mortality statistics associated with their use. Manufacturers of the ABS packs advertise a 97% survival rate for people who successfully deploy their bag. This number is high enough to make any backcountry skier/rider reconsider the steep price tag. But what does this statistic really mean? It turns out that the survival rate for people caught in avalanches (all kinds, even small ones) is already pretty high. The most recent studies suggest that about 81% of all people caught in an avalanche survive. Another consideration is that 97% is for successfully deployed bags. Statistics from 2011–2012 show that the bags only inflated properly about 89% of the time. In short, wearing an airbag is not the same as having an airbag that successfully deploys. As with all statistics, understanding what the numbers mean goes a long way toward understanding how the product can be helpful. These airbags are not a magic bullet for avalanche safety, but they do increase the odds of survival.
Avalanche beacons, avalanche forecasts, and better shoveling techniques have all decreased the number of avalanche deaths. Airbags are likely to bump that number even higher, as long as the people who are wearing them still use good judgment. However, if wearing an airbag causes people to make riskier decisions, like picking routes in dangerous terrain, where the risk of hitting objects increases, or going out despite high avalanche risks, then the statistics may begin to change. Like all safety gear, nothing replaces strong risk management and smart choices. If you spend a lot of time chasing powder in the backcountry, consider taking an avalanche course, where you’ll more about snow science and how to this gear effectively.