Understanding Avalanche Safety and Airbags

avalanche

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.

AirbagHow 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.

Sta­tis­tics
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.

Oth­er Fac­tors
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.