So you’ve been debating whether or not to get one of these new air bag pack things. Is the cost and the weight worth it? Are they dialed in enough to be reliable? Are the packs any air pillow bagsgood for backcountry skiing? Airplane travel? No one you know has one, so why take the plunge?
The statistics are there, and they demonstrate an amazing effectiveness at keeping an avalanche victim from being buried, which translates to a significantly greater chance of surviving. Documented accidents show a 97% survival rate of avalanche victims with an ABS airbag. I won’t go too into the science of how avalanche air bags work but basically they rely on the principle of inverse segregation. If you shake a bag full of sand and pebbles, the pebbles will rise to the surface as they have more volume than the sand grains (this also works with a bag of chips- the big ones work their way to the top).
In avalanches, making yourself bigger can help keep you on the surface, and air bags do Air Bagthat by inflating a bag which increases your size. This is not a new concept and has been demonstrated for years in Europe to be very effective. Given the surprising statistics of survival using avalanche packs, I don’t think they can be ignored in the U.S. any longer. Fortunately, this change is beginning to happen with two U.S. companies making them and several ski patrols purchasing packs (Jackson Hole and Telluride, among others); now, individual users need to jump on board. As opposed to an avalanche beacon which relies on disciplined friends to find you and is therefore a passive safety system, air bags are an active system that you can buy to increase your personal odds of survival. Skiers complain about the cost, but how many don’t flinch at dropping $1000 on new skis, boots, and bindings each season? What about snow tires? No one flinches at that piece of safety equipment. I think it’s time to set priorities and make air bag packs just as important as the beacon, shovel, probe combo (you’d actually be better off with just the air bag if you had to choose). After all, the chances of being dug up alive by your friends are actually not all that good. In a study by the Swiss Federal Institute for Snow and Avalanche Research, 53% of people completely buried by avalanches did not survive, while only 4% of those who weren’t buried died. Your best bet is to stay on the surface, and an air bag provides a significantly better chance of that happening.
Below, I’ve tried to compile most of the meaningful info into one place, based on my experience with some of the packs over the last two years and the experiences of others here at Wildsnow. There is still a lot of confusion surrounding these things, so I’ll try to set some things straight. If I’ve missed something, made a mistake, or if you have something to add, please share it in a comment. This page will hopefully grow and change to become a useful resource. Also, it should go without saying that these packs are no substitute for practicing safe and informed backcountry travel decisions and are no excuse to increase acceptable risk levels.
The Choices Currently, there are now five manufacturers of air bag air bag manufacturersbackpacks and systems: ABS, the original German company; Snowpulse, the relatively new Swiss contender; Backcountry Access, who introduced their pack last year out of Boulder, CO; Mystery Ranch, based out of Montana, who just announced their pack; and Avi Vest, who make a vest that is not compatible with a pack and therefore impractical for backcountry skiing, but are supplying their system to Mystery Ranch. In addition, Rossignol, Dynastar, Arva and Millet make packs that are compatible with the ABS Vario system. All of this is awesome considering that not long ago ABS was the only option!
General Info I’ll go into more depth with each brand later, but some general things to know are:
Use- All of the airbag packs have a handle located on one of the shoulder straps for activating the airbag. When in safe terrain, the handle can be stowed out of reach to avoid an accidental trigger (something to be wary of while bushwacking). When ready to ski, put the handle in the ready position, and if (God forbid) you need to use it, pull on the handle which causes a cartridge full of air to inflate the air bag. Venturi valves are ingeniously used to suck in more air into the bag than is actually in the air cartridge. In an avalanche, your body and air bag are subjected to tremendous forces, and in order for the back pack to not come off you in an avalanche, the pack hip belts use metal buckles, which are much more cumbersome than standard plastic buckles but are needed for strength. In addition, a leg or crotch loop is supplied to keep the pack from being pulled up over your head. This is a pain in the ass, but probably necessary, and the different manufacturers address it in varying elegant and not so elegant ways. After use, the bag needs to be deflated and repacked; it won’t work again until you get your cartridge refilled or if you carry a spare–which might be advisable for multi-day trips.
Testing and Refilling- When you first get your air bag pack, you should perform a test release to familiarize yourself with the process and to make sure it works. Ideally, you should do this while wearing everything you would wear while skiing (or at least goggles, jacket, and your least dexterous pair of mitts), and for extra points do it while skiing on a safe slope. Then, depending on the system you have, you will either have to refill the cylinder or, in the case of ABS which ships you two filled cartridges, return the spent one to recoup your deposit. You should test your bag at least once a season to re-familiarize yourself with the deployment and to make sure it works. I like to do this in the late fall before the season begins.
BCA, Snowpulse, and Mystery Ranch use a cylinder system with a gauge (not a cartridge, which is sealed) that the user can refill with compressed air at certain locations. They recommend using licensed retailers, but any paintball shop can do it or any dive shop or fire station if you have the correct adaptor. Dive shops require a paintball to SCUBA adaptor, while fire stations require a paintball to SCBA adaptor. Your home compressor or gas station won’t cut it, you need 2700-3000psi (varies by manufacturer). I have found some fire stations to be very helpful and accommodating, they probably won’t charge you anything, so be sure to make a donation to keep them happy, and always call in advance. Also, when the cylinder is filled, it will get very hot; you must let it cool down and then top if off again (gas expands when it is hot), a water bath will work for this. After refill, the O-ring must be replaced and silicone grease reapplied, then everything sealed up again to keep water out. It’s a bit of a ‘DIY’ project, but very doable if you follow the instructions. I love having the freedom to refill when I need and not having to deal with any shipping. One other thing, regardless of how you get the cylinder filled, there is a two step process to attaching it to the pack. The cable that goes to the activation handle must be attached to the release pin (don’t accidentally pull it out!), and the valve must be attached to the hosing that goes to the air bags. Not difficult, but not as idiot proof as ABS.
Air Travel- Flying with your air bag backpack is not a terribly difficult thing in most of the world, provided you notify the airline in advance, follow the instructions provided by the manufacturer, carry the material safety data sheet (download it off your manufacturer’s website), and bring it as a carry-on, NOT checked luggage. However, the U.S. is a different story due to our paranoid TSA. The manufacturers have worked with the Department of Transportation to get their U.S. cartridges DOT certified, but there are also Euro cartridges out there that are not. ABS’s system is by far the easiest as their cartridges are sealed without a valve. Just make sure the filled cartridge and the explosive activation handle are not attached, but loose inside the pack. The cylinder systems (Snowpulse, BCA, MR), however, must be emptied and, according to current TSA restrictions, must have the cylinder head assembly removed for visual inspection of the inside. This can be done by unscrewing the head from the body–you may need wrenches to overcome Loctite, which may or may not be there. Screw it back on hand tight when you arrive at your destination, and skip the Loctite. Despite what is officially allowed, your experience may differ based on which TSA agent or airline official you get. Your mileage may vary, but you can read about some travel experiences and advice as posted on TGR. If you have any travel experiences, please chime in.
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