Will Sim: Blue skies and deep powder. Cold, clear and still. The sub-zero air stung the little-exposed skin of my cheeks, and the taut atmosphere of a winter's day excited me. Directly beneath us lay a virgin carpet of feather-like snow, nearly 2000 meters of it, not yet touched as it was early and this was the quiet side of the mountain. But then a faint sound entered my thoughts through my ear - my brain was kicked in to a higher shutter speed, but not fast enough...
"... people often survive the impact and tumble of an avalanche, but then suffocate, buried beneath the surface. But isn't snow 50% air? Can't you breathe through it? No you can't - but this is what an Avalung does..."
Within little over a second the sound had increased to a deafening roar then receded to a background rumble, and it had taken one of our group with it. Debris was shooting down a gully in the buttress above me like a flume at Wet and Wild. After what seemed like a while, but was no more than five seconds, the debris ceased and revealed a tongue of mangled up blocky snow stretching some way beneath. To our relief, as the rest of us made our way down, a blue figure squirmed its way out of the debris. We had been lucky - the avalanche had spat him out short of the gaping crevasse not far below.
In my experience of such matters, when things go wrong in the mountains, they can go very wrong very fast, and avalanches are the perfect example. For climbers wind slab, rock fall and sloughing couloirs are real dangers we learn to avoid and deal with. And for skiers, specifically people who venture off the pistes, avalanches are an even-more present danger.
What's an 'Avalung'?
I explained to a friend the other day that people often survive the impact and tumble of an avalanche, but then suffocate, buried beneath the surface. He said, “But isn't snow 50% air? Can't you breathe through it?” Well, no you can't - but this is exactly what an Avalung does.
In recent years several products have been developed to improve your chance of survival in an avalanche: if you ski regularly you will have no doubt seen people wearing ABS (Avalanche Airbag System) or Avalungs - both look like normal day bags, and serve as this too. Inside, an ABS has two deflated balloons. If avalanched you pull a toggle to make the balloons inflate; increasing your volume by about 150 litres and making it harder for you to be dragged under by the circular motion of the churning particles within the avalanche. Unfortunately an ABS doesn't turn into a massive balloon trapping you with a beautiful Russian girl, as Pierce Brosnan found in the 'World is Not Enough'.
The Avalung, on the other hand, assumes that you've not managed to float to the top of the debris, and the slide has come to a stop with you submerged. It then filters out the air contained in the snow through a valve at shoulder level, which you breathe in through a flexible mouth-piece attached to the shoulder strap. When you exhale into the same mouth piece the Carbon Dioxide is released through another valve, this time at the very bottom of the bag, so as not to contaminate the air around the intake valve.
The amount of available data concerning survival rates in avalanches and success rates of products such as ABS and Avalung packs is vast and contradictory. That's because no avalanche is the same: snow density, size, collection area and timing all have a huge impact on the victim's position and available oxygen under the snow. However, 15 minutes is generally accepted as the time you have before running out of oxygen in an avalanche - assuming your airways are free. If not rescued during this 15-minute window, chances of survival reduce dramatically, as you'll soon become unconscious. (Read a story of an avalanche survival using the Avalung at www.telemarktips.com)
Obviously this is in avalanche debris, which has a much lower oxygen content than most snow due to the friction and liquidation that occurs during an avalanche - I've also tested the avalung in a hot tub, but in this case I think the oxygen content was pretty much zero...
Tests carried out during the development of the Avalung showed that its technology can delay the onset of hypoxemia (insufficient oxygen in the blood) by up to 60 minutes, with an average result of 58 minutes, thereby more than tripling the amount of time you can survive before rescue.
When reading statistics like this, the Avalung seems an almost fail-safe talisman against avalanches. However, there are a lot of other eventualities to be taken into account once an avalanche takes hold of you. Firstly, you might not be conscious or even alive when you stop, due to battering within the slide's 'washing machine cycle'. Secondly, in more powerful avalanches, the Avalung bag could be ripped off your shoulders - highlighting the importance of fastening the chest and waist straps.
And thirdly, your airways might be blocked by snow packed down your throat and nostrils. To avoid this, it's crucial to position the Avalung mouthpiece extending past the shoulder strap, so that as soon as there is danger of being caught in an avalanche, you can put the pipe in your mouth and start breathing through that, rather than breathing in snow.
It's worth noting, before running towards heavily-loaded, 40-degree slopes armed with Avalungs and ABSs, that these systems are designed to up your survival rate in a worst-case scenario - not to make you invincible. If you're going to head out in winter conditions climbing or backcountry skiing, you'll still need to have a healthy respect for danger, and know how to avoid situations where you are likely to be avalanched. You'll also need to know what to do with shovel, probe and transceiver if it happens to someone else in your group.
Black Diamond Avalung-equipped packs
Black Diamond make a large variety of Avalung packs. However, it's the pack that varies not the Avalung. There are many different shape and size packs available, ranging from 11 to 42 litres, and all have cool names like Bandit, Outlaw and Anarchist.
A deluxe all-purpose Avalung-equipped pack.
I've been using the Outlaw extensively for the last two winters and, Avalung aside, it's an awesome size pack, which fits well and is well-designed for its purposes: all types of skiing including lift-based, touring or serious steeps. Obviously the latter is a special case, as with many steep descents you may wish to be equipped more as a climber than a skier.
The Outlaw is a 30 (or 32) litre bag split into two compartments. The main (larger) compartment is the actual storage area, and can be accessed either from the top zip, or a large zip right down the back support which enables access to everything, no matter what order it was packed in. The smaller outer pocket has pouches made to keep all your equipment, such as shovel and probe, stowed away neatly, and perhaps more importantly to prevent them from causing injury to your back in a fall. The bag also features several small zipped pockets for wallet, keys etc.
Specifications aside, the main thing is that this bag is super-comfy. If Black Diamond made this bag without the Avalung and for climbing, I'd get it. It hugs your back like nothing else. Which, for an activity like skiing that is so balance-orientated, is crucial. Also, for a 30 litre bag with a number of partitions, several valves and a load of piping the Outlaw weighs in at a surprisingly light 1.6kg. Anybody who's been skiing can appreciate the values of a light bag.
A streamlined, lightweight Avalung-equipped pack.
Jon Griffith: Black Diamond's 30 (or 32) litre Avalung pack, called the 'Alias', is marketed as a lightweight pack with an integrated-Avalung system. As Will has already explained, the Avalung system allows you to massively increase your chances of survival once buried.
The Alias is a strange pack in that it's aimed primarily, I think, at a niche market of skiers - overnight ski tourers. The majority of ski tourers who overnight somewhere will stay in a hut meaning that 32 litres could be considered excessive. On the other hand, those who are happy staying in a winter bivouac are probably the same type of people who will happily eschew the extra weight of the Avalung system to go as light and fast as possible. However BD are no new-comers to the rucksack market and to overcome these barriers they have designed a lightweight pack that only weighs 1.5kg with the Avalung included. When you consider that the Outlaw weighs in a 1.7kg you can appreciate the effort put into this pack.
The Alias is large enough to hold any overnight equipment, including sleeping bag and stove, and an external pocket flap means that you can keep all your avalanche kit separate from your main pack, so you won't be chucking out all your bivy kit in desperation to find your shovel and probe if the moment does arrive. As with all BD packs the fit is great. I think this is where BD really win on the pack front - for me anyway - while they might be slightly heavier than other competitor packs the back support is awesome.
On the face of it, the Outlaw and the Alias might seem like very similar packs. Both are 30 or 32 litre packs and they both have the Avalung system. However the similarities stop there: the Outlaw is a very functional day pack, which is unbelievably comfy to ski in and wear. The compartmentalized sections means that storage and separation is very easy and the back door access panel is brilliant as stuff is easy to access. It is not a top-loading pack so while 32 litres might seem large, if you only put 20 litres of stuff in there it will easily compress down so it won't seem bulky.
However, as it is a front-loading pack, it doesn't hold kit as efficiently as a top-loading one, so you can't pack as much into the space (basically a top-loading pack is narrow and long, while a front-loading one is fat and short). The Alias, on the other hand, is a top-loading pack aimed more at the ski-touring market. The attachments for skis are better designed and, since it is top-loading and is a taller pack, it's easier to carry skis on it. The bare bones design means that you shed 200g off the weight of the Outlaw and end up with a more streamlined pack.
It is impossible to say which pack is best, as they are designed for different markets. At the end of the day they both do the same job - they keep your gear on your back and might save your life one day, the difference really is whether you want a rugged day pack for lift days or a pack that you will want for touring. My personal preference has been for the Outlaw but then I don't do many over night tours - when I do overnight then I always bring the Alias.
"At the moment I climb non stop for three quarters of the year, then spend a few months milking cows, shovelling shit and spreading muck on a dairy farm in my village. I've been climbing since I was 12. My main interest is climbing big stuff fast. But I still enjoy a sunny days cragging just as much. Will maybe go to Uni one day, but don't see any rush."
Jon Griffith's first climbing days were in the Avon Gorge at Bristol. After university he moved to Chamonix, where he works as a professional mountain photographer: Alpine Exposures.
"It's hard to pick one specific type of climbing that I prefer over the others but I think my heart still lies with big mixed alpine routes that potentially involve a couple of nights bivying. I am still getting used to the whole Chamonix 'get back in time for the last lift' style - I still include bivying as a part of any decent mountaineering experience. I am also still getting used to crack climbing - it hurts.... a lot.".