the blizzard bag as indicated is tested to 8 togs … its a bona fida "sleeping bag" and bivy combined … i believe it is now used by the army for initial hypothermia treatment
in winter or alpine day trips i carry one … in the summer id just bring a 4 oz heatsheets bivy on rock climbs because functionally in the summer id likely survive with one … in the winter or even the shoulder seasons, its questionable …
13 oz is not that much when you consider you are carrying a bivy and sleeping bag combined … and that it costs ~$30 (im sure some people will go on here about how they can get a quilt and bivy for the same weight … but not for that price!!!)
8 togs = 0.8 m2 k/w … as you can see below 8 togs is the equivalent of a 9C COMFORT en-rating for women and 4C for men and a -11c en-extreme rating
heres a review
http://greenbeetlegear.me/2010/08/26/blizzard-bag-review/
and heres a review from someone who used it across the uk
n 2009 I made the first ever attempt to run the length of the UK off-road, I succeeded. 1,254miles across trails mountains, moorland and highlands. An average of 30miles a day for six weeks, the run took 45 days and 17 hours, including 3 rest days.
Two weeks before the start of the event, plans for a support crew fell through, I had to run solo and unsupported. I almost dropped out of the challenge, two weeks before the off, I was already having butterflies and losing sleep over the enormity of the route, which includes enough ascent to climb Everest several times over. Having no support crew, would be tough psychologically, but the glaring problem it created was weight – I had to carry all my kit, running 'mountain-marathon' style. I didn't know if it cold be done, I hadn't trained to take the extra strain of a pack for that length of time. i'd already made a commitment to go through with the run, so I only had one choice – slash weight as much as possible, 'trimming the fat' of any piece of kit and the kit list it self.
One of the biggest weight savings I made was in my sleeping system. In adventure races you carry either a very light tent or if crazy just a sleeping bag and a waterproof cover 'bivi bag' I had both options available to me – but looking at the numbers both options were too heavy. I'd already gone to extremes- cutting the handle of my toothbrush (yes a few grams saved here and there really does add up especially when your running over two million steps!)
To have confidence in finishing the run i knew I had to go as light as possible – while remaining safe. I began looking at ways to ditch the sleeping bag, perhaps using foil blankets inside a bivi bag would be enough to keep me alive at night yet light enough to carry through the day.
i knew I was being desperate now – there was no way that system would work, as soon as I moved the foil sheets would move away from the body losing all insulation properties instantly.
I spoke to a mountain leader friend of mine who always carried a vacuum packed 'blizzard bag' made of foil – asking if they were just glorified foil blankets- aparantly not, he informed me they were actual sleeping bags made out of several layers of foil-and importantly they were designed to be re-usable, i.e. they didn't tear after one use.
Looking through the blizzard survival website and after phoning the info line i decided to go with just a foil bag – one piece of kit instead of two that did the job of both 'bivi' bag – it's fully waterproof, and sleeping bag – it's insulated – having three layers of foil I could see how it would work like a down jacket – trapping pockets of air.
I figured the bag would last one week maybe two at most – planning to ask family or friends to post replacements ahead of me along the route. I was happy – with half a sleeping mat and a tarpaulin to cover my head, I knew I had the lightest practical sleeping system to tackle a mountain marathon challenge. The whole system came in at under 700g.
It might seem excessive to just save 300g but the run was approx 2.4million steps, that 300g had to be lifted on every step 2.4Million x 0.3kg = 720,000kg's! 720 tonnes of extra lifting! It's that extra strain that could see an athlete fail short of the mark. It cold well have been the difference between sore feet and stress fractures. Imagine running a marathon Everyday over mountainous terrain – then at the end of each week having to lift over a hundred cars before repeating the same the following week, over these distances saving weight – whilst keeping equipment sable and safe is paramount.
To my surprise the bag lasted over a thousand miles before it started to show signs of abuse, the bag is designed to be used in emergencies – and be reusable for the next emergency you encounter. used nearly every night for 6 weeks – packed a way wet, sat on like a cushion during food stops, this thing was abused – and it lasted.
In my opinion, any athlete looking for the lightest possible sleeping system on the market today, that is actually still practical to use should look no further than a Blizzard Survival bag. I won't lie, its far from comfortable, it doesn't breathe well (but in my opinion no gore tex bivi can deal with the amount of sweat coming of an athletes body after running a marathon over mountains) you will get wet with condensation – but you will be warm no mater the weather outside. The weight saving is too much of an advantage for any athlete to look-over, when wanting to travel fast and light nothing compares.
Kevin Carr.

