http://www.blizzardprotectionsystems.com/

This is a fascinating technology, and it seems to me it could have some use for the backpacker or mountaineer. One of these might make an excellent liner for a summer bag to turn it into a winter bag with a built in vapor barrier. This thing got a positive write up at Psychovertical.com. What do people think?

It seems no one noticed my first post so I thought I'd try again.

Looks a little crinkly (and possibly fragile) for regular use. That said, I keep a Space Blanket type bivy in my pack 365 days a year. This product looks superior!

Sounds a lot better than the traditional "space" blanket.

However, it claims to have about 3/4 of the thermal resistance of a in-home winter bed quilt, or about 2.25x the warmth of a in-home SUMMER bed quilt.

Don't know about anyone else, but, for me personally, neither of these measures of comparison mean that, alone, it is going to keep me warm below 50F-55F (which my BR was when i heated with a coal stove located in the Den; BR was furthest fr/the stove) if i'm wearing flannel winter bed clothes, down sleep socks, and a beanie. Think about sleeping in your bed at 50F (probably a tad colder than most keep their bedrooms). Now, remember the matress is providing some underbody insulation. Also, remember "sleeping", so no activity to add warmth.

I just can't picture myself using my winter bed quilt on top of my hiking clothes and Cocoon pullover and keeping my self warm at some point below 40F, and this has only 3/4 the warmth of my winter bed quilt (2/3 the warmth if i use the independent Laboratory's test results and NOT the Mfr's test results).

Forget the reflective nature (the air the product traps is more significant in providing warmth), The reflectivity, IMHO, essentially does nothing as radiative heat loss at body temp is very minimal compared to convection, conduction, and evaporation (if not wearing VBC).

Here's what their website says: "As a rough guide, if you are wearing the type of clothes appropriate for the season and you make some effort to find a sheltered spot and put some insulation underneath you, then in spring, summer and autumn you should be warm and comfortable. In winter you may not be so comfortable, but you should be able to survive for several days in all but the most extreme conditions."

Did anyone notice the words "so comfortable"? Now, there's an understatement, IMHO! THIS IS A JOB FOR....

EN13537!!!


Please correct me if you think i'm wrong, but sounds to me like MOST of the warmth is coming from the clothes being worn, the underbody insulation, not to mention lack of convective heat loss due to the wind sheltered bivouac site.

I'm just guessing, at some point below 40F nighttime temps (how much below? don't know. RN, your turn, i'm sure that you have some examples/numbers), survival isn't possible due to hypothermia.

Their concept of summer & winter though, might be skewed by their UK winters - a bit different, i'm guessing (UK participants, please help me out here), than northern US & CAN winters, in several respects.

Having said all this, i'll have to check the cost, as i may purchase one, but i don't expect it to keep me alive in the winter w/only my clothes+Cocoon and w/o a sleeping bag.

Edited by pj on 01/31/2007 04:23:57 MST.

Can anyone, maybe Richard, translate "8 togs" into inches of down loft so I can get my mind around this? At a miniumum I carry an Adventure Medical 2 person emergency bivy and goretex bivy sack, and it still weighs less. This is a heavy product.. but maybe thats a lot more insulation?

Edited by Brett1234 on 01/31/2007 22:21:31 MST.

8 togs is approximately equivalent to 1" of low quality down or 3/4" of high quality down (800 fill).

So, IIRC, at 45F, 3" of total loft (1.5" of loft for quilt users) is generally the figure many sleeping bag Mfr's aim at for that temp range.

This Blizzard product is only equivalent to 3/4" of loft or half what one would want at 45F. That 3/4" of loft equivalency is less than our quilted down comforter that we use on our bed in winter.

I'm not sure the claims of survival are justified. Heart still beating and still breathing come morning? Probably. Functional on one's feet and thinking clearly? Maybe not.

So, it seems that it does turn out that one's clothing and underbody insulation is doing the lion's share of the insulating and this Blizzard product is doing very little to provide any real appreciable warmth in cold conditions. At least, that's how i read it.

If anyone feels that i'm mistaken, please correct me.

I can't see how this could be as warm as they claim. I'd really like to hear from someone who has actually used one. It does sound like it would be dramatically more effective than a normal space blanket, and it might be the best way to carry emergency warmth in a winter day pack (the best insulating method, it doesn't hold the potential warmth of a fire building kit).

The idea I had was to use it to turn a 3-season sleeping bag into a winter sleeping bag with the added benefit of keeping your insulation warm from perspiration. It might be a cheap and light way to beef up a sleep system.

Thank you Richard. Like pj says, paraphrasing, 'show me the EN13537'.
But if this product gets people thinking about contingencies, and prompts people to carry SOMETHING, it might save a few hikers who would have died of exposure.

I remember on my summer time climbs up Mt. Fuji, it was around 30F at the top and many climbers were surprised by the temperature change due to lapse rate, and wore only shorts and tshirts. A few were more comfortable wrapped in their mylar space blankets waiting for the sunrise. It at least cut 100% of the wind.

Interestingly (to me at least), is Montbells similar product, the blizzard bag.. looks like a mylar waffle enchilada.
https://www2.montbell.com/japanese/asp/products/Spg_shosai.asp?cat=1104&hinban=1121654

Edited by Brett1234 on 02/01/2007 00:35:22 MST.

Brett, don't forget to order that MB mylar enchilada with the special "hot sauce"! Caliente!!

Somehow, I suspect that the enchilada isn't microwave safe ;)

Tom

PJ, quite right, I asked my GF to wear nothing but this hat, these socks, cover herself in ehchilada sauce, and climb into the mylar enchilada; but she does not go along with my SUL fetishes! :(

hey, its a slow day at work...

Brett,

You are a sick, sick man. I totally respect that ;)

Tom

Brett, where do you come up with all of these humorous, yet apropos, pics? what's your secret?

Also, i'm glad your GF didn't go for it. I've seen Japanese TV. There are a lot of young Japanese girls that probably would have taken your suggestion IF it was being televised on one of those Japanese TV programs - at least from the little that i've seen (which was more than quite enough, thank you)!!!

pj, I use yahoo or google picture search.. and too much free time at work occasionally.

Actually, to research a new piece of gear I start with yahoo or google pictures of the EXACT item name; usually if a website takes the time to title a picture correctly it leads to a good review! Try it!
Or just look for "chili hat" and "chili socks" pictures..

Yes, Japanese tv is quite strange sometimes; but they are just trying to get viewers eyes onto their ad space. Usually harmless fun, and definitely not "P.C."

Looks like the folks who developed the original space blanket have their own clone version.

http://www.mpioutdoors.com/extreme-tech-data.htm

I don't believe you can do a straight comparison with inches of down loft. This thing does trap significant reasonably still air, but it is also 100% windproof. It also clings to you, reducing air needing to be heated. It also reflects body heat, and provides a vapor barrier. (even the company's testing using a dummy would not account for the evaporative benifit of the vapor barrier).

[CAUTION: Another RANT Alert!]

Again, a company, in my opinion, using numbers to "fake" it and mislead.

The new "Space" bag has twice the thermal resistance of the original Space Blanket. THAT AIN'T SAYIN' MUCH!!! A PD Sweater probably at least 10x or 20x as much (maybe more??? Just guessing here.) based upon how warm it feels.

Here's what, in my opinion, very well could be the misleading part, they claim it has 3/4 the thermal resistance of a heavy full size down mummy bag (heavy down - now there's an oxymoron! Heavy down - no wonder some birds can't fly south in the winter!! Just funnin' here, i know what they're trying to say - their space bag is lighter than a down mummy bag - whoopee! means nothing if it's not warm - hey, cold air is lighter than my WM Highlite!). Hope i never get caught in winter (or spring or autumn for that matter) using a down mummy bag that has only 66% more thermal resistance than the original Space Blanket. How do spell hypothermia? M*A*R*K*E*T*I*N*G*H*Y*P*E*!*!*!

At least they describe how they came up with their results, but, in my opinion, they lead you to believe that it somehow relates to reality. The results are meaningful if a Coroner wants to determine the time of death of the occupant of the various bags. Huh??? Johnson, have you lost it? Here's what i mean: they used a hot water filled dummy. So, what's wrong w/that? The thermal energy in the hot water was used to heat the, initially cooler, trapped air in the mummy bag & then there isn't any more thermal energy being produced. With a living, breathing, heat producing human, thermal energy is continued to be produced even after the bag is heated. The down mummy bag will, from that point on, be far, far more insulative than the Space bag (or whatever they want to call it). This is why mummy bag designers try to walk a fine line b/t a too restrictive girth in a mummy bag and too much air next to the body (which needs to be heated - hence, the success of the MB SS system = the best of both worlds). The Space bag, on the other hand, will probably, IMHO, continue to rapidly conduct away body heat. At least that's how i see it (maybe i'm wrong?).

Again, as far as radiant heat loss goes. It's not even worth considering at body temps, and this inspite of the delta-T that could exist - convective, conductive, and evaporative heat loss is so much larger at body temps than radiative heat loss. Now, at the temp of a burning flame, it's something worth considering - like in a stove windscreen.

Anyways, I've reached EOR. Feel free, anyone, to Post back and correct me wherever you feel i've gone astray from the truth.

[Note: EOR = End of Rant]

Edited by pj on 02/04/2007 02:27:11 MST.

I've been using the Blizzard Bag on and off for a year now. I've mentioned it before (but got bashed for "recommending" potentially dangerous equipment (which it is)).

I've never used it for more than 1 night at a time, as it's too big to use inside my current bag, so I use it as an insulated bivy of sorts. In this configuration, condensation is huge so it's not appropriate for long hikes.

Most recently I used it down to 0 degrees F as an overbag to a Nunatak Arc Alpinist. I believe that the modest 11oz extra weight spelled the difference between being comfortably warm and merely safely warm. It also kept the snow at bay (I was tarpless).

For the price and weight (it is bulky, however) I do recommend people to experiment with it. Perhaps cut it into a quilt. Durability is so-so, mine has developed some little holes in the outermost layer, but nothing major.

I've also taken it as my only insulation (silkweight bottoms and tops as only clothing) in warmer weather, indeed throughout summer in southern Utah anyway it's quite adequate. I was comfortably warm thru September.

Again, condensation is always a factor with this bag, but personally this has never been a huge problem for me and my short hikes, but I am more accepting of it than most.

I intend to use it for VB inside my bag, as well as emergency equipment for a mild season daypack.

As for specs, I fully agree that comparing this to any "real" down bag is a joke, esp. in view of the several centimeters of still air insulation it's claimed to have. Nonetheless, that's still much better than the original blankets.

As for hype, I think it's fairer to compare this ~$25 emergency bag to similarly priced (so-called 3 season) synthetics ----

By the way, while my hardcore backpacking experience is limited, I have great credentials experimenting with emergency blanket/bivvy combinations, vapor barriers, using down sweater combinations instead of sleeping bags etc., dating back to the mid 1990s. Needless to say, though I survived it all without any serious problems or hypothermia, I've frozen my butt off more than once....

PJ says "Anyways, I've reached EOR. Feel free, anyone, to Post back and correct me wherever you feel I've gone astray from the truth." Sorry for my delayed response Paul, but the Blizzard website has been down, and I wanted to check my facts before answering your rant. Unfortunately the site is still down, but I'll go ahead anyway and correct the areas where I feel you've gone astray from the truth.


First, the Blizzard bag and the MPI seem to be the same thing. I understand that MPI recently became major shareholder of Blizzard and will handle US sales. Blizzard say that their own tests produced a result of 9 Tog , but also say that independent tests by Leeds University, who have a very good reputation for testing textiles, said 8 Tog. Now I share your views on the reliability of tests done by manufacturers on their own products, but if Leeds University Textile Department says 8 Tog, then 8 Tog it is. So even if your rant about the tests described by MPI is correct, and I suspect it is, it is irrelevant . Similarly your rant about the insignificance of radiant heat loss at the body temps we are talking about is merely re-iterating what has already been accepted in this thread - that the still air trapped is vastly more important here than the reflection of radiant heat. Even MPI's gung-ho copywriter merely mentions both without describing the relative importance, though he is a touch free with the truth when he describes a 12 Tog bag as 6 Season (15.5 Tog is closer to the truth), and his tables of comparison do not deserve to be taken seriously. The real point is that a Blizzard Bag will provide 8 Tog in a much lighter package than a down sleeping bag, as well as being windproof, waterproof and able to wrap closely round the body.


You and others have been ignoring the fact that neither company sells these things as sleeping bags, but as an "emergency-survival protection bag" (MPI's words). I can't check on Blizzards description while their site is down, but it was much the same, though I recall that they got slightly carried away when they described the survival bag's use in an emergency and probably mentioned that it also acted as a sleeping bag in those circumstances. So EN13537 which is a standard for sleeping bags does not apply. I'll repeat that. EN 13537 does not apply. The only people who deliberately use the Blizzard bag as a sleeping bag are climbers and adventure racers who, in my opinion, are all as mad as a box of frogs and masochists to a man except for Elliot Lockwood and all climbers and adventure racers on this forum.

If you want something to carry in case of emergency you should go for the Blizzard Bag . This will give you a waterproof, windproof, VB lined bag providing 8 Tog (5.16 Clo) warmth for 350 gms (c.12 ounces). It will keep you warm in mild weather as long as you have insulation under you. 9 Tog is recommended for "comfort" down to 0c.(32F), 8 Tog would leave you a little less comfortable at that temperature, but would probably save your life in all but the most severe weather. .. Until you unpack it for use it is about the size of a VHS cassette (remember them?). Sounds a good thing to carry for daywalking at least.