I've always carried one of those large orange polyethylene survival bags. If you're immobilised, the fact they're totally water- and air-proof keeps you much warmer than just your jacket etc. I've come close to using one, too, when my knee-cap dis-located in Cwm Idwal, but I managed to crawl out. It was touch and go though, and the weather was foul.

But these days with mobile phones and excellent MRTs casualties are usually rescued in a matter of hours. Is carrying the bag (fairly heavy & bulky) necessary? Do you carry one?

I think I'd always carry one if I was going somewhere remote like the Highlands, but around Snowy I don't think I need one really, providing I still had a w/p jacket, o/ts and fleece. If I were immbolised with neither extra clothing nor a bag, I don't think I'd last too long...

yeah i carry one, but mostly as a large waterproof thing to sit on at lunch time! also makes a great sledge!

And TBH at the price they are and the size its really not worth not carrying one!

They also make a good thing to put between dry gear n the wet jacket youve just taken off in your sack!

Mine always lived at the bottom so getting it out to sit on was too much faff.

Thinking about it, they work by being impervious to air and water (they have no intrinsic insulation value). So I thought 'what else has those properties'? After dismissing clingfilm and not knowing a manufacturer of giant condoms, I realised one of those little foil space blankets would do the same job (assuming it's a bag, not a blanket).

On the other hand its big and orange so if you have to be rescued its very visible. I agree that most survival bags are over thick for a single-use disposable item (you hope!), they could be a lot thinner to do the job and the smaller size and weight would mean less of a reason not to carry one.

I always used to buy kit that was brightly coloured for "safety" reasons but a lot of new stuff is in subdued colours. I wonder if there are any real safety implications?

I carry one. Ben's right - they make excellent sledges and are handy to sit on. I reckon it's worth carrying one for safety too - although obviously this depends where you're going and all that.

Yep always carry one, only time I've had to use it was as a goundsheet protector when camping on some rough ground.

BTW it's generally accepted that foil space bags are useless in mountain hypothermia situations.

A wise man once said; "It's better to have and not need than need and not have."

Here endeth the lesson.

Oh, and as well as keeping your bum dry and making a great sledge, they're also a good makeshift "footprint" if you happen to be camping.

Whoops! You beat me to it Mike. Great minds and all that.

I always carry one (unless I've got my tent with me), and when speaking to MIA's they've said that foil space bags are next to useless. I know that there have also been moves (unsuccessful until now I think) in the fell runners association to a make a survival bag a compulsory piece of kit.

Yes, the only time I really have used mine is as a sledge. But I can always pop it in for the snow.

Mike, as I said these bags work by blocking the movement of water and air - cutting out heat losses by convection, and by trapping vapour that would otherwise pass through w/p clothing carrying energy with it. With a vapur barrier, the vapor condenses on the inside of the barrier and releases it's latent energy as heat in the process. That's partly why Arctic adventurers use vapour-barrier sleeping bag liners (plus stops moisture reaching the down) and socks. As such, any impermeable barrier will achieve this - whether aluminuim foil or plastic.

I used to carry one but tend to take either a group shelter if not going on my own or a Rab survival zone bivvy bag which packs down fairly small and not too heavy either. I still give out the orange ones to youngsters when we go out and would certainly not let them go out without one. I also carry a foil space blanket which weights nothing as an extra bit of kit in my first aid kit.

We posted at EXACTLY the same time!

freeky!!!!!!

Interesting competition, spend a night in the mountains you wrapped up in some baco foil, me in a placcy bag, see who survives till morning.....

Incidentally, I got rid of my foil bag some years ago after hearing mountain rescue teams and others decry them. It was a good job I did, when I opened it, the damn thing had deterated and it just fell apart!

Foil bag - imprevious to water,etc. Plastic bag - impervious to water etc.

So why do they tout the orange placky thing and decry the foil bag?

Mike D I also had this happen with a foil blanket unfortunately it was when it was needed most but also had an orange plastic bag so major disaster was avoided. I now tend to replace the blanket every 12 months just in case as I still think they are worth carrying as a spare incase of the unthinkable.

Space blanket style bags are much easier to tear, thus renderng them useless.

They would also flap around more, but whether this would have any implication for survival use, I have no proof.

I'll stick with my orange survival bag for now thanks all the same.

Si(C)

The only time I have heard anyone pronounce on this issue they claimed that in a high wind the more rigid orange plastic kept the wind off better, avoiding the windpump (I kid you not) effect of a very flexible foil bag. I'm not sure this would make much of a difference but I can't think of a better reason other than durability.

Thats kind of what I eas thinking when I mentioned the flapping around. I think it WOULD make you feel colder, but as to how much it would really matter...? Lets hope I'm never in a position to find out!!

Si(C)

I used to slate foil bags too, but I've just been thinking about it. True, they tear as well, which would be a bummer. Wind-pump is a good point too.

The rate of conduction of heat must be huge for both, so it can't be insulation, as such..

I suppose plastic is prefered because it's tougher (but heavier)? That's always the trade-off with lightweight gear though, isn't it.

Spending time in one and then the other would be an interesting expt!