Keeping warm in winter - old technology v new

[Hathor]

Morning all,

We get some long, cold winters here in central Europe and over the years I have collected various items to keep me warm - fleeces, wool, etc. I am not a fan of wool, too itchy for me.

Yesterday morning I headed off to the countryside for a day. Arrived at the bus station early and the bus arrived late. I had 30 minutes waiting in minus 15c but a merino wool t-shirt, micro-fleece and (my christmas present for this year) a Montane extreme smock ket me warm. Into the forest later with the same gear and I was toasty warm. But then I cooled down, added a down gilet and had to wait for the bus home in only minus 8C. I had to march up and down to try and generate some warmth.

Then I remembered the one item in my wardrobe which has endured minus 20C plus windchill and never let me down - a heavy, old sheepskin coat.

I am interested to know what gear / materials / combinations other folks use to stay warm? And to what temperatures and whilst doing which activities? This can include everyday activities and not restricted to bushcraft stuff.

Many thanks,

Jon

[FishyFolk]

First off, you say you got warm, and then you cooled off. And I can see why. I always bring a thick fleece or wool sweather in my back pack. But dress more or less like you when I am moving about and in activity. If I sit down for a rest or to have a brew, on comes the thick sweater to keep me warm. I prefer the wool because it keeps me warm even when wet...

Also I use a jacket with plenty of ventilation options. So mine has zippers under the armpits, and in the sides that I can open up if I get to warm. The trick is always in regulating the heat. That is also the purpose of dressing in layers. So you can shed one if you get warm/ break out a sweat, or to add one or more if too cold.

Else if you don't already have a headover, get one. 50% of your body heat is lost trough your neck and head. Also it can be pulled up to cover your ears if it gets windy. It does really make a difference, even if you allready wear a wool hat and your jacket has a nice, snug hood.

[KaiTheIronHound]

Wool and oilskins. I dont like the flammability of newer stuff to be honest, plus as a uni student i cant afford it. Basically i dont spend small fortunes on lightweight uber-mega-super-space-alien-techno-fabrics! Op shops all the way gents!

[paulthefish2009]

If its cold I start out with a cotton t shirt and boxers then thermal long johns and a lumberjack type shirt. Next up i wear long wool hiking socks,combat type trousers then it's on with my leather walking boots. On top I normally wear my quilted barbour with a waxed cotton fleece lined cap(with ear flaps). If its wet and/or really cold i put on (over the top) my waxed cotton barbour jacket and waterproof and fleece lined "force 7 " trousers. I also put on a pair of fingerless gloves. If it's warm then it's baggy arsed shorts,t shirt and my tilley hat! Paul

[comanighttrain]

Synthetic...most of my gear is synthetic. I'm quite active when out so lightweight and breathable is quite high priority. As for flammability it is a problem... I have quite a few melt holes in my trousers from embers flying off the fire. it's not a huge problem though.

[Marvell]

50% of your body heat is lost trough your neck and head.

Wanna cite your source on that? I find it hard to believe that an area that represents around 12% of your body can be responsible for that much heat loss. I'd be very much interested in the original research.

[Marvell]

My temperate cold weather consists of:

Merino Thermals
Lined Craghoppers (though they are not my favourite)
Bridgedale Summit Socks (unless I'm walking far, in which case I use less thick wool ones)
Trespass close fitting fleece
Rab double pile fleece
Windproof jacket (nothing special, hardly use is)
Northern Ireland gloves (for use)
Overmittens (for warmth)
Scrim scarf
Thinsulate hat

[CanadianMike]

Wanna cite your source on that? I find it hard to believe that an area that represents around 12% of your body can be responsible for that much heat loss. I'd be very much interested in the original research.

Always been a well known issue, now it seems like it's a myth...... :S

http://www.guardian.co.uk/science/2008/dec/17/medicalresearch-humanbehaviour

[comanighttrain]

I did think it would be "if your wearing clothing then x is lost from your head..."

[FishyFolk]

Wanna cite your source on that? I find it hard to believe that an area that represents around 12% of your body can be responsible for that much heat loss. I'd be very much interested in the original research.

It's what professional survival instructors like you have been telling me over the years.
I assume it's when wearing clothes, and not covering your neck/head. Leaving that the "only" route for body heat to escape the confines of your clothes...

It's pure logic. The part of your body not covered with clothes, is the part you will lose most heat from.

[Marvell]

It's an over quoted and badly used statistic. The truth of the matter is that the body will lose heat at roughly the same rate by surface area of skin, but this itself has caveats associated with blood flow and body responses. The myth is that the head of a naked bald man loses heat at a significantly greater rate than other parts of the body. This is simply not true and was based around the number of blood vessels in the scalp and the restricted regulation mechanism the body has there. Those that then try to generate a statistic associated with the clothed or partially clothed man are ignoring the thermal properties of the clothing being worn and such figures as 45, 50, 35 and even 70 percent are bandied around. The original post seemed to be using the mythstat or was making one of these assertions. In addition, time is hardly ever taken into account, nor ambient temperature. Also, unless you're bald, our heads already have insulation, in the form of hair.

Ultimately, we have to lose heat by some form or another or we'll get hypERthermic. Yes, we're going to be losing some of that, clothed or otherwise, to the air, but if we cover all of our body in super thick down and then try walking around, we're going to boil. If there were such a thing as total thermal insulation and head was the "only" place to lose heat, it would be losing it at a huge rate (highly dependant on context), and that's just not true. The body can only lose so much heat through all mechanisms available and so if it's not losing it fast enough, it'll actually vasodilate inside your clothes to increase heat loss there, even though it's thermally insulated. If it's not losing it fast enough even then, it'll sweat.

The supposition that you must wear a hat is meaningless outside of the context of activity. I have seen many a student chopping wood in the snow wearing a hat sweating like crazy, simply filling up the lovely airy insulation they are wearing with water, a highly heat conductive material, which then can't evaporate as it's lodged in lower levels of clothing. Even walking around generates extra heat which we have to account for.

From a burn evaluation perspective, the head (not including neck) represents 9% of the average (not obese) adult total body surface area. This is the same as an arm. If we say that the neck is about half that again, then we might say that the head and neck total is representative of both arms covered over the shoulders, like someone wearing a t-shirt length top. Interestingly, it is said that the brain produces 16% of the total heat generated by the body, so with an external surface area of around 3% of the body, it seems like losing heat through the head isn't such a bad thing after all. (How's that for mucking about with stats :) )

Irrespective of the science, I assert that I would rather be out at -10 with no head covering than no arm covering and a balaclava.

It is not wrong to say that a hat is good for lowering heat loss though the head, but beware of wielding statistics out of context. Who gives a monkey's if we lost 1kJ of heat through our head which represented 50% of total heat loss if the core body temperature remained the same? It is correct to put on a hat if you're getting cold, but I've been out down to -36 and if I'm even slightly active in the kind of clothing I use there, then I'm not going to be wearing a hat and I'm going to be ventilating my clothes. Context is everything, but the ultimate goal is thermoregulation, so that should be the starting point of an evaluation of hat requirements.

I hope the this and my previous responses have seemed aggressive or terse, but as a mathematician, I am wary of the use of "bad statistics" and tend to make my point quite ... erm ... well, you know. So in case I caused any offence, the next round's on me, how about that?

[FishyFolk]

Perhaps a more correct assertion would be that given you are wearing wind proof clothes, the most warm air, trapped inside your clothes, that keeps you from losing body heat is lost trough your neck. Not the actual body heat. Thats why a scarf or headover is a good idea. Assuming it is still correct that warm air rises, and cold air sinks.

Else, thanks for the lecture....

[Marvell]

The passive convective process of warm air leaking out of the neck being replaced by cold air being drawn in through cuffs and waist overlap does happen, but does not rely in you wearing wind proof clothing. Yes, you're right, this is not a direct loss of body heat, rather an indirect loss since your clothing now contains cooler air which increases heat loss locally. If you're cooling down and need to prevent this, then you have to attack the problem from both ends, not just the neck. There should be no reason to have moist air inside your clothes, in fact it has quite negative effects, see the above lecture :p

[Whistle]

Nice myth busting Mike and Marvell ... But it still feels like more than 50 % when you are as bald as me and caught hatless !!!

This year I even invested in a new cycle crash lid with fewer and much smaller and adjustable vent holes , open'em for slight cooling and close'em as soon as it gets chilly again !!!

The trouble is your brain still demands a high proportion of the bodies general blood supply and even though your body can close off peripheral capilleries to save heat it cant cut off your brain's blood supply , so in extremis , going without appropriate headwear can be just as dangerous as not wearing appropriate footwear !!!

Sorry Marvell !!! Missed the definitive lecture notes supplied in your post while I was writing this ... well done !!!

Cheers Whistle

[FishyFolk]

Well, well, I'll still plonk my wool hat on my head and headover around my neck when I feel cold. Else my jacket as well as trousers have plenty of ventilation options and I dress in layers, so I don't worry much about moist air getting trapped inside. It's a case of opening couple of zippers and letting it out once I do something that gets me to warm, or simply taking the hat off and stuffing it in my pocket.
Basically I dress the way the army thought me, and it works for me. And a headover is in my opinion a very good piece of clothing when it comes to keeping you nice and warm...

[AdrianRose]

Getting back to the original question in the thread, in winter I use a Buffalo Special 6 smock jacket.

I have been out at -19c with nothing on underneath (except a hairy chest) and have been as toasty as I would have liked to have been.

Cheers
Ade.

[Marvell]

so in extremis , going without appropriate headwear can be just as dangerous as not wearing appropriate footwear !!!

Actually, I think you'll find that heat loss through conduction to the ground ... I'll get my coat :)

[comanighttrain]

Synthetic...most of my gear is synthetic. I'm quite active when out so lightweight and breathable is quite high priority. As for flammability it is a problem... I have quite a few melt holes in my trousers from embers flying off the fire. it's not a huge problem though.

In an update to this, in future ill be carrying one surplus top layer for fire sitting.... thankfully my synthetic jacket was a cheapy one! would be a bit more upset if was expensive!

[Silverback]

Mmm missed this thread, glad I did too otherwise I may have had to put my medics hat on (see what i did there?).

[paulthefish2009]

Sapper,be interesting to read your thoughts on this. My own personal opinion is to always wear a hat when out,Ican always take it off if I get to warm but I can't put one on if I feel chilly if its hanging up at home. Paul

[Bastoss]

Always wear a hat. stops sun burn and in cold weather stops heat loss through my thatchless scalp. Usually go out in a softie shirt. have had a couple now and cant find anything to beat them. when round the fire I wear a DPM smock over the top. Trousers wise I'll go with the encyclopedia and side with the lined crag hoppers or in extreme cold the softie trousers work darn well too.

(Too many cold summit checkpoints on hikes to marshall in Yorkshire)

[Bastoss]

I hope the this and my previous responses have seemed aggressive or terse, but as a mathematician, I am wary of the use of "bad statistics" and tend to make my point quite ... erm ... well, you know. So in case I caused any offence, the next round's on me, how about that?

Factually brilliant but I think you ran fowl of grammar towards the end. Unless you actually were aiming for aggression? As a linguist I tend to pick up on these things.... ;-)

[Silverback]

As a linguist I tend to pick up on these things.... ;-)

Are you a cunning linguist ? ;)

[Bastoss]

As a fox. Sapper, do you have experience of the softie tackle? Whats your take on it compared to the more traditional kit out there?

[Silverback]

Sapper,be interesting to read your thoughts on this. My own personal opinion is to always wear a hat when out,Ican always take it off if I get to warm but I can't put one on if I feel chilly if its hanging up at home. Paul

My theories and thoughts are no different from those printed and published in various books/papers by eminent and informed physicians, medics, paramedics, underground medics et al. My main text books are Casualty Care in Mountain Rescue and JRCALC 2006 (waiting for the amendment)

If you're hot, remove layers including your hat, if you're cold add them. Steve is perfectly correct....wet people (incuding sweat) lose heat faster than dry ones...up to 25 - 27 times faster (dependent on whos research you read).

We deal with as many Hypothermics in summer as we do in winter (statistics again sigh) and currently a friend of mine is writing an article currently based on a hypothermic patient found in near collapse, shivering uncontrollably with an axillary temp of 33.1 deg C. He was indoors with full body cover (no hat ;)).

There is NO way you can lose 50 - 75% of your body heat through your head, Steve is correct again, Normally!!

The head only accounts for about 9% of the bodies skin surface, however your head is very vascular, it also contains the bodies thermostat. The body has autonomic functions which it will protect at the cost of other functions regardless, one of these is to protect the brain and keep it adequately perfused that said the blood flow to the brain does not change as its demand for oxygen is constant unlike other organs. As a result, when you look at total heat loss, the head accounts only for about 7% (when at rest) of heat lost.... less than an arm if we are using 'rule of nines'.

However there is research (by the military) to support that up to 55% of body heat can be lost TEMPORARILY during exercise through your head. Now then normally this isnt an issue as its part of thermoregulation, and the percentage drops to the normal 7% when sweating begins. Heres the rub, a shivering hypothermic patient isnt at rest.....they are shivering (exercising) to generate heat as part of thermoregulation, so in theory they can lose up to 55% through the scalp and as sweating isnt going to commence this loss goes unrectified.

The difference is that the shivering hypothermia patient is indeed exercising, but they do not vasodilate the peripheral circulation; the shivering muscles increase metabolic demand and cardiac demand so the patients do increase their cardiac output; therefore, they do increase cerebral circulation; therefore, they do increase the percent of heat loss through their head....or according to that research ;)

Bung on a hat...problem solved...if only it was that easy.


Get ahead carry/wear a hat. I carry several hats all year round, one and a spare for me and one and a spare for casualties.

Dont forget to watch out for the umbles in suspected hypothermia cases. Stumbles, Mumbles, Grumbles and Fumbles

http://www2.warwick.ac.uk/fac/med/research/hsri/emergencycare/prehospitalcare/jrcalcstakeholderwebsite/guidelines/hypothermia_2006.pdf

Can I add that I AM NOT advocating one bit of research or theory against another. I do however have to work to a series of guidelines from national & international steering groups and representative bodies..... that have been proven to work... ;)

[Silverback]

As a fox. Sapper, do you have experience of the softie tackle? Whats your take on it compared to the more traditional kit out there?

I like the softie stuff, I have a doss bag and jacket. Problem with the doss bag, like all doss bags for me (with the exception of 58 patt) they DONT FIT !! I'm too broad of shoulder

[Bastoss]

Fair call, my light softie bag is a bit narrow round the shoulders but the heavy one thats good to -12 is really comfortable. one of the best night's sleep I've had coupled with a DD hammock and carry mat. Guess Prop forwards have the same problems the world over.

[Silverback]

Guess Prop forwards have the same problems the world over.

Mmm have I played against you ?

[Bastoss]

Possibly but I was only in the thirds at Ilkley, My mate Fred has been a 1st team prop for a long while. Which team were you in? (Scuse the digression)

[Silverback]

Havent played since secondary school...LONG time ago

[Kernowek Scouser]

There should be a support group for former prop forwards with shoulders too broad for standard sleeping bags.
Expanda panels are the way forward!

I always carry a thinsulate hat and gloves in my pack (or coat if I'm wearing one) No idea about the science on this one, but if I am cold, wearing them makes me feel warmer.

[Silverback]

There should be a support group for former prop forwards with shoulders too broad for standard sleeping bags.
Expanda panels are the way forward!



Hear hear. The science around hypothermia is really cool (pun intended) its our deadly enemy, but is also very useful in certain applications

[Old Guard]

Hmmmmmm, so if I have taken all this in correctly, the next time I feel warm, I can leave my hat on and take my trousers off, as this will have the same effect.

Clearly, that depends on where I am at the time. If I was in my local park in the winter, then I would also need a good defence lawyer, when I come up on 'Flasher' charges :-0

[Silverback]

Hmmmmmm, so if I have taken all this in correctly, the next time I feel warm, I can leave my hat on and take my trousers off, as this will have the same effect.

No because each leg is worth 18% (9% anterior and 9% posterior), then there's your buttocks which are worth approx 4.5% so thats a grand total of 40.5%..... not forgetting your genitailia and perineum which are worth 1% (disappointed ?..... I was too) ;)

Mind you it will have a warming effect when given your blanket by the custody officer ;);)


LOL

[paulthefish2009]

To be serious for a bit(bloody rare for me!) I have found this really interesting,just like to thank marvel and sapper for some good info. Paul

[Silverback]

To be serious for a bit(bloody rare for me!) I have found this really interesting,just like to thank marvel and sapper for some good info. Paul


Great. Environmental health issues are a bit of a 'pet' subject. Bit like Steve I tend to find myself out in weather most people stay at home in, bringing home the ones that didnt ;)

[Hushwing]

aye hear hear - good info.

Scouser - I always thought you were the same wee height as me and just stood on a box in your pic!!! ;) (PS Played hooker - tried american football for a couple of years until got tired of becoming the ball all time).

[paulthefish2009]

Thats what I love about this forum,one of you lot always has some sensibal advice when it comes to the serious stuff,cheers chapsT^

[Hushwing]

"SEAGOON:
And you, you must be my uncle, Laird McGool.

McGOOL:
[Talks with bagpipe music] Come in lad, you must be cold, you must be cold. Put on this porridge, come in. Come in and warm yourself by this roaring candle.

SEAGOON:
Ah, thank you, uncle. Real regal Scots' hospitality. Tell me, Mc uncle, why have you brought me to Mac Scotland?

McGOOL:
[Talks with bagpipe music] The truth is, Neddie, I've no heirs left.

SEAGOON:
I've gone a bit thin myself"

The Treasure in the Lake
The Goon Show