Water and Keeping the Human Body Warm

How many of you have ever heard of Gerry Cunningham? Gerry opened a company that you may have heard of in the late 1940?s after WW2 name GERRY OUTDOOR PRODUCTS located in Denver, Colorado. The company produced tents, backpacks, clothing and sleeping bags; insulated with down. Gerry whom I got to know was in my opinion the father of the camping industry. There were young men who worked for him and eventually opened their own companies the most notable was George Lamb who opened Alp Sport that also produced tents, back packs, sleeping bags and clothing down insulated. George then opened a second company Alpine Designs that produced skiwear. George in my opinion was the most creative designer in the industry at that time and his designs still live on; the Wiggy?s Antarctic parka as well as several other garments were his designs and the basic pattern for all of the Wiggy sleeping bags were his original design. I have a debt of gratitude to both of these men since I learned quite a bit from them and I attribute some of the success of Wiggy's to their tutelage. Gerry is his retired years had a sail boat anchored in San Carlos, Mexico in the Sea of Cortez. He used my Nautilus bags on his boat and if he had been in business at the time I am sure he would have been a customer for Lamilite.

Gerry wrote a booklet that I have referred to in the past since I use it as a reference book for clarification about "How to Keep Warm" which is its title. It was published in 1971.

I made two videos that are on the web site, one "the myth of waterproof breathable" and "why you need fishnet long johns." Both videos concentrate on the dangers of retaining the moisture that your body naturally produces. In the section of the booklet Gerry references the topic "Evaporation" he states the following: "sweating should be avoided like the plague", "sweating is a means of losing heat from the body", "water vapor in clothing is a problem because it can destroy the insulation efficiency", "a certain amount of vapor is unavoidable, but to compound the trouble by sweating is a cardinal sin when trying to keep warm". He is talking about being in a cold environment so he references a typical situation. "First you sweat and as this evaporates from your skin, you lose both the heat of the moisture (the moisture as a vapor comes out of your pores and it is warm and it condenses to a liquid), and then you lose the latent heat (latent heat is the name given to energy which is either lost or gained by a substance when it changes state, for example from gas to liquid). In this case it has changed from gas (vapor) to liquid."

Now he says something of even greater value: "this gives you immediate relief from the temporary heat stress (he means activity that caused the sweating in the first place) that triggered the sweating. Unfortunately, you are going to get more relief than you bargained for. This water vapor (the evaporated sweat) starts to migrate through your layers of clothing. Eventually it reaches a layer that is below the dew point temperature and it condenses and wets this layer. Here it liberates its latent heat and, because it is close to your outer clothing layer, this heat goes mostly out into the air. Your clothing slowly wicks back the moisture to your skin where the latent heat is once again drawn from your body to evaporate the moisture all over again. This happens perhaps an hour after the initial heat stress situation and probably during a period when you want most to conserve heat." [The moisture that has stopped moving away from you has now started to move back towards you resulting in a buildup of moisture which does in fact draw heat from you. This is a circular action.]

As you can see moisture produced by your body is your number one enemy. Since controlling that moisture is impossible, you cannot stop the rate of moisture coming through your pores, you must take steps to help eliminate the moisture while it is still in a vapor state, and that means the best first layer to wear is the fishnets. Over the fishnets you should only wear lose fitting vapor permeable garments. For years I have been advised by my customers that they would get into my sleeping bags wet and be dry in the morning and I really had no explanation, and now I do. All of the materials used for the bags are vapor permeable and the moisture from your body while in the bag is traveling through the materials because the heat from your body is retained within the bag itself. Since none of the materials has any capacity to absorb the moisture the first dew point that the moisture reaches is outside the bag. The same thing occurs when you wear Lamilite parkas. If you are using a down bag or are wearing a down filled parka there is a dew point within the down so it will ultimately trap the moisture and you will experience what Gerry has described above, and the result is you are getting cold.

Do you understand why your feet get cold? Feet have 500,000 sweat glands and can produce more than a pint of sweat a day. With that much moisture being trapped inside your foot wear, if it happens that your foot wear is lined with products like Gore-Tex and or Thinsulate which prevent the moisture from getting out of your foot wear, that is why you have cold feet.

What it boils down to is how best to allow, not inhibit the moisture that is constantly flowing out of the core of your body to the skin surface to get away from you so it does not have a negative effect i.e. cause you to get cold. Fishnets and only vapor permeable lose fitting layers over them.

At the time I am writing this article the winter Outdoor Retailer trade show is taking place. They published an article "Outerwear doesn't stop improving" written by a photographer who has zero background in the field of insulation or textiles in general for that matter. But that doesn't stop him from spouting off about materials used for insulation that will work quite well in south Florida in July; such as the various names Primaloft uses for their product, I say product since from what I see on their website they have one product and various names for it. He further writes about down that has a water repellent treatment applied to it. How about Polartec claiming they have the "first-ever breathable puffy insulation". I do believe that the Lamilite that I have been making for 40 plus years has demonstrated how efficient is has been and continues to be as a vapor permeable puffy insulating medium. Maybe their product is alive so it can breathe. Then he writes about 3-M's Thinsulate featherless down as if it were already being used which I do not believe is the case. I have yet to know of any company that is using it, but there may be one. The one aspect of the article that I found of most interest is the fact that all of the companies selling these garments are talking about better ways of moving moisture through them. From all that I read about these outerwear garments the title of the article should have been; "OUTERWEAR THAT HAS STOPPED IMPROVING". For one and all who buy these garments next winter remember that you are buying a new style or color but they are for late spring and early fall not winter as the companies suggest.

BUYER BEWARE