9 December 2016

Cold and Wet in Expensive Long Johns

Brian Farnworth, Some Practical Advice on Cold Weather Clothing; Technical Note 89-21 (Ottawa: Canadian Defence Research Establishment, 1989), p. 2:
There is a lot of hoopla in advertisements and newspaper articles about some types of materials being better than others. It is usually claimed that because a certain fibre is very fine, or hollow, or natural, or the product of space age technology, that it does the best job of keeping air still. None of this is true. Pretty well all clothing materials do a very good job of keeping air still (as long as the wind doesn't blow through them). A 10 mm thick layer of clothing creates a 10 mm thick layer of still air no matter what the fibres are made of or what shape they are.
Ibid., pp. 8-9:
No one has ever demonstrated that wicking fabrics next to the skin have any significant effect on warmth, coolness, wetness or dryness. Many people claim that they feel more comfortable in polypropylene than in cotton.... But then anyone who pays $50 for a set of underwear is not likely to admit he's been taken. The scientific evidence to date says that if you sweat into cotton underwear, you have wet cotton underwear. If you sweat into polypropylene underwear, you have wet polypropylene underwear. The water will not wick away. It may be that you'll find one more comfortable than the other, but neither one will be insulating if it's wet. 
Hat tip: WoodTrekker