Clothing Definitions — definitions of garments and clothing terms from Apparel Search
Cold weather boots are specialized combat boots designed to protect the wearer's feet from cold injury and frostbite. They feature thick thermal insulation, and may be white rather than black in order to blend in with snow and ice. In the United States Army, Type I Extreme Cold Weather Boots are designed for wet or dry conditions down to -20F (-29C), while Type II boots are suitable for dry conditions only down to -60F (-51C). This page explains why the wet-versus-dry distinction drives the two designs, and how insulation, vapor management and fit keep feet working in extreme cold.
Cold weather boots are specialized combat boots designed to protect the wearers feet from cold injury and frost bite. They feature thick thermal insulation and may be white rather than black in order to blend in with snow and ice.
In
the United States Army Type I Extreme
Cold Weather Boots are designed
to be worn in wet or dry conditions
down to -20F (-29C). Type II Extreme
Cold Weather Boots are suitable
for dry conditions only down to -60
F (-51C).
| The above article is licensed under the GNU Free Documentation License. From Wikipedia, the free encyclopedia (https://en.wikipedia.org/wiki/cold_weather_boot). Modified by Apparel Search 1/18/06 |
The enemy in cold weather is moisture as much as temperature. A working foot sweats even in deep cold, and if that moisture migrates into the boot's insulation it destroys the trapped-air layer that provides warmth — and at the lowest temperatures it freezes there. The two army types answer the problem differently. The wet-or-dry Type I boot is built to keep external water out and let the boot be dried in the field. The Type II boot, for dry cold only, seals the foot inside a vapor barrier so sweat never reaches the insulation; that is what allows a rating to -60F, at the price of feet that stay damp inside the barrier and must be aired and dried at every halt.
Fit is part of the thermal system. Cold weather boots are sized to be worn with heavy sock systems and a little air space around the toes, because a tight boot restricts circulation — and it is warm blood reaching the foot, as much as insulation around it, that prevents frostbite. Lacing snug at the ankle but not tight across the instep is the field rule that follows from that physiology.
Cold weather boots are specialized combat boots that protect the wearer's feet from cold injury and frostbite. Thick thermal insulation is their defining feature, and they may be made white rather than black to blend in with snow and ice.
In US Army terms, Type I boots are designed for wet or dry conditions down to -20F (-29C). Type II boots are suitable for dry conditions only, but protect down to -60F (-51C) — the extreme rating is bought by a vapor-barrier construction that must be kept out of wet use.
Insulation works by trapping dry air; once insulation is soaked, it loses most of its warmth and can freeze. Boots for wet cold therefore concentrate on waterproofing and drainage of sweat, while boots for dry extreme cold can use a sealed vapor barrier that stops foot moisture reaching the insulation at all.