CLOTHING FOR OUTDOOR
COMFORT AND SURVIVAL
by
Tom Richardson
September, 1995


Humans are a tropical animal with a need for an environment that will allow them to maintain a constant body temperature of about 98.6 degrees F. At any ambient temperature less than 98.6 F. a human constantly looses body heat and may become hypothermic (reduced body temperature). A reduction of body temperature of only 3 to 5 degrees will cause impaired body function and diminished thought process. Otherwise healthy young adults have died from reduced body temperature here in New Hampshire in weather that never dropped below 70 degrees F. Similar increases in body temperature (hyperthermia) are at least as serious and can cause brain damage, convulsions and death (heat exhaustion and heat stroke). Personal comfort-discomfort is of significant importance to search and rescue personnel and outdoor enthusiasts due to the fact that a human that is not physically comfortable is not able to concentrate on any subject other than his or her discomfort. Lack of concentration and diminished decision making process have been directly related to many outdoor rescues and deaths.

So how does a mere human maintain comfort and survivability in a hostile environment? Proper nutrition, constant fluid intake and a survivable micro-environment directly around the body will provide comfort and the physical and mental ability to function as a productive team member rather than become an additional burden or patient. The proper micro-environment is created and maintained by the proper selection, maintenance and use of specific types of clothing. A vast and often confusing selection of new and used outdoor clothing is available to allow you to create a suitable micro-environment system for all potential weather conditions. Whether you invest $200 or $2,000 in your system the same basic principals and rules apply. Functionality when wet, easily changed layers and complete coverage are the basic important rules.

A $500 parka will not keep you alive if it is not accompanied by a $10 hat! Two $4 pair of socks may do more to prevent blisters than one $30 pair. The "weakest link" theory definitely applies with outdoor clothing systems.
A basic outdoor clothing system consists of three layers of clothing that will wick moisture (perspiration) away from the body, maintain its insulating value when wet and repel rain and wind. Cotton and cotton blend fabrics have none of these qualities and will hold chilling moisture against the skin. A wet person looses body heat about forty times faster than a dry person. COTTON KILLS!!! The only natural fabrics or materials of interest in safe outdoor clothing are silk for underwear, wool for warmth and leather for durability. Various synthetic fibers have much more desirable characteristics. Polypropylene for underwear and warmth and nylon for outerwear dominate the outdoor clothing market. Several modifications or versions of these materials are produced by numerous manufacturers. Advertising claims and hype by the fabric and clothing manufacturers add to the confusion of customers. Finally, methods of garment construction and use features are just as important as the materials that are utilized.

All of this may mean more if you have a basic understanding of the physics of moisture transportation. Water vapor (moisture) has a physical quality of desiring to move from warm moist areas (next to your sweating body) to cool dry areas (typical winter air). Thus, IF the surrounding atmosphere is relatively cool and dry (common winter weather) the moisture produced by your sweating will attempt to move to the surrounding atmosphere. This is generally desirable. If the surrounding atmosphere is cool and wet or warm and wet this basic law of physics will not benifit you. Body sweat or other moisture will not transfer efficiently to high humidity air (rainy or foggy day or humid summer day). Clothing insulation that is too thick may slow water vapor transfer and be cold enough in its outer sections to allow transferring water vapor to condense and freeze in the insulation or inside surface of the waterproof or waterproof-breathable outer garment. This is a serious problem and is a principal reason for several thinner layers of insulation instead of one thick insulating layer. Add or subtract layers as needed to keep the system functioning properly for the ever changing conditions of activity and weather. Brief stops for layer changing and clothing tune-ups should be common during outdoor activities. If possible control your activity to minimize or eliminate sweating. Being just a little bit cool is better and safer than being sweaty and wet.

You will never be comfortable with itchy, clammy, wet and/or constricting clothing that is "close and personal" with your body. Cotton may be fine for hot and dry conditions when sweating and hypothermia are not a safety concern. The rest of the time you need soft, smooth, stretchable fabrics that transport moisture away from your body and quickly "wick" this moisture to the atmosphere or next clothing layer. These features keep your skin and underwear reasonably dry and comfortable. Polypropylene fabric is excellent for this purpose and is available in several weaves and trade names. Socks, underpants, tee shirts and several styles of long underwear are available in light, medium and heavyweight. For most situations, particularly when any form of activity is involved, light or medium weight is suitable. Heavy or expedition weight is suitable only for warmth with minimal activity and extreme weather conditions.

The next, and usually thickest, layer is the actual insulating layer. It's the purpose of this layer or series of layers to maintain a quantity of dead or very slowly changing air around your body. It should be understood that the "insulating" fabric does not prevent heat loss. The thick, "puffy" fabric is a method of maintaining dead or still air that is in turn a poor transfer agent for heat. Thus, the limited movement of the poor heat transfer agent (dead air) minimizes the transfer of heat away from the body. No clothing produces heat for the benefit of the body. When wet, cotton and down hold heavy moisture and mat down and clump, thus loosing the all important air space. Polypropylene (fleece) and polyester (fiberfill) are plastic fibers that do not absorb or hold signifigant moisture. They do not become heavy and matted or clumped. They continue to maintain air space when wet. They also dry very quickly, even while being worn.

Wind and rain will quickly pass through insulation and underwear layers. To repel these common but deadly forces requires an outer layer that is impervious to wind and rain but allows the internally produced moisture (perspiration) to escape. This outerwear layer is the most expensive and technically advanced portion of the micro-environment system. These garments themselves may be constructed with up to three layers of material. The layers include an outer durability layer, a middle breathabe-rain and windproof layer (Helly Tech, Gor-Tex, Ultrex, System III) and an inner comfort layer. These relatively expensive garments are desirable but are not magic and do not function as well in all conditions as the manufacturers would like to have you believe. Non-breathable outerwear is available for lower cost. During moderate or strenuous activity moisture builds up inside non-breathable garments, leaving the wearer and her/his clothes soaking wet. However, in truly miserable weather conditions these non-breathable garments will offer better protection from heavy rain, wind and wind driven rain or snow. The outerwear garments frequently include "technical" features including several zippered pockets, hood, waist and wrist elastic or straps (for wind proofing) and arm pit zippers (for improved ventilation).

Boots are another matter. The popular heavy duty sneaker/fabric hiking shoe are comfortable for easy day hikes and everyday use. They do not provide suitable foot and ankle support for moderate of heavy duty hiking. They provide no protection from rain, puddles and wet ground cover. Strong, durable hiking boots are necessary for any thing more demanding than a short off road hike. Leather is the dominate material. Plastic inserts provide additional foot support. A deep lug Vibrum sole is a bit tough on some terrain but is a necessity for traction and safety. Leather can be waterproofed, however it is not sufficiently breathable and dries very slowly. Bring extra socks and change as needed (clip damp socks to the outside of your back pack for drying). A good sock combination includes a thin wicking liner sock against the skin and a thick insulating and/or cushioning sock. Feet demand and deserve constant attention and care, when a foot has a minor problem, you have a major problem-limited mobility! For light or moderate winter use the Sorrel type boots are adequate, however, consider having an extra set of insulated boot liners available. For serious winter use plastic winter mountaineering boots are strongly recommended. The vast majority of winter foot wear is designed for fashion, car driving and walking across a plowed parking lot from the car to the mall, they have absolutely no place in outdoor recreation and work. Heavy work shoes and steel toe safety shoes are not comfortable for extensive walking and load carrying and are not well insulated. Footwear, like eveything from food to vehicles, is made for specific purposes. Get the one that is suitable for the purpose.

Miscellaneous comments.

Outdoors in the eastern United States you will always have to deal with moisture. Rain, high humidity, perspiration, wet ground cover, puddles, swamps and unexpected weather changes all require proper clothing.

All clothing works better when clean. Dirt holds moisture and inhibits wicking. Dirt and wood smoke plug the microscopic vapor permeable feature in "waterproof-breathable" fabrics.

These "water proof-breathable" fabrics may not be so wind and waterproof in strong wind driven rain or snow situations and directly under back pack straps.

About half of your body heat is lost through your neck and head, so give serious thought to the protection of this often overlooked portion of the body. Remember the old saying "If your feet are cold, put a hat on!". Or a scarf, hood, face mask, goggles, helmet...

Mittens are warmer than gloves. Glove liners worn under mittens is a good and versatile combination. Leather work gloves provide almost no insulating value.

Read clothing tags. Know what the fancy name materials are actually made from. Avoid cotton and cotton blends. COTTON KILLS!!! These basic outerwear comments apply to all outer wear including jackets, pants, hats, mittens and sleeping bags.

Consider always wearing a helmet, a minor slip and fall can be fatal in the great outdoors.

Good sunglasses with side shields are a must on snow and at higher altitudes. Inexpensive safety goggles will provide eye protection from small tree branches when in the woods at night.

Carry large plastic trash bags for additional wind and rain proofing and survival needs.

Carry plenty of sweetened drinking water to keep your heating system and data processing unit properly hydrated and fueled for effective operation of these two life-critical components of your overall system.

Wind proof matches should be carried for starting additional emergency warmth.

Carry a whistle to attract attention. All of this information applies year round.

Enjoyment and productivity are directly related to comfort!!!