Clothing is an important asset and is the most immediate form of protection. Clothing is important in staying alive, especially if food, water, shelter, and fire are limited or unobtainable. This is especially true in the first stages of an emergency situation because you must work to satisfy other needs. If you are not properly clothed, they may not survive long enough to build a shelter or fire, to find food, or to be rescued.
The need for adequate clothing and its proper care and use cannot be overemphasized. The human body’s tolerance for temperature extremes is very limited with clothing being the first line of defense. However, its ability to regulate heating and cooling is extraordinary. The availability of clothing and its proper use is extremely important to regulate temperature. Clothing also provides excellent protection against the external effects of alpha and beta radiation, and may serve as a shield against the external effects of some chemical or biological agents.
- • Clean. Dirt and other materials inside fabrics will cause the insulation to be ineffective, wear away and cut the fibers which make up the fabric, and cause holes. Washing clothing in the field may be impractical; therefore, you should concentrate on using proper techniques to prevent soiling clothing. This should include avoiding, if possible, kneeling in dirt or wiping dirty hands or equipment on clothing.
- • Overheating. Clothing best serves the purpose of preserving body heat when worn in layers as follows: absorbent material next to the body, insulating layers, and outer garments to protect against wind and rain. Because of the rapid change in temperature, wind, and physical exertion, garments should allow donning and removal quickly and easily. Ventilation is essential when working because enclosing the body in an airtight layer system results in perspiration which wets clothing, thus reducing its insulating qualities.
- • Loose. Garments should be loose fitting to avoid reducing blood circulation and restricting body movement. Additionally, the garment should extend beyond the waist, wrists, ankles, and neck to reduce body heat loss.
- • Dry. A small amount of moisture in the insulation fibers will cause heat losses up to 25 times faster than dry clothing. Internally produced moisture is as damaging as is externally dampened clothing. The outer layer should protect the inner layers from moisture as well as from abrasion of fibers.
- For example, wool rubbing on logs or rocks, etc. The outer shell keeps dirt and other contaminants out of the clothing. Clothing can be dried in many ways. Fires are often used however; take care to avoid burning the items. The “bare hand” test is very effective. Place one hand near the fire in the approximate place the wet items will be and count to three slowly. If this can be done without feeling excessive heat, it should be safe to dry items there. Never leave any item unattended while it is drying.
- Leather boots, gloves, and mitten shells require extreme care to prevent shrinkage, stiffening, and cracking. The best does not escape the boot), or simply walk them dry in the milder climates. The Sun and wind can be used to dry clothing with little supervision other than checking occasionally on the incoming weather and making sure the article is secure. Freeze-drying is used in subzero temperatures with great success. Let water freeze on or inside the item and then shake, bend, or beat it to cause the ice particles to fall free from the material. Tightly woven materials work better with this method than do open fibers.
- • Examine. All clothing items should be inspected regularly for signs of damage or soil.
- • Repair. When damage is detected, immediately repair it.
People have worn clothing for protection since they first put on animal skins, feathers, and other coverings. In most parts of the world, people need clothing for protection from harsh climates. Clothing also provides protection from physical injuries caused by vegetation, terrain features, environmental extremes, and animal life which may cause bites, stings, and cuts.
Clothing is made from a variety of natural and synthetic materials such as nylon, wool, and cotton. The type of material used has a significant effect on protection. When two or three layers of material are worn, a layer of air is trapped between each layer of material creating another layer of dead-air or insulation. The ability of these different fibers to hold dead-air is responsible for differing insulation values. Potential you must be aware of both the environmental conditions and the effectiveness of these different materials in order to select the best type of clothing for a particular geographic region.
Natural materials include fur, leather, and cloth made from plant and animal fibers such as wool and cotton.
• Fur and leather are made into some of the warmest and most durable clothing. Fur is used mainly for coats and coat linings. Animal skin has to be treated to make it soft and flexible and to prevent it from rotting.
• Although wool is somewhat absorbent, it retains most of its insulating qualities when wet. It contains natural lanolin oils which helps garments shed water increasing its thermal qualities.
• Cotton is a common plant fiber widely used to manufacture clothing. It absorbs moisture quickly and, with heat radiated from the body, will allow the moisture to pass away from the body. It does not offer much insulation when wet. It can be used as an inner layer against the skin with insulation (for example, wool, Dacron pile, synthetic batting) sandwiched between. The cotton protects the insulation and, therefore, provides warmth.
Many synthetic materials are stronger, more shrink-resistant, and less expensive than natural materials. Synthetic fibers are manufactured from chemicals derived from water, coal, and petroleum. The fibers are of different lengths, diameters, and strengths, and sometimes have hollow cores. These fibers, woven into materials such as nylon, Dacron, polypropylene and batting type material with air space between the fibers, providing excellent insulation when used inside clothing.
Down is the soft plumage found between the skin and the contour feathers of birds. Ducks and geese are good sources for down. If used as insulation in clothing, remember that down will absorb moisture (either precipitation or perspiration) quite readily. Because of the light weight and compressibility of down, it has wide application in cold-weather clothing and equipment. It is one of the warmest natural materials available when kept clean and dry. It provides excellent protection in cold environments; however, if the down gets wet it tends to get lumpy and loses its insulating value.
Double Socks are made by inserting cushion padding, feathers, dry grass, or fur between the layers of socks, and the wrapping parachute or other fabric around the feet, and tying above the ankles
Keep Head and Ears Covered
At 50°F, as much as 50 percent of total body heat can be lost from an unprotected head.
Using the Hood to Funnel Radiant Heat
The hood is designed to funnel the radiant heat rising from the rest of the body and to recycle it to keep the neck, head, and face warm (Figure 12-5). The individual’s ability to tolerate cold should dictate the size of the front opening of the hood. The “tunnel” of a parka hood is usually lined with fur of some kind to act as a protecting device for the face. This same fur also helps to protect the hood from the moisture expelled during breathing. The closed tunnel holds heat close to the face longer; the open one allows the heat to escape more freely. As the frost settles on the hair of the fur, it should be shaken from time to time to keep it free of ice buildup.
Sleeping systems (sleeping bag, liner, and bed) are the transition “clothing” used between normal daytime activities and sleep.
Extra Insulation for Sleeping Bags
The insulating material in the sleeping bag may be synthetic or it may be down and feathers. Note that, while the covering is nylon, feathers and down lining require extra protection from moisture. Sleeping bags are compressed when packed and must be fluffed before use to restore insulation value. Clean and dry socks, mittens, and other clothing can be used to provide additional insulation.