by Scott Meaker

LOSS OF BODY HEAT is caused in four main ways:

1. RADIATION - Non-insulated bodies lose heat when the temperature is colder that 50 degrees

2. CONDUCTION - Contact between our body and a cooler substance such as water (rain, sweat) snow, the ground.

3. CONVECTION - Moving air or water removes warmth at very accelerated rates. Wind chill or submersion in lake or stream.

4. EVAPORATION - Breathing and sweating. Fluids must be replenished.

HYPOTHERMIA PREVENTION

GENERAL PRECAUTIONS Do not allow cotton clothing. Plan on ample water and food consumption. Take steps to stay dry or to change clothes when activity stops and wet clothes start cooling the body. Pair up to watch each other for signs of early stages (see below) of hypothermia. Cover head and hands at all times. Have warming tents or vehicles near by if possible. Plan to stay dry from perspiration by wearing the proper clothing. People that do not have the proper clothing should not be allowed to venture into cold, wet or highly active conditions. Staying dry is the most important factor in keeping body heat.

RADIATION

Wear insulated clothing. Wear a good hat and gloves (even in bed). Hands and heads have lots of blood vessels and are a major source of heat loss. At 40 degrees, 50% of body heat loss is through the head and hands, raising to 75% at 5 degrees. Contact with snow, water or high winds will accelerate this rate.

Wet clothing is the main cause of body heat loss. Sweat is a major factor in wet clothing. AVOID COTTON CLOTHING at all costs. No cotton long johns, jeans or t-shirts should be worn. Water proof, non-breathable outer-wear can seal in body perspiration that will soak your inner clothing and cause cold, wet conditions against the skin. Use polypropylene or polyester long johns, wool, polar-fleece, and other synthetic, wicking fibers clothing. Change out of wet clothing as soon as you are able.

Wind and water (not sweat) must be kept from the body. Wear clothing that blocks the wind such as ski clothes or rain- wear. Wear insulated clothing under this protection. If your clothing is wet from perspiration and wind chill is a factor, this condition can be fatal. If submerged in water, get out as soon as possible, and change into dry clothes ASAP. Always store change of clothes in your pack in plastic zip-lock bags to keep them dry in the case your pack is soaked some how.

Breathing and sweating evaporates the fluids in your body. Fluids are the medium that your body uses to carry heat to the body parts. When you become dehydrated, your body can not continue to heat itself. Drink lots of fluids during the day, especially in cold weather, high altitudes, or during high exertion. Often one quart of water / hour is needed to maintain body heat. Food is the fuel that the body uses to heat the fluids, so adequate food consumption is important to keep the body engine working on creating heat. Carbohydrates burn quickly and create heat and energy on the short term and fats and proteins provide long term fuel.

EARLY STAGE - Blueish lips, lack of attentiveness and memory, becoming "rummy". Hands, feet feel cold.

Treat: Remove wet clothes, add warmer clothing, get out of cold,. Feed warm fluids or warm food.

INTERMEDIATE STAGE - Shivering, exhaustion, drowsiness. Arms, legs feel cold.

Treat: Remove wet clothing and get warm clothes or sleeping bag around the person. This person can not help himself normally and may require assistance. Give warm fluids and get out of cold if possible.

EMERGENCY STAGE - Shivering stops! Muscles become rigid and hard. Breathing and heart beat slows dramatically.

Treat: This is a medical emergency! This person can not help himself. Immediate warming of the body core is essential but must be done carefully and gradually so as to not create cardiac arrest. Remove wet clothes. Add insulated clothing or sleeping bag and have another person enter the bag with them. This person usually can not heat himself and requires the heat of another individual. Remove person to a heated area if possible. Feed warm fluids but not food. Get immediate medical attention

FATALITY STAGE - Unconsciousness occurs. Heartbeat and breathing may not be detectable. Even if the body is warmed up the body core temperature can not be raised in a wilderness situation. Clinical assistance is required to save this person.

For classes, presentations, or more info contact Scott at Beaver2som@aol.com - (206)937-3259