Hypothermia & Snowmobilers

Hypothermia is a Serious Threat to Snowmobilers

Hypothermia is the condition where your body loses more heat than it can produce. The four main causes of heat loss are:


Radiation- bare skin radiates heat to the open air. Always wear a warm hat since you can lose up to 80% of your heat through an uncovered head.


Convection- is where body heat warms the surrounding air and is then taken away by the wind. The stronger the wind, the faster the heat loss.


Conduction- when we touch cold objects heat is transferred rapidly to that object. Avoid sitting or lying on snow, ice, rocks or cold ground.


Evaporation- when we get wet, moisture evaporates like a swamp cooler. Wet skin and clothes lose heat many, many times faster than when we are dry.


The 5 stages of hypothermia are as follows:


STAGE 1 occurs at a body temperature from 98.6 to 96 degrees F. You will notice severe shivering as your body exercises the muscles to produce heat.


STAGE 2 comes when the body temperature falls to 95 to 91 F. Shivering becomes violent, speech becomes difficult, thinking is slow and sluggish and sometimes amnesia may occur.


STAGE 3 happens when body temperature drops to 90 to 86 F. Shivering will stop; this is a very important sign! Muscles may become rigid and skin will become blue and puffy. Other symptoms are poor physical coordination, unclear and muddled thinking, and muscle spasms that appear as jerking. The victim is still usually able to stand or sit at this stage, though.


STAGE 4 involves a body temperature of 86 to 78 F. At this point the victim becomes unconscious and reflexes are depressed.


STAGE 5 is anything less than 78 F. This stage is fatal, as the victim will go into cardiac arrest. The best way to avoid hypothermia is to dress in warm layers, with waterproof and windproof outer clothing, stay dry, find shelter from the wind and build a fire. Don’t let hypothermia set in before you begin to seek shelter. When someone in your group starts to feel the cold, stop and warm them before continuing.


If hypothermia does occur, warm the core of the person first. Do not start by warming the hands and feet as this can send cold blood back to the victims’ heart and cause cardiac arrest even though the victim may only be in the second or third stage of hypothermia. Warm the head, neck, and torso first. Hot liquids laced with sugar are an excellent way to warm a person, as the sugar is absorbed rapidly into the blood stream. High-energy foods will also help the body begin metabolizing and providing its own heat. Remove wet clothing and replace it with dry clothes. If a sleeping bag is available, place the hypothermic person in it with a non-hypothermic person for body-to-body warmth. DO NOT give alcohol to a person suffering from cold or hypothermia. This opens blood vessels at the surface of the skin, allowing heat to be lost more rapidly.