Cold Water Immersion or Wind Chill (Hypothermia)

When a person is exposed to very low temperatures, he or she may develop hypothermia. Hypothermia occurs when the person’s body temperature drops below normal. Immersion in cold water, exposure to cool air in water-soaked clothing, or prolonged exposure to low environmental temperatures are the usual causes of this condition. This is a major factor in fatalities in small open vessels. The best prevention is safe boating, plus adequate safety equipment aboard.

In the early stage of hypothermia, affected persons: may shiver and have slurred speech; they are conscious but withdrawn.

In the intermediate stage, affected persons often: have a slow and weak pulse, slow respiration, and a lack of co-ordination. They display sleepiness and their behavior tends to be irrational or confused.

In the final stage, affected persons: display a weak, irregular or absent pulse, weak or absent respiration and possible unconsciousness.

The mental and muscle functions of the person affected will change as hypothermia progresses. You will need to watch for these changes and to take appropriate action. If a person is found to be suffering from hypothermia, remove the person from the source of cold exposure and, if possible, provide dry shelter. Prevent further decreases in body temperature by gradually warming the person’s body. Replace wet clothing with dry clothing. If possible, wrap the person in blankets, and place dry coverings over him/her. Cover the head and neck, and/or cover the body with an insulating device and vapor barrier. During that time concentrate on avoiding panic and getting control of their breathing. If the person affected asks for something to drink, you can offer warm liquids. Do not give alcohol or hot stimulants to the person. Do not rub or massage the surface of the person’s body or extremities. If necessary use or exhibit signals to indicate distress and/or the need of assistance.