Hypothermia is a condition that exists when the body’s temperature drops below ninety-five degrees. This can be caused by exposure to water or air. The loss of body heat results in loss of dexterity, loss of consciousness, and eventually loss of life. A few minutes in cold water makes it very difficult to swim, even to keep yourself afloat. In addition, a sudden, unexpected entry into cold water may cause a reflexive "gasp" allowing water to enter the lungs. Drowning can be almost instantaneous.
Your body can cool down 25 times faster in cold water than in air. If you examine the chart below you will see that survival time can be as short as 15 minutes. Water temperature, body size, amount of body fat, and movement in the water all play a part in cold water survival. Small people cool faster than large people and children cool faster than adults.
Hypothermia does not only occur in extremely cold water. It can, and does, occur even in the warmer waters of Florida and the Bahamas.
Hypothermia Chart |
||
If the Water Temp. (F) is: |
Exhaustion or Unconsciousness |
Expected Time of Survival is: |
| 32.0° | Under 15 min. |
Under 15 - 45 min. |
32.5° - 40° |
15 - 30 min. |
30 - 90 min |
40° - 50° |
30 - 60 min. |
1 - 3 hours |
50° - 60° |
1 - 2 hours |
1 - 6 hours |
60° - 70° |
2 - 7 hours |
2 - 40 hours |
70° - 80° |
3 - 12 hours |
3 - Indefinite |
Over 80° |
Indefinite |
Indefinite |
Hypothermia is progressive - the body passes through several stages before an individual lapses into an unconscious state. The extent of a person's hypothermia can be determined from the following:
1. Mild Hypothermia - the person feels cold, has violent shivering and slurred speech.
2. Medium Hypothermia - the person has a certain loss of muscle control, drowsiness, incoherence, stupor and exhaustion.
3. Severe Hypothermia - the person collapses and is unconscious and shows signs of respiratory distress and/or cardiac arrest probably leading to death.

