Cold Water Immersion

Boaters should be prepared if they or someone else on board is unexpectedly immersed into cold water. Being prepared can help your inclination to panic and increase your ability to survive. 1-10-1 is an easy way to remember the first three phases of cold-water immersion and the approximate time each phase takes.

1-10-1: The 3 Phases of Cold Water Immersion

  1. Cold Water Shock - 1 minute
    • Cold Water Shock occurs when a person experiences sudden immersion into water 15°C or below. Cold water can paralyze your muscles making it very difficult to put on a Lifejacket of PFD in the water, so it is very important that you are wearing one the entire time you are boating.
    • During Cold Water Shock a person will gasp for breath and may experience muscle spasms and a rise in heart rate and blood pressure. The instant muscle spasms and gasp reflux occurs can cause a person to involuntary ingest water and drown. A rise in heart rate and blood pressure can result in a heart attack or stroke.
    • You should concentrate on avoiding panic and getting control of your breathing. Wearing a Lifejacket during this phase is critically important to keep you afloat and breathing.
  2. Cold Incapacitation - 10 minutes
    • Over the next 10 minutes you will lose the effective use of your fingers, arms and legs for any meaningful movement. Swim failure will occur within these critical minutes.
  3. Hypothermia - 1 hour
    • Even in ice water it could take approximately 1 hour before becoming unconscious due to hypothermia. You should learn techniques of how to delay hypothermia, self-rescue, and calling for help in order to increase your chances of survival. In hypothermia, your core body temperature drops below normal levels resulting in weakened muscular functions, reduced coordination and slowing mental functions.

Heat Escape Lessening Position

If you do find yourself alone and immersed in cold water, use the Heat Escape Lessening Position (H.E.L.P.) to reduce heat loss from your core body temperature and delay side effects of hypothermia.

H.E.L.P. is performed as follows:

  1. Cross your arms tightly against your chest.
  2. Draw your knees up and against your chest.
  3. Keep you head and face out of the water.

Be prepared for cold water immersion

Heat escape lessening position