The best way to survive an accidental cold water immersion is to wear a life jacket. It will help keep the head above water in the event of an accidental immersion. It will also keep the victim afloat. If unable to rescue themselves, a life jacket can provide some thermal protection against the onset of hypothermia, and keep the swimmer afloat until help arrives.
Swimming ability in warm water has little relationship to the ability to swim in cold water. Mario Vittone, a former Coast Guard rescue swimmer states “It is impossible to die from hypothermia in cold water unless you are wearing an approved flotation device, because without flotation , you won’t live long enough to become hypothermic, you will most assuredly drown.”
When the temperature of water is below 50 F significant physiological responses occur, including the possibility of death, The causes of death may include cardiac arrest, deep body (core) cooling resulting in unconsciousness, and circulatory collapse, all of which could end in drowning. The effects of cold water immersion are predictable and well documented by what is known as the 1-10-1 Principle:
– 1 minute: Upon immersion in cold water, the body reacts with an involuntary gasp, followed by hyperventilation of up to 10 times regular breathing (if head is underwater during that initial deep gasp, a person can inhale enough water to drown). Avoid panicking– breathing will return to close to normal.
– 10 minutes: A person immersed in cold water will become incapacitated as limb muscles stop working and prevent swimming or self-rescue, so swimmer should attempt to rescue themselves, before incapacitation becomes a factor. If this is not possible, try to get as much of the body out of the water as possible to delay the onset of hypothermia.
– 1 hour: After about 60 minutes (depending on the water temperature), the body continues to cool. The resulting hypothermia can create a range of symptoms from confusion to unconsciousness, eventually leading to death.
When rescuing a cold water victim beware of post rescue collapse (up to several hours after) by assisting the victim to become dry and warm. Keep him or her still until medical treatment arrives.