Your body can cool 25 times faster in water than in air, according to the Coast Guard, so hypothermia is a primary concern in any overboard situation.
Water freezes at 32 degrees Fahrenheit. In waters that cold, the average adult has less than 15 minutes before losing consciousness and a maximum survival time of about 45 minutes, according to the Coast Guard. If the water is between 33 and 40 degrees, you can stay in for up to 30 minutes before passing out and survival time can be up to 90 minutes.
As the water temperature increases, the risks decrease. But severe cold, even if it is not lethal, can still bring on a range of symptoms that can make it hard or even impossible for a victim to facilitate their own rescue. Among them are shivering, numbness, loss of muscle control, difficulty speaking and sluggish thinking.
Because no one can control water temperature, the best defense it to be prepared. That means wearing proper personal flotation with emergency lighting, which will keep you afloat and allow you to conserve energy. It also means knowing how to act. Don't swim unless you are certain you can reach your target, whether it is a boat, person or object. Swimming takes energy and lowers your body temperature. Instead, keep your face and head out of the water and either hug your knees to your chest or straighten your body fully with your chin up. If there are others in the water, huddle for warmth. If you can safely climb up on an object and get out of the water, do so.
Coast Guard documents also say a few words about attitude. "Keep a positive outlook," the documents say, "it will improve your chances of survival."
-Theodore J. SawchuckÂ
