149 people in Canada die every year due to cold water immersion, according to Transport Canada. In water colder than 5 degrees Celsius, you can lose consciousness in 20 minutes. Falling into icy water can lead to hypothermia and death in less than 2 minutes. Even warmer water can cool the body's temperature to the point you cannot function, so you fast action is needed. Cold air can cause hypothermia too.
Ted Rankine, Director of the Canadian Safe Boating Council says "Far too many people die within swimming distance of safety, such as a boat, dock or the shore, because of the initial effects of cold water immersion." Suddenly falling in cold water can cause shock, involuntary gasping and hyperventilation, followed by loss of movement and the inability to get out or swim.
The best way to survive a fall into cold water is by following the 1-10-1 rule accepted by search and rescue professionals.
People should use the first minute to regain control of breathing before trying their best to escape the water during the next 10 minutes. After that time, energy will be drained significantly.
The body generally has about one hour before the heart stops, although chances of survival vary according to other factors, such as fitness and body fat levels. Anything that impairs the ability to think clearly increases the risk of drowning. [Vancouver Sun]
It's possible to save someone in an advanced state of cold from exposure to air or water. It's estimated that as many as 25% of hypothermia deaths are due to rough handling during rescue.
Many thanks to the information in "Today's Boating" magazine (Fall 96) and government pamphlets on hypothermia.
Your body cools down many times faster in cold water than in air, causing death in as short as 15 minutes. Your size, body fat and movement play a part. This chart indicates how long you can expect to survive.
|Water temp. (F)||Celsius (C)||Exhaustion or
|32 F||0 C||Less than 15 minutes||15-45 minutes|
|32-40 F||0-5 C||15-30 minutes||30-90 minutes|
|40-50 F||5-10 C||30-60||1-3 hrs.|
|50-60 F||10-16 C||1-2 hours||1-6 hours|
|60-70 F||16-21 C||2-7 hours||2-40 hours|
|70-80 F||21-27 C||3-12 hours||3 hours up|
|More than 80 F||More than 27 C||Indefinitely||Indefinitely|