In Washington State, the average summer water temperature is just 55 degrees. This may not sound that cold, but it can be deadly. Warm air temperatures can create a false sense of security for fishermen, boaters, and recreational swimmers.
When a human body enters cold water, it goes into shock. This “cold shock” can cause dramatic changes in blood pressure, heart rate, and breathing. Cold water drains heat from the body up to 4 times faster than cold air. Immersion in cold water without a lifejacket or immersion suit can be life-threatening for even the most experienced swimmers.
Cold shock is the physiological reaction that takes place when a person enters cold water. The sudden lowering of skin temperature produces involuntary responses almost immediately. Over breathing or involuntary gasping can cause dizziness and inhalation of water. Blood vessels near the surface of the skin will constrict, reducing circulation. Blood pressure rises as the heart pumps against these constricted blood vessels. The risk of heart attack or stroke increases.
Physical incapacitation results in the loss of muscular control which affects the legs, arms, hands, and feet. With the loss of muscular control, keeping afloat without a lifejacket or flotation device becomes impossible. As the body weakens, this progressive loss of control can lead to drowning in even the most accomplished swimmer.
Genuine hypothermia becomes a reality after about 30 minutes. Uncontrollable shivering will stop as the body continues to cool. Without rescue this may ultimately lead to unconsciousness and loss of life.
If you find yourself in a cold water emergency, the U.S. Coast Guard recommends the following:
• Stay calm.
• If you are able, get out of the water ASAP, using floating objects if possible. In the meantime, keep as much of your body out of the water as possible.
• Evaluate your options. If you can swim to safety, stay calm and do so. If you can’t, conserve energy and heat and await rescue.
• The “Heat Escape Lessening Position” (HELP) slows down the loss of heat from your body in water. Draw your knees to your chin and keep your legs together, and press both arms against your side, keeping your head out of the water. If in a group, huddle to conserve heat.
If you are helping someone who is suffering from cold water exposure, it is recommended that you:
• Call 911.
• Gently move the person somewhere warm.
• Monitor their breathing and circulation and give CPR if needed.
• Remove wet clothing and dry the person off.
• Warm them slowly by wrapping blankets around them or putting on dry clothing. You can also use hot water bottles or chemical hot packs; just wrap them in a towel or blanket first.
• DO NOT warm them too quickly or immerse them in warm water, which could increase the risk of heart arrhythmia.
• Warm the core first, not the extremities. Warming hands and feet first can cause shock.
“You need to make sure when you’re going out on the water, you’re dressing for the water temperature not the air temperature. That you are prepared that in the event you do enter the water, you can survive,” said Ryan Koroknay, a recreational boating safety coordinator.
Whether you are working in the maritime trades or recreating, please plan accordingly, wear your life jacket, and stay safe.