HYPOTHERMIA—What It Is and How to Avoid It

There are many things to consider once the winter season arrives and cold temperatures ensue. If you enjoy the outdoors and live near a pond or lake, you may encounter a frozen creek that you must cross.

During the winter months, being cold can be more than uncomfortable—it can be a health risk, especially if the exposure lasts for a lengthy period of time. It is even more dangerous to be cold and wet, such as if you were to cross a frozen creek, break through ice, and fall into the water. It is important to plan for the unexpected, because hypothermia—an abnormally low body temperature (below 95 degrees Fahrenheit)—can occur when a person is exposed to extremely cold temperatures.

Hypothermia can even occur at cool temperatures (above 40 degrees Fahrenheit) from submersion in cold water, rain, or sweat. The human body begins to lose heat faster than it is produced when it is exposed to very cold temperatures—causing a lower body temperature due to the body’s stored energy being used up. Unfortunately, victims of hypothermia may not be able to move well or think clearly because the brain is affected when body temperature is too low. This is a dangerous situation because a person may not know what is happening and will not be able to do anything about it.

Although it may be tempting to walk or skate across a frozen lake or pond, it is a good idea to check with local experts and resources to obtain knowledge about the surrounding ice conditions first (e.g., a news telecast, residents, or staff at a local bait shop or resort). This type of information may be helpful in determining the safest way to approach and handle ice and in preventing hypothermia. Similarly, knowing the key characteristics of ice can be helpful. For example, old ice is not as strong as new ice; it is difficult for ice to form when there are underwater currents; when ice creates a cracking or booming noise it does not always mean the ice is unsafe, it can mean that temperature changes are causing the ice to shift; and bodies of water do not freeze uniformly.

Whether it is safe to walk or skate on ice can often be determined by the thickness of the ice. Be sure to check ice thickness every 150 feet. Ice thickness guidelines include:

• When ice is 2 inches thick or less, DO NOT GET ON THE ICE.
• When ice is 4 inches thick, activities on foot, such as ice fishing, are generally safe.
• When ice is 5 inches thick, it is generally safe for ATVs or snowmobiles.
• When ice is between 8 and 12 inches thick, it can generally support a car or small pickup truck.
• When ice is between 12 inches and 15 inches thick, it can generally support a midsize truck.

Ice thickness is not the only characteristic of ice to consider for safety; color is also important. Clear ice is typically newer and the strongest; air pockets in white to opaque colored ice make it weaker than clear ice; and light gray to dark black ice is unsafe and should be avoided as they generally do not hold heavy, weighted loads. Moreover, slushy ice should be avoided because, though the top may look non-threatening, its bottom layer, often referred to as “rotten†ice due to its texture, will unlikely be able to sustain weighted objects.

Warning signs of hypothermia include shivering, confusion, loss of memory, slurred speech, drowsiness, fumbling hands, and feeling very tired or exhausted.

If you ever fall through ice that is thin, there are several survival tips to keep in mind. It is important to stay calm; flailing your arms misspends energy and valuable body heat. Since hypothermia will set in after approximately 10 minutes in the icy water, try to get in a horizontal floating position and slide horizontally onto the ice by kicking as hard as you can.

As a reaction to the extremely cold water, the body naturally reacts by gasping for air which can lead to hyperventilation, which can cause lightheadedness and even lead to loss of consciousness. Any person nearby should immediately call for help, and avoid falling in as well by staying away from the broken portion of the ice. Help can be offered by throwing something a person can grab onto, such as a rope or a branch, to be pulled out of the water.

Although it is instinctive to stand up once you get out of the water, it is better to roll over the ice until you are safe. There’s a greater likelihood of falling back into the water if you stand up.

Additionally, hypothermia can still occur once you are out of the freezing water. You should find shelter in a car or a building; remove any wet clothing; have something warm to drink; and if possible, keep your blood flowing by continuing to move your body. Continue to keep yourself dry and warm by wrapping your body, including your neck and head, in a warm blanket. Seek medical attention as soon as possible.

Warning signs of hypothermia include shivering, confusion, loss of memory, slurred speech, drowsiness, fumbling hands, and feeling very tired or exhausted. Even if a person with severe hypothermia may not seem to be breathing or have a pulse, handle the person gently to perform cardiopulmonary resuscitation, or CPR. Seek emergency assistance immediately; sometimes hypothermia victims who seem to have died can be resuscitated successfully.

It is important to keep this information and safety tips in mind when venturing out to enjoy the winter season. You can potentially avoid disaster and hypothermia by being aware of how to stay safe in the cold weather and on the ice.