Workers who are required to work outdoors in cold environments for an extended period of time may be at risk for cold stress. Weather extremes, such as high winds, cold temperatures, ice, snow, sleet and freezing rain, present potential hazards to workers. Specifically, cold stress can contribute to hypothermia, frostbite, and trench foot.
The Risks of Cold Stress
- Hypothermia occurs when your body heat is lost faster than it can be replaced and your normal body temperature drops to less than 95 degrees Fahrenheit. Symptoms include shivering, fatigue, dilated pupils, blue skin, and a slowed pulse and breathing. If you suspect someone has hypothermia:
- Call for emergency assistance as soon as possible.
- Move the person to a warm, dry area. Do not leave them alone.
- Remove any wet clothing and replace it with warm, dry clothing or wrap the person in blankets.
- Have the person drink warm, sweet drinks (sugar water or a sports drink) if they are alert.
- Have the person move his or her arms and legs to create muscle heat.
- Frostbite is an injury to the body that is caused by freezing of the skin and underlying tissues. Symptoms include reduced blood flow to the hands and feet, numbness, aching and waxy or blistered skin. If you suspect someone has frostbite:
- Move the person to a warm, dry area. Do not leave him or her alone.
- Remove any wet or tight clothing that may cut off blood flow to the affected area.
- DO NOT rub the affected skin, as this can cause damage to the skin and tissue.
- Gently place the affected area in warm water (105° F) to slowly warm the tissue. Do not pour warm water directly on the skin because it may warm the tissue too fast and cause damage. Warming the skin generally takes about 25 to 40 minutes.
- After the affected area has been warmed, it may become puffy and blister, accompanied by a burning sensation or numbness. When normal movement, feeling and skin color have returned, dry the affected area and keep it warm.
- If the affected area could get cold again, do not warm the skin. Should the skin be warmed and then become cold a second time, there could be severe tissue damage.
- Trench foot is caused by prolonged exposure to wet and cold temperatures. Symptoms include numbness, leg cramps, swelling, blisters and ulcers.
What Can Workers Do?
To protect yourself whenever you’re working outdoors in extreme cold, consider doing the following:
- Wear several layers of loose clothing to provide insulation.
- Make sure to protect your ears, face, hands and feet.
- Move into warm locations during work breaks.
- Limit the amount of time you spend outside.
- Include a thermometer and chemical hot packs in your first-aid kit.
- Avoid touching cold metal surfaces with your bare skin.
If you have any additional questions or concerns regarding cold stress safety at work, consult your supervisor.