by Tim Butler, Director of Safety & Compliance
Workers who are exposed to extreme cold or work in cold environments may be at risk of cold stress.
Extreme cold weather is a dangerous situation that can bring on health emergencies in susceptible
people, such as those without shelter, outdoor workers, and those who work in an area that is poorly
insulated or without heat. Whenever temperatures drop decidedly below normal and as wind speed
increases, heat can more rapidly leave your body. These weather-related conditions may lead to serious
TYPES OF ILLNESS
Hypothermia– When exposed to cold temperatures, your body begins to lose heat faster than it can be
produced. Prolonged exposure to cold will eventually use up your body’s stored energy. The result is
hypothermia, or abnormally low body temperature. A body temperature that is too low affects the
brain, making the victim unable to think clearly or move well. This makes hypothermia particularly
dangerous because a person may not know it is happening and will not be able to do anything about it.
Frostbite– Frostbite is an injury to the body that is caused by freezing. Frostbite causes a loss of feeling
and color in the affected areas. It most often affects the nose, ears, cheeks, chin, fingers, or toes.
Frostbite can permanently damage body tissues, and severe cases can lead to amputation. In extremely
cold temperatures, the risk of frostbite is increased in workers with reduced blood circulation and
among workers who are not dressed properly.
Trench Foot– Trench foot, also known as immersion foot, is an injury of the feet resulting from
prolonged exposure to wet and cold conditions. Trench foot can occur at temperatures as high as 60
degrees F if the feet are constantly wet. Injury occurs because wet feet lose heat 25-times faster than
dry feet. Therefore, to prevent heat loss, the body constricts blood vessels to shut down circulation in
the feet. Skin tissue begins to die because of lack of oxygen and nutrients and due to the buildup of toxic
Chilblains– Chilblains are caused by the repeated exposure of skin to temperatures just above freezing to
as high as 60 degrees F. The cold exposure causes damage to the capillary beds (groups of small blood
vessels) in the skin. This damage is permanent, and the redness and itching will return with additional
exposure. The redness and itching typically occurs on cheeks, ears, fingers, and toes.
Employees should avoid exposure to extremely cold temperatures when possible. When cold environments or temperatures cannot be avoided, follow these recommendations to protect yourselves from cold stress:
Wear appropriate clothing.
- Wear several layers of loose clothing. Layering provides better insulation.
- Tight clothing reduces blood circulation. Warm blood needs to be circulated to the
- When choosing clothing, be aware that some clothing may restrict movement resulting in a
Make sure to protect the ears, face, hands and feet in extremely cold weather.
- Boots should be waterproof and insulated.
- Wear a hat; it will keep your whole body warmer. (Hats reduce the amount of body heat
that escapes from your head.)
- Move into warm locations during work breaks; limit the amount of time outside on extremely cold days.
Carry cold weather gear, such as extra socks, gloves, hats, jacket, blankets, a change of clothes and a
thermos of hot liquid.
Include a thermometer and chemical hot packs in your first aid kit.
Avoid touching cold metal surfaces with bare skin.
Monitor your physical condition and that of your coworkers.