Cold-related Illnesses in Workers

Hypothermia

When exposed to cold temperatures, your body begins to lose heat faster than it is 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.

Hypothermia is dangerous because a person may not know it is happening or be able to do anything about it.

Symptoms

Symptoms of hypothermia can vary depending on how long you have been exposed to the cold temperatures.

Early symptoms

• Shivering
• Fatigue
• Loss of coordination
• Confusion and disorientation

Late symptoms

• No shivering
• Blue skin
• Dilated pupils
• Slowed pulse and breathing
• Loss of consciousness

First aid

Take the following steps to treat a worker with hypothermia:

• Alert the supervisor and request medical assistance.
• Move the victim into a warm room or shelter.
• Remove their wet clothing.
• Warm them with an electric blanket or skin-to-skin contact.
• Provide warm beverages. Only give beverages to a conscious person.
  • Do not give the victim alcoholic beverages.
• After they have warmed up, keep the victim dry under a blanket.
• If victim has no pulse, begin cardiopulmonary resuscitation (CPR).

Immersion hypothermia from cold water

Cold water immersion creates a condition known as immersion hypothermia. It develops much more quickly than standard hypothermia. Hypothermia can occur in any water temperature below 70°F. Survival times can be lengthened by:

• Wearing proper clothing (wool and synthetics and not cotton)
• Using a personal flotation device (PFD, life vest, dry suit)
• Having a way to signal rescuers (strobe lights, whistles, flares)
• Having a way to be retrieved from the water.

For information about cold water survival and cold-water rescue, visit:

• NIOSH Commercial Fishing Safety Topic Page
• Alaska Marine Safety Education Association
• Minnesota Sea Grant
• U.S. Search and Rescue Task Force

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.
• Workers who are not dressed properly.

Symptoms

Symptoms of frostbite include:

• Reduced blood flow to hands and feet (fingers or toes can freeze)
• Numbness
• Tingling or stinging
• Aching
• Bluish or pail, waxy skin

First aid

Workers suffering from frostbite should:

• Get into a warm room as soon as possible.
• Avoid walking on frostbitten feet or toes.
• Immerse the affected area in warm (not hot) water.
• Warm the affected area using body heat.
  • For example, an armpit can warm frostbitten fingers.
• Do not rub or massage the frostbitten area.
• Do not use a heating pad, heat lamp, stove, fireplace, or radiator.
  • Affected areas are numb and can be easily burned.

Trench Foot

Trench foot, or 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°F if the feet are constantly wet. Wet feet lose heat 25-times faster than dry feet.

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 products.

Symptoms

Symptoms of trench foot include:

• Reddening of the skin
• Numbness or tingling pain
• Leg cramps
• Swelling
• Blisters or ulcers
• Bleeding under the skin
• Gangrene (the foot may turn dark purple, blue, or gray)

First aid

Workers suffering from trench foot should:

• Remove shoes/boots and wet socks.
• Dry their feet.
• Avoid walking on feet, as this may cause tissue damage.

Chilblains

Chilblains are caused by the repeated exposure of skin to temperatures just above freezing to 60°F. The cold exposure damages 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.

Symptoms

Symptoms of chilblains include:

• Redness
• Itching
• Possible blistering
• Inflammation
• Possible ulceration in severe cases

First aid

Workers suffering from chilblains should:

• Avoid scratching.
• Slowly warm the skin.
• Use corticosteroid creams to relieve itching and swelling.
• Keep blisters and ulcers clean and covered.