Keeping the Chill Out: Working Safe in Cold Weather

As the winter months approach, we must pay attention to anyone who might be working or playing in cold environments.

Working in a cold environment can involve several adverse effects on human performance and health. Workers suffering from exposure to the cold can experience thermal discomfort, increased strain, decreased performance and cold-related diseases and injuries. Cold also can modify or aggravate the risk of common hazards and increase the risk of cold-associated injuries.

A number of industries and occupations involve substantial outdoor cold exposure. These include construction workers, postal workers, delivery people, utility and telecommunication workers, firefighters, police and others. Many indoor workers — such as those in the food processing industry, cold storage industry, supermarkets or in the transportation chain — also can be negatively impacted by cold work environments if not properly protected and trained.

HEALTH EFFECTS OF COLD

Cold temperatures have hazardous effects on humans and their ability to work well. When the body is exposed to cold temperatures, the negative effects can include dehydration, numbness, shivering, frostbite, immersion foot and hypothermia.

These negative effects are experienced first by the peripheral parts of the body and gradually progress to deep body tissues and the body core. When the body's core temperature drops below 95 F/35 C, it is defined as hypothermia, which along with frostbite is one of the more extreme dangers of prolonged work in cold environments.

Frostbite is a severe reaction by the skin to cold that can permanently damage fingers, toes, the nose and the ear lobes. Frostbite actually freezes and crystallizes the fluids in the body tissues and cellular spaces. This can damage the blood vessels, causing blood clotting and lack of oxygen to the affected area and deeper tissues. In severe cases, frostbite can kill and damage tissue to the extent that an amputation may be required.

Factors that influence how severe frostbite can be include the length of time an employee is exposed to the cold, the temperature outside, the wind chill factor (force of the wind), the amount of humidity in the air, dampness of clothing, high altitudes and whether the person has ingested alcohol or other drugs.

Alcohol and drugs can impair thinking, which can cause more damage due to lack of common sense in caring for the affected area. It also can cause further constriction of blood vessels, which prevents warm blood from reaching affected areas, worsening the frostbite. Frostbite can occur in just a few minutes if conditions are cold enough with a high wind-chill factor on unprotected body parts, for example, the ears.

Some employees are at higher risk of frostbite. Those at risk include older employees, those with circulation problems, anyone with a previous history of frostbite, those who ingest alcohol, use nicotine or take beta-blocker medications. Employees who have had a recent injury or blood loss also are at a higher risk of frostbite. Employees who do not take precautionary measures, such as wearing the appropriate protective clothing to prevent frostbite, also are at high risk. Training for all employees in the dangers of cold temperatures is essential.

SYMPTOMS OF FROSTBITE

Mild frostbite (frostnip) affects the outer skin layer and appears as a blanching or whitening of the skin. These symptoms usually disappear as the affected area warms. The skin may appear red for several hours.

Superficial frostbite can result in blistering. The skin feels numb, waxy and frozen, and can look grayish-yellow, grayish-blue or white. Ice crystals form in the skin cells and the rest of the skin remains flexible.

Deep frostbite is the most serious of frostbite cases. Sensation usually is absent in the affected area and blistering usually does not occur. The blood vessels, muscles, tendons, nerves and bone may be frozen. This can lead to permanent damage, blood clots and gangrene, which ultimately can lead to amputation and even death if professional medical attention is not obtained as soon as possible.

Other symptoms that indicate frostbite include swelling, itching, burning and deep pain as the area is warmed.

It is normal to feel pain in the affected area as it is rewarmed. Treatment of frostbite is best performed by trained medical professionals. But if you cannot get to help right away, you can do some simple things to assist someone to warm up.