Sourced from OSHA
Cold stress drives down the skin temperature and, eventually, the internal body temperature (core temperature). In a cold environment, most of the body's energy is used to keep the internal core temperature warm. Over time, the body will begin to shift blood flow from the extremities (hands, feet, arms, and legs) and outer skin to the core (chest and abdomen). This shift allows the exposed skin and the extremities to cool rapidly and increases the risk of frostbite and hypothermia.
HOW COLD IS TOO COLD?
What constitutes extreme cold and its effects can vary across different regions. In areas that are not used to winter weather, near-freezing temperatures are considered "extreme cold." A cold environment forces the body to work harder to maintain its temperature. Heat can leave your body more rapidly when temperatures drop below normal and wind speed increases.
Wind chill is the temperature your body feels when air temperature and wind speed combine. For example, when the air temperature is 40°F and the wind speed is 35 mph, the effect on the exposed skin is as if the air temperature was 28°F.
WHAT ARE THE RISK FACTORS THAT CONTRIBUTE TO COLD STRESS?
Some of the risk factors that contribute to cold stress are:
- Dressing improperly
- Predisposing health conditions such as hypertension, hypothyroidism, and diabetes
- Poor physical conditioning
WHAT ARE THE MOST COMMON COLD-INDUCED ILLNESSES/INJURIES?
- Hypothermia – Hypothermia occurs when body heat is lost faster than it can be replaced, and the normal body temperature (98.6°F) drops to less than 95°F. Hypothermia is most likely at frigid temperatures, but it can occur even at cool temperatures (above 40°F) if a person becomes chilled from rain, sweat, or submersion in cold water.
- Frostbite – Frostbite is a bodily injury caused by freezing the skin and underlying tissues. The lower the temperature, the more quickly frostbite will occur. Frostbite typically affects the extremities, particularly the feet and hands.
- Trench Foot – Trench Foot or immersion foot is caused by prolonged exposure to wet and cold temperatures. It can occur at temperatures as high as 60°F if the feet are constantly wet.
HOW CAN COLD STRESS BE PREVENTED?
Although OSHA does not have a specific standard covering working in cold environments, employers should train workers to prevent and recognize cold stress illnesses and injuries and how to apply first aid treatment. Workers should be trained on the appropriate engineering controls, personal protective equipment, and work practices to reduce the risk of cold stress.
Dressing appropriately during cold months is extremely important in preventing cold stress. The type of fabric worn also makes a difference. Cotton loses its insulation value when it becomes wet. On the other hand, wool, silk, and most synthetics retain their insulation even when wet.
The following are recommendations for working in cold environments:
- Wear at least three layers of loose-fitting clothing: An inner layer of wool, silk, or synthetic to keep moisture away from the body, A middle layer of wool or synthetic to provide insulation even when wet, and an outer wind and rain protection layer that allows some ventilation to prevent overheating.
- Wear a hat or hood to help keep your whole body warmer.
- Wear insulated and waterproof boots (or other footwear).
- Use insulated gloves to protect the hands (water resistant if necessary).
- Use a knit mask to cover the face and mouth (if needed).
SAFETY TIPS FOR WORKERS
- Your employer should ensure that you know the symptoms of cold stress.
- Monitor your physical condition and that of your coworkers.
- Dress appropriately for the cold.
- Stay dry in the cold because moisture or dampness, such as from sweating, can increase the body's heat loss rate.
- Keep extra clothing (including underwear) handy if you get wet and need to change.
- Drink warm sweetened fluids (no alcohol).
- Use proper engineering controls, safe work practices, and personal protective equipment (PPE) provided by your employer.
Anyone working in a cold environment may be at risk of cold stress, especially those required to work outdoors for extended periods. Make sure you and your crew are protected against the elements this winter.
ABATIX offers a wide selection of cold stress prevention products. You can always rely on our team of knowledgeable reps to help you make the most informed decisions. Contact your local ABATIX rep today.