For workers who perform their jobs outdoors during winter months, or who work in artificially cold environments such as refrigerated areas, cold temperatures can be a major risk factor for injury and illness. In some cases, cold-related hazards can even be fatal.
What is Cold Stress?
According to the CDC, cold stress refers to the environmental conditions in which the body loses heat at a faster rate than it can produce it. This can include cold temperatures, windchill, rain, and inadequate protection. Cold stress can result in cold strain, the body’s physiological response to limiting heat loss (i.e. shivering, vascular changes, and cognitive decline), and eventually to cold injuries and illnesses such as hypothermia and frostbite.Examples of Cold Injuries & Illnesses
Because cold-related injuries can be severe or even fatal, it is extremely important that workers exposed to cold understand the risks and how to stay safe. Some examples of cold-related injuries include:Hypothermia
Hypothermia occurs when core body temperatures falls below 96.8 °F, often as a result to prolonged exposure to cold weather or wet conditions. People with hypothermia may experience shivering, fatigue, and confusion or disorientation that can progress to slowed breathing, cardiac dysfunction, and loss of consciousness. In 2019, 1,800 people in the U.S. died from hypothermia, and 32% of the fatal cases were work-related. Workers in construction, transportation, and other outdoor occupations are most at risk. First Aid: If a worker experiences hypothermia, take the following steps:- Alert supervisors / request medical assistance.
- Move the person to a warm room and remove wet clothing; warm the center of their body first with an electric blanket or skin-to-skin contact.
- Warm beverages can help raise body temperature; do not give alcoholic beverages or any beverage if the person is unconscious.
- Once the person’s body temperature has increased, keep them warm with a blanket.
- Perform CPR if the person is unresponsive and has no pulse.
Frostbite
Frostbite is an injury caused by freezing, and most often affects the fingers, toes, nose, ears, and face. Frostbite can permanently damage tissue and skin and in the most severe cases may lead to amputation. Symptoms include:- Reduced blood flow to feet and hands
- Tingling, stinging, or numbness
- Blue, pale or waxy skin
- Remove person to a warm room as soon as possible.
- Avoid walking on frostbitten feet and avoid massaging or rubbing frostbitten area, as this can increase damage.
- Submerge affected area in warm (but not hot) water and keep it warm by using body heat.
- Do not warm affected areas with a fire, stove, or heat lamp, as numbness can lead to burn injuries.
Trench Foot
Also known as immersion foot, trench foot is a non-freezing injury caused by prolonged exposure to wet and cold conditions. It happens when the body constricts blood vessels to prevent heat loss, as wet feet lose heat roughly 25x faster than dry feet. This can cause circulation in the feet to shut down, which in turn results in tissue death. Unlike other cold injuries, trench foot can occur in temperatures as high as 60 °F if the feet remain wet. Trench foot can cause blisters, ulcers, bleeding under the skin, and numbness. Workers with trench foot should remove wet shoes and socks, keep their feet dry and avoid working on them, and seek medical treatment.Preventing Cold Stress
OSHA does not have a specific standard for cold weather, but employers have a responsibility to recognize the dangers associated with cold temperatures and take the necessary steps to protect their workers. For example, employers should:- Train workers to recognize cold stress conditions and the symptoms of cold injuries
- Provide PPE and train workers on how to select the proper clothing and equipment for cold, wet, and windy conditions
- Monitor employees performing work in cold environments
- Schedule frequent breaks in dry and warm areas
- Schedule work for the warmest part of the day
- Have employees work together or in pairs
- Use engineering controls such as heaters