| Table of Contents |
| 26.1 Introduction |
| 26.2 Cold Stress Hazards |
| 26.3 Cold Stress Controls |
| Related Documents |
| Working Safely in Cold Weather |
26.1 Introduction #
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.
Cold stress refers to environmental conditions (e.g., air temperature/humidity, windchill temperature, rain, and inadequate clothing for protection) in which body heat is lost to the environment at a rate that is faster than the body can produce heat. Consult the US Customary Windchill Chart, an integration of air temperature and wind velocity, to provide an estimate of the cooling power of the environment. (Note that persons riding in open vehicles may be subjected to dangerous wind chills even when the natural wind velocity is low).
Cold strain refers to the physiological responses (e.g., attempts to compensate for body heat loss through vascular changes, increased metabolic production of heat, and shivering) involved in preventing or limiting body heat loss. Cold stress may progress to cold injury and illness. Cold injuries may include hypothermia, frostbite, redness, swelling, and cracking of exposed skin. As the victim becomes colder, they may experience muscle rigidity, reduced blood pressure, cardiovascular effects and a decrease in respiratory rate. Cold strain may also involve psychological impact to body heat loss, such as cognitive decline, poor judgment , and clouded consciousness.
Reference Regulations: OSHA Cold Stress Guide
26.2 Cold Stress Hazards #
Control of cold stress situations should follow the procedures outlined in this plan. Implement the appropriate control measures for the specific work condition, from among the following possible control methods.
Hypothermia, frostbite, trench foot, redness, swelling, and cracking of exposed skin are all illnesses and injuries caused by cold stress.
Hypothermia occurs when the body’s temperature becomes abnormally low. A body temperature that is too low affects the brain, making it difficult to think clearly or move well, and can eventually lead to death.
Frostbite is an injury to the body caused by freezing tissues. It can cause permanent damage and in severe cases, lead to amputation.
Trench foot is an injury of the feet resulting from prolonged exposure to wet and cold conditions. The wet feet lose heat faster and the circulation begins to shutdown, resulting in the skin tissue beginning to die. Redness and swelling are caused by the repeated exposure of skin to temperatures just above freezing to as high as 60°F. The cold exposure causes damage to the groups of small blood vessels in the skin. This damage is permanent and the redness and itching will return with additional exposure.
26.3 Cold Stress Controls #
Administrative controls #
Employers should take the following steps to protect workers from cold stress:
- Schedule maintenance and repair jobs in cold areas for warmer months.
- Schedule cold jobs for the warmer part of the day.
- Reduce the physical demands of workers.
- Use relief workers or assign extra workers for long, demanding jobs.
- Provide warm liquids to workers.
- Provide warm areas for use during break periods.
- Monitor workers who are at risk of cold stress.
- Provide cold stress training that includes information about:
- Worker risk
- Prevention
- Symptoms
- The importance of monitoring yourself and coworkers for symptoms
- Treatment
- Personal protective equipment
PPE for Cold Stress #
Employees should wear several layers of loose clothing. Avoid wearing tight fitting clothing that reduces blood circulation or restricts movement. Make sure to protect the ears, face, hands and feet in extremely cold weather
Wearing insulative PPE when available can be protective in cold environments if the PPE remains dry. Some examples of cold protective PPE are insulated coveralls, boots, and gloves. Highly insulating PPE worn while performing heavy work will result in a warm microclimate which can induce sweating. Once the physical activity stops, the sweat begins to evaporate causing further cooling which can contribute to cold stress. This should be considered when selecting PPE.
Administrative controls #
Workers should avoid exposure to extremely cold temperatures when possible. When cold environments or temperatures cannot be avoided, workers should follow these recommendations to protect themselves from cold stress:
- 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.
