Cold weatherCold can be a serious occupational hazard for many workers. Construction, oil and gas extraction, trucking, firefighting, police work, farming/ranching, fishing, logging and other outdoor jobs are examples of occupations where the potential for serious cold injury exists. Fatal exposures to cold have most commonly resulted from accidental exposures involving immersion in low-temperature water and failure to escape from low-air-temperature environments.Workers do not need to be exposed to below-zero temperatures to experience cold-related conditions such as hypothermia. Indoor workers in refrigerated rooms or unheated buildings can also be at risk.Frostbite and hypothermia are two conditions of particular concern. Cold stress exposure charts can help protect workers from the most severe effects of cold stress and cold injury. They describe cold working conditions most workers can handle repeatedly without adverse health effects.Some factors that can contribute to the risk of cold injury include temperature, wind speed, moisture (perspiration or working near water), exposure duration, type of clothing, work/rest schedule, type of work being performed, use of certain medications, degree of acclimatization (previous exposure to cold) and the worker’s age and physical state.Cold weather risksFrostbite of the skin happens when tissue freezes. Any exposed skin is subject to frostbite when temperatures fall below freezing. Frostbite can lead to scaring, permanent tissue damage, possible amputation and disability. Symptoms of frostbite vary according to severity. Mild cases may produce prickling or burning sensations. Severe frostbite can produce extreme pain or none at all if nerve tissues are affected.Hypothermia occurs when the core body temperature drops below a level that allows it to maintain normal metabolic function, often only one or two degrees. Initial symptoms include a sensation of cold, followed by pain. As exposure time increases, the pain sensation is reduced, and overall numbness develops. Additional symptoms may include muscle weakness, confusion, slurred speech and drowsiness. Hypothermia can rapidly progress to coma and death.Wind chill cooling rate is the heat loss from a body, often expressed in watts per square metre. This rate is a function of air temperature and wind velocity.Prevention measures include:wearing layered, dry and insulated protective clothing with windproof and waterproof shellstaking warm-up breaks in heated shelters (when the temperature is -7˚C or lower, these shelters should be available nearby)staying hydrated with warm, sweet drinkskeeping the body moving but limiting heavy work to avoid perspirationmonitoring and assessing further weather changes throughout the dayLegislationPart 4.12 in the Manitoba Workplace Safety and Health Regulation states that when a workplace or work process exposes workers to conditions that risk a worker’s safety and health because of cold (or heat), an employer must carry out procedures and control measures for preventing thermal stress while at work.As noted in The Workplace Safety and Health Act, Section 4.12 – Thermal Stress, an employer must carry out safe work procedures and control measures to ensure that (a) the threshold limit values for thermal stress established by the American Conference of Governmental Industrial Hygienists (ACGIH) in its publication, Threshold Limit Values for Chemical Substances and Physical Agents and Biological Indices, are followed, and (b) the worker is provided with information, instruction and training in the symptoms of thermal stress and the precautions to be taken to avoid injury from thermal stress.Manitoba’s Workplace Safety and Health Act and associated regulations are in place to protect the safety and health of workers in Manitoba. Below is a link to the regulation part associated with this safety topic.Part 4 General Workplace Requirements Manitoba Workplace Safety and Health Act and RegulationRelated linksHazards and exposures topic list
