Risk of cold stress

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. What constitutes cold stress and its effects can
vary across different areas of the country. In regions relatively unaccustomed
to winter weather, near freezing temperatures are considered factors for "cold
stress." Whenever temperatures drop decidedly below normal and as wind speed
increases, heat can more rapidly leave your body. These weather-related
conditions may lead to serious health problems.

More information - Source: Centre for Occupational Health and Safety