By By the CCOHS
By By the CCOHS
Every winter, parts of Canada are plunged into freezing temperatures and frigid cold. This is bad news for outdoor workers for whom working in the cold can not only be hazardous to their health but also life threatening. The good news is that there are steps you can take to stay warm and safe, and take the chill out of working outside in the cold.
There are three challenges that must be addressed to enable workers to be safe in the cold: air temperature, air movement (wind speed), and humidity (wetness). Aside from several layers of protective, dry, clothing, and a healthy mix of physical activity, regular warm-up periods can help you work safely in, and defend yourself from the cold.
Effects of cold stress
Hypothermia (low body temperature) is the most common cold injury. Prolonged exposure to the cold causes the body to lose energy faster than it is produced, dropping body temperature. Warning signs are shivering, cold, pale, and dry skin; tiredness, confusion, and irrational behaviour; slow and shallow breathing; and slow and weakening pulse.
If you suspect hypothermia, immediately call for emergency assistance (911) and follow their instructions.
Frostbite is the second most common cold injury. Noses, ears, cheeks, fingers and toes are most often affected. The freezing constricts blood vessels, which impair blood flow and may cause permanent tissue damage. If only the skin and underlying tissues are damaged, recovery may be complete. However, if blood vessels are affected, the damage is permanent and could result in the amputation of the affected part.
Educate and inform workers and supervisors about symptoms of exposure to cold, proper clothing habits, safe work practices, physical fitness requirements for work in cold, and emergency procedures. Clearly outline procedures for providing first aid and obtaining medical care and assign at least one trained worker per shift the responsibility of attending to emergencies.
Make heated warming shelters such as tents, cabins or rest rooms available for those who work continuously in sub-zero temperatures. Pace the work such that workers won’t sweat excessively. If such work is necessary, provide proper rest periods in a warm area and allow employees to change into dry clothes. Give new employees enough time to get acclimatized to cold and protective clothing before assuming a full workload.
What to wear – top to bottom
To stay safe and dry, insulate yourself against cold temperatures, wind, and humidity with clothing appropriate for the type of work you will be doing and in the conditions you will be performing it. Wear several layers of loose clothing so you can regulate your comfort; remove a layer before you get too warm and start sweating, or add a layer if you are too cold. Under extremely cold conditions, heated protective clothing should be made available.
When you are using face protection in extremely cold conditions, make sure your eye protection is separated from your nose and mouth to prevent eye shields or glasses from fogging and frosting. Wear a wool knit cap or a liner under a hard hat to prevent heat loss.
If fine manual dexterity is not required, gloves should be used below four degrees Celsius for light work and below minus seven degrees Celsius for moderate work. For work below minus 17 degrees Celsius, mittens should be used.
Wear socks that will stay dry and that are the right thickness for your boots – not so thick that they make your boots tight and squeeze your foot – and not so thin that they make your boots loose and cause blisters. Have extra socks so you can dry your feet and change socks during the day.
Keep your feet warm in felt-lined, rubber bottomed, leather-topped boots that breathe and let perspiration evaporate. However, if work involves standing in water or slush, be sure to wear waterproof boots. While they protect the feet from getting wet from cold water, they also prevent the perspiration from escaping. Socks will become wet more quickly and increase the risk for frostbite.
Other prevention tips
- Avoid using alcohol, nicotine or other drugs that may affect blood flow and cause the body to lose heat and thus increase the risk of hypothermia.
- Don’t expose yourself to cold temperatures after a recent shower or bath.
- Keep moving; avoid sitting or standing still for long periods of time.
- Take regular breaks from the cold in warm places.
- Eat properly and frequently to maintain body heat and prevent dehydration.
- Drink fluids (hot non-alcoholic beverages or soup) often. especially when doing strenuous work to keep warm and hydrated. Limit the amount of caffeinated drinks as they can dehydrate you and cause you to lose body heat.
Wind chill hazards
0 to -9 degrees Celsius
- Low risk
- Dress warm and stay dry
-10 to -27 degrees Celsius
- Moderate risk
- Dress in layers with outer layer that is wind-resistant; stay dry and keep active
-28 to -29 degrees Celsius
- High risk
- Dress in layers; cover exposed skin with scarf or face mask; stay dry and keep active
-40 to -47 degrees Celsius
- Very high risk
- Dress in layers; cover all exposed skin; stay dry and keep active
-48 to -54 degrees Celsius
- Severe risk
- Dress in layers; cover all exposed skin; stay dry and keep active; be ready to cancel or cut short all outdoor activities.
The Canadian Centre for Occupational Health and Safety (CCOHS) promotes the total well being of workers in Canada by providing information, training, education, systems and solutions that support health and safety programs and injury and illness prevention. www.ccohs.ca