- January 6, 2026
- Kevin Kholer
Cold Stress in Canadian Workplaces: What Employers Need to Know This Winter
The Issue
As we approach the first day of winter in the Northern Hemisphere, workers across Canada face increased exposure to cold, wet, windy, and rapidly changing weather conditions. A cold environment challenges workers through:
- Air temperature
- Air movement (wind speed)
- Humidity and wetness
To stay safe, these challenges must be managed through appropriate clothing, controlled exposure, engineering controls, and proper work-rest cycles. The human body performs best when the core temperature remains around 37°C. Although sweating, shivering, and changes in blood flow help regulate temperature, the body can only adapt so far. Beyond certain environmental limits, its ability to maintain core temperature fails—and cold stress becomes a life-threatening hazard.
Context: Cold Exposure in Canadian Work Environments
Canada’s climate creates unique risks for outdoor and partially sheltered work. Extreme cold warnings, sudden temperature drops, blowing snow, freezing rain, and severe wind chills are common across provinces and territories from late fall through early spring.
Workers at highest risk include those in:
- Municipal operations and public works
- Construction and infrastructure projects
- Electrical utilities and power distribution
- Oil and gas extraction
- Transportation, trucking, and delivery
- Mining and natural resources
- Fisheries, marine operations, and logging
- Policing, paramedic, and emergency response
- Agriculture and farm operations
Cold stress can occur even at temperatures that seem “moderate.” In wet or windy conditions, heat loss happens much faster—placing workers at risk of serious injury.
Cold-Related Health Effects
Frostnip
The mildest form of freezing injury where the outer layers of skin temporarily freeze. Affected areas (ears, nose, cheeks, fingers, toes) appear pale or white and may feel numb or firm. Skin may peel during recovery.
Frostbite
Occurs when tissue freezes or blood flow is severely restricted in cold conditions. Frostbitten skin is highly susceptible to infection, long-term nerve damage, and gangrene. Canadian winter wind chills can cause frostbite in as little as 5–10 minutes.
Hypothermia
As body temperature drops below 33°C, shivering stops and the worker may appear confused, lethargic, or unable to make decisions. At 27°C, coma can occur.
Important note for Canadian conditions: hypothermia can occur at temperatures above 10°C if workers are wet, such as during freezing rain, fall protection harness saturation, or immersion incidents. Heat loss in water is 25× faster than in air.
Factors That Affect Cold Tolerance
Cold affects every worker differently. Adaptation to cold can be reduced by:
- Poor general health or being overweight
- Age (45+)
- Medical conditions such as Raynaud’s phenomenon or chronic skin issues
- Alcohol, antidepressants, sedatives, or certain drugs
- Fatigue, dehydration, or poor nutrition
Lack of recent exposure or acclimatization to cold.
How Cold Stress Occurs on the Job
Exposure severity increases when several factors combine:
1. Cold Air Temperature
Measured in °C. Canadian OHS regulations do not set a universal “minimum working temperature,” but jurisdictions require employers to identify, assess, and control cold stress as part of their duty to protect workers.
2. Wind Speed
Wind strips away the thin layer of warm insulating air around the body. Environment and Climate Change Canada uses the Wind Chill Index, which helps identify frostbite risk levels.
Wind speed estimates:
- 8 km/h (5 mph): light flag moves
- 16 km/h (10 mph): flag fully extended
- 24 km/h (15 mph): lifts loose paper
- 32 km/h (20 mph): blowing snow and drifting begins
Wind chill warnings often state the expected time to frostbite on exposed skin.
3. Humidity / Wetness
Wet clothing dramatically accelerates heat loss. High humidity or wet snow makes the cold feel more intense. Freezing rain conditions, a common hazard in Ontario, Québec, and Atlantic Canada, create especially dangerous exposure scenarios.
4. Low Physical Activity
Lower activity = lower metabolic heat production.
5. Duration of Exposure
The longer the exposure, the higher the risk—especially without scheduled warm-up breaks.
6. Inadequate Clothing
Workers need layered, wind-resistant, waterproof, and insulated PPE. Wet clothing can make a worker colder than wearing no insulation at all.
Controlling the Hazard
Canadian OHS laws require employers to take every reasonable precaution to protect workers, including from environmental hazards like extreme cold. A detailed hazard assessment should be completed for any job with potential cold exposure.
Engineering Controls
- Heated shelters, trailers, warming tents
- Windbreaks, barriers, and enclosures
- Radiant heaters or contact heating pads for extremities
- Insulated tools, anti-slip matting, and ice management systems
Administrative Controls
- Schedule work during warmer parts of the day
- Use work-rest cycles based on wind chill and temperature
- ACGIH and Saskatchewan guidelines are commonly used across Canada
- ACGIH and Saskatchewan guidelines are commonly used across Canada
- Assign extra workers for rotation during extreme cold
- Monitor weather changes continuously
- Implement a buddy system to watch for early signs of cold stress
- Review workers’ medical limitations if relevant
- Provide warm, dry break areas and warm beverages
- Require prompt reporting of symptoms
Personal Protective Equipment (PPE)
- Layered clothing (base layer → mid-insulation → wind/waterproof shell)
- Insulated gloves and mitts, potentially with glove liners
- Thermal hats and balaclavas
- CSA-approved protective footwear with insulation and anti-slip soles
- High-visibility outerwear suitable for winter conditions
- Clothing considered part of your PPE program- not an optional accessory
- Extra dry clothing to change into if garments become wet.
Best Practices & Training Requirements
Workplaces with routine cold exposure should develop a Cold Stress Prevention Program that includes:
- Identification of high-risk tasks and work areas
- Job-specific procedures for cold, wind, and wet exposure
- Clear criteria for stopping work during extreme conditions
- Training on:
- Recognizing cold stress symptoms (frostbite, hypothermia, chilblains)
- Proper winter PPE and layering techniques
- Emergency procedures and first aid response
- Importance of hydration, nutrition, and warm-up routines
- Recognizing cold stress symptoms (frostbite, hypothermia, chilblains)
- Reinforcement that winter clothing is PPE and must meet minimum standards
- A documented monitoring and communication system during cold weather events
Canadian employers should also review applicable provincial guidelines, including:
- Ontario Ministry of Labour – Cold Stress Guidelines
- WorkSafeBC – Cold Stress Prevention
- WorkplaceNL – Working in Cold Environments Guide
- Saskatchewan’s Cold Stress Guidelines (used by ACGIH)
- Alberta OHS Code – Environmental Exposure Requirements
Final Thoughts
Canadian winters will always present challenges—but cold stress is preventable with planning, training, and proactive controls.
By recognizing the risks and implementing the right measures, employers and supervisors can protect workers, maintain productivity, and give winter the “cold shoulder.”