Heat Stress at Work in Canada: Employer Safety Checklist for Summer 2026

A practical Canadian employer guide to heat stress at work in summer 2026. Covers employer duties, indoor and outdoor heat risks, warning signs, prevention steps, a daily supervisor checklist, a sample workplace heat stress policy template, and the 2027 federal thermal stress compliance deadline.

Overview

Last reviewed: June 2026  |  Jurisdiction: Canada (all provinces and territories, plus federal)  |  Applies to: Canadian employers in hospitality, construction, warehousing, landscaping, delivery, retail, manufacturing, agriculture, healthcare, and office settings.

Heat stress is no longer just an outdoor construction issue. In Canada, employers now need to think about heat risk in restaurants, kitchens, warehouses, delivery work, farms, landscaping, manufacturing, retail spaces, healthcare settings, and offices where cooling is poor or unreliable.

Summer heat can affect workers quickly. A worker may start a shift feeling normal, but as the day gets hotter, the body may struggle to cool itself. This can lead to fatigue, dizziness, muscle cramps, poor concentration, nausea, fainting, heat exhaustion, or heat stroke.

For employers, heat stress is both a health and safety issue and a business risk. The good news is that most heat-related workplace incidents can be reduced with practical planning. This guide explains what Canadian employers should know for summer 2026 and provides a sample heat stress policy template that can be adapted for many workplaces.

This article provides general workplace safety information for Canadian employers. It is not legal advice. Employers should confirm the specific occupational health and safety requirements that apply in their province, territory, sector, and workplace.

Table of Contents

  1. What Is Heat Stress at Work?
  2. Why Heat Stress Matters in Summer 2026
  3. Which Workplaces Are Most at Risk?
  4. Employer Duties: What Canadian Employers Should Understand
  5. Federal Thermal Stress Update: Important 2027 Compliance Note
  6. Indoor Heat Stress vs Outdoor Heat Stress
  7. Heat Stress Risk Factors Employers Should Assess
  8. Warning Signs Managers and Supervisors Should Know
  9. What to Do When a Worker Shows Heat Stress Symptoms
  10. How to Prevent Heat Stress at Work
  11. What a Heat Stress Policy Should Include
  12. Sample Heat Stress Policy Template
  13. Training Checklist for Workers and Supervisors
  14. Daily Supervisor Heat Stress Checklist
  15. Industry-Specific Examples
  16. Common Mistakes Employers Should Avoid
  17. Practical Summer 2026 Action Plan
  18. Frequently Asked Questions
  19. Suggested Official Sources

1. What Is Heat Stress at Work?

Heat stress happens when the body gains more heat than it can safely release. The body normally cools itself by sweating and increasing blood flow to the skin. But in a hot workplace — especially when the air is humid, the work is physically demanding, or the worker is wearing heavy protective clothing — sweating may not be enough.

Environmental heat

This includes hot weather, direct sunlight, humidity, radiant heat from pavement or roofs, poor ventilation, ovens, boilers, dryers, industrial equipment, kitchens, and hot vehicles.

Work-related heat

The harder the body works, the more heat it produces. Lifting, carrying, digging, cleaning, loading, moving quickly, climbing stairs, working on roofs, or performing repetitive physical tasks can increase the worker's internal heat load.

Worker-specific factors

Some workers may be more vulnerable because they are new to the job, not used to working in heat, returning after time away, dehydrated, tired, wearing heavy clothing or PPE, taking certain medications, or dealing with a health condition that affects heat tolerance.

Temperature alone does not tell the full story. A workplace can become risky at lower temperatures if humidity is high, air movement is poor, the job is physically demanding, or the worker is wearing protective clothing that traps heat.

2. Why Heat Stress Matters in Summer 2026

Heat stress should be a priority for employers in summer 2026 for four main reasons.

1. Heat is a foreseeable workplace hazard

For many workplaces, summer heat is not a surprise. It is seasonal, predictable, and manageable with proper planning. If employees work outdoors, near hot equipment, in poorly ventilated spaces, in vehicles, in kitchens, in warehouses, or while wearing heavy PPE, heat stress should be part of the workplace hazard assessment.

2. Heat affects safety, not only comfort

Heat stress is not just about discomfort. It can reduce attention, slow reaction time, increase fatigue, affect judgment, and raise the risk of other workplace incidents. A hot worker may be more likely to make mistakes while driving, using equipment, climbing ladders, handling tools, moving materials, or working near co-workers.

3. Indoor heat stress is often missed

Many employers think heat stress is only an outdoor issue. That is not correct. Indoor workplaces can become hazardous when heat builds up or ventilation is poor. Restaurant kitchens, bakeries, laundries, factories, warehouses, mechanical rooms, retail stores, and offices without reliable cooling can all create heat stress risk.

4. Federal rules are changing for 2027

In January 2026, the federal government finalized new thermal stress requirements for federally regulated workplaces. These requirements are not yet in force for summer 2026. They are set to take effect on January 30, 2027. This gives federally regulated employers time to prepare.

Employers planning major outdoor events — such as festivals, tournaments, or site visits — should also review our Calgary Stampede HR Compliance Guide and FIFA World Cup 2026 HR Compliance Guide for event-specific heat and OHS considerations.

3. Which Workplaces Are Most at Risk?

Any workplace can have heat stress risk, but some workplaces need extra attention.

Outdoor workplaces

Outdoor workers may face direct sunlight, humidity, hot pavement, limited shade, and changing weather conditions.

  • Construction and roofing
  • Landscaping and road work
  • Farming and agriculture
  • Delivery and courier work
  • Waste collection
  • Outdoor events and security patrols
  • Parking lot work
  • Utilities and maintenance
  • Municipal work

Indoor workplaces without proper cooling

Indoor heat stress can be overlooked because employers may assume heat risk only applies outdoors. Indoor workplaces can become hazardous when heat builds up or ventilation is poor.

  • Restaurant kitchens and bakeries
  • Warehouses and factories
  • Laundries and dry cleaners
  • Manufacturing and food processing
  • Mechanical rooms and workshops
  • Retail stores with poor air conditioning
  • Offices with broken or weak cooling

Mobile and vehicle-based work

Drivers and mobile workers may experience heat stress when loading, unloading, waiting in hot vehicles, wearing uniforms, or working in areas without shade or cooling. This includes delivery drivers, moving crews, home service technicians, HVAC technicians, utility workers, and mobile healthcare workers.

Work involving PPE or uniforms

PPE can protect workers from one hazard while increasing heat risk. Employers should assess heat risk carefully when workers wear coveralls, impermeable protective clothing, respirators, gloves, helmets, face shields, high-visibility gear, heavy uniforms, chemical protection, or fire-resistant clothing. PPE may reduce the body's ability to cool itself — heat stress can occur even when the air temperature does not seem extreme.

4. Employer Duties: What Canadian Employers Should Understand

Heat stress requirements vary by jurisdiction. Canada does not have one single heat-stress rule that applies identically to every employer. However, Canadian employers should understand the general pattern.

Most occupational health and safety systems expect employers to:

For heat stress, this means employers should not wait until someone collapses or files a complaint. Employers should have a plan before the hottest period of the year.

Some provinces and territories may have more specific heat stress requirements than others. Some jurisdictions use specific assessment methods or exposure control expectations. Others rely more heavily on general employer duties and hazard assessment requirements.

Provincially and territorially regulated employers

Most Canadian employers are provincially or territorially regulated. Employers should generally ask:

Alberta employers

Alberta has a detailed OHS framework that covers employer hazard assessment and control obligations. See our Alberta Workplace Safety & OHS Requirements guide for a broader overview of Alberta employer obligations.

Ontario employers — watch Bill 36

Bill 36, the Heat Stress Act, 2025, was introduced in the Ontario Legislature as a private member's bill and remains a proposed bill as of this article's June 2026 update. It should not be treated as current law unless it is passed and brought into force. Ontario employers should continue to treat heat stress as a workplace hazard under existing occupational health and safety duties while monitoring whether Bill 36 progresses.

5. Federal Thermal Stress Update: Important 2027 Compliance Note

Federally regulated employers include certain industries such as banking, telecommunications, interprovincial transportation, airlines, railways, marine shipping, postal services, federal Crown corporations, and other federally regulated sectors.

Key point for summer 2026

The federal government has finalized new thermal stress requirements, but they are not yet in force. They are set to come into force on January 30, 2027.

Which federal regulations are affected?

The 2026 federal amendments add new thermal stress provisions to the Canada Occupational Health and Safety Regulations and parallel regulations for certain sectors. The provision is section 10.19.3. Parallel provisions include:

What will federally regulated employers need to do from 2027?

Once in force, the federal thermal stress provisions will require employers to develop and implement procedures to reduce the risk of thermal stress, developed in consultation with the applicable policy committee, workplace committee, or health and safety representative.

The procedures will need to include:

For heat stress, the federal approach is connected to ACGIH screening criteria using effective wet bulb globe temperature (WBGTeff) for acclimatized and unacclimatized workers. Employers should be careful not to treat humidex as the federal benchmark under these new provisions.

Thermal stress incident records (from 2027)

Once in force, federally regulated employers will also need to record thermal stress incidents. The record must include: date and time of the incident; thermal conditions at the time; protective measures in effect; protective measures actually used; symptoms experienced; and treatment given.

Practical takeaway for summer 2026

Use summer 2026 as a preparation period. Even though the new thermal stress provisions are not yet in force, employers should begin reviewing: current heat stress procedures; hazard prevention programs; committee consultation processes; heat monitoring methods; supervisor and worker training; work-rest cycles; acclimatization practices; PPE and clothing rules; incident reporting forms; and documentation practices.

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6. Indoor Heat Stress vs Outdoor Heat Stress

Employers should treat indoor and outdoor heat stress differently because the causes and controls may be different.

FactorOutdoor Heat StressIndoor Heat Stress
Main sourcesWeather, direct sun, humidity, hot pavement, reflective surfaces, lack of shadeEquipment, ovens, dryers, poor ventilation, hot air, humidity, crowded spaces, failed air conditioning
Key riskConditions can change throughout the day. A task safe at 8:00 a.m. may become risky at 2:00 p.m.Workers and managers may not notice the risk early because there is no visible weather event.
Key controlsEarly start times, shade, cooling stations, rotating workers, reducing task intensity, postponing non-urgent work, buddy systemRepairing air conditioning, fans, improved ventilation, local exhaust near heat-producing equipment, cool rest areas, rotating workers, scheduling hot tasks at cooler times
Indoor heat stress can be serious because workers and managers may not notice the risk early. A kitchen, warehouse, laundry, or workshop can become dangerous even when there is no formal outdoor heat warning.

7. Heat Stress Risk Factors Employers Should Assess

A good heat stress assessment should look at more than the weather forecast. Employers should review all the factors that affect heat load.

Environmental factors

  • Air temperature and humidity
  • Direct sunlight and radiant heat
  • Air movement and ventilation
  • Shade availability
  • Indoor cooling systems
  • Heat from vehicles or enclosed spaces

Workload factors

  • How physically demanding the task is
  • How long the worker performs the task
  • Whether workers can slow down or rotate tasks
  • Whether heavy lifting, climbing, or fast movement is required
  • Whether the task can be delayed, shortened, or moved

Clothing and PPE factors

  • Whether clothing traps heat
  • Whether PPE prevents sweat evaporation
  • Whether gloves, helmets, or respirators increase heat load
  • Whether lighter alternatives are possible without reducing safety

Worker factors

  • New, temporary, or seasonal workers
  • Young or inexperienced workers
  • Workers returning after vacation, illness, or time away
  • Workers who are not acclimatized
  • Workers working alone
  • Workers who may be dehydrated or fatigued

Work organization factors

  • Shift length and overtime
  • Break frequency and location
  • Access to water
  • Staffing levels and pace of work
  • Production pressure
  • Supervisor coverage
  • Emergency response readiness
  • Communication methods for mobile or outdoor workers
Heat stress is often made worse when workers feel pressured to "push through." A good policy should make it clear that workers can report heat symptoms early without being punished or judged.

Employers should not ask workers to disclose private medical information unless legally appropriate. However, employers can train all workers to understand that some personal factors can increase heat risk and encourage workers to speak with a supervisor if they need accommodation or support.

Sources

8. Warning Signs Managers and Supervisors Should Know

Supervisors should know the early signs of heat stress and the serious warning signs of heat illness.

StageSigns and SymptomsImmediate Action
Early warningHeavy sweating, muscle cramps, fatigue, weakness, dizziness, headache, nausea, thirst, irritability, reduced concentration, feeling faint, unusual tiredness, slower work pace, mistakes or confusionMove to cooler area. Monitor closely. Do not tell the worker to simply drink water and continue.
Heat exhaustionHeavy sweating, weakness, dizziness, headache, nausea, muscle cramps, pale or cool or moist skin, fast heartbeat, intense thirst, feeling faint, high body temperatureMove to cooler area. Get first aid or medical help. Do not leave the worker alone. Do not return to hot work the same day.
Heat stroke ⚠Confusion, disorientation, loss of consciousness, seizures, very high body temperature, hot skin or heavy sweating, unusual behaviour, irregular or fast heartbeatCall 911 immediately. Do not wait to see if the worker improves.

Heat stroke is a medical emergency

Call emergency medical services immediately if heat stroke is suspected. Do not wait to see if the worker improves on their own.

9. What to Do When a Worker Shows Heat Stress Symptoms

Every workplace should have a simple heat stress response procedure. Supervisors should know what to do before an incident happens.

If a worker shows early symptoms

  1. Stop the task.
  2. Move the worker to a cooler or shaded area.
  3. Do not leave the worker alone.
  4. Provide cool water if the worker is alert and able to drink.
  5. Remove unnecessary PPE or extra clothing if safe to do so.
  6. Use cooling methods such as fans, cool cloths, misting, or ice packs if available.
  7. Notify a supervisor or first aid attendant.
  8. Document the incident and review whether controls need to be improved.

If heat exhaustion is suspected

  1. Move the worker to a cooler place immediately.
  2. Get first aid or medical help.
  3. Stay with the worker.
  4. Encourage small sips of cool water only if the worker is conscious and able to drink safely.
  5. Cool the worker with wet cloths, cool water, fans, or ice packs.
  6. Do not send the worker back to hot work the same day unless medically cleared and safe.
  7. Investigate what caused the heat stress.

If heat stroke is suspected

  1. Call 911 immediately.
  2. Move the worker to a cooler or shaded area if it is safe to do so.
  3. Stay with the worker until emergency help arrives.
  4. Remove unnecessary clothing or PPE if safe.
  5. Cool the worker quickly using water, wet cloths, fans, or ice packs.
  6. Do not force the worker to drink.
  7. Notify management and follow incident reporting procedures.
A heat stress incident should always trigger a review. Ask what failed: Was there not enough water? Were breaks too short? Was the work too intense? Was the worker new or not acclimatized? Was the supervisor trained? Were workers afraid to speak up?

In a heat stress situation, avoid alcoholic and caffeinated drinks. If a worker is confused, unconscious, vomiting, or not able to drink safely, do not force fluids. Get emergency medical help immediately if heat stroke is suspected.

10. How to Prevent Heat Stress at Work

Employers should use the hierarchy of controls. This means the most effective controls should be considered first.

1. Elimination or substitution

The best control is to remove the heat hazard when possible.

2. Engineering controls

Engineering controls physically change the workplace or equipment to reduce heat exposure.

3. Administrative controls

Administrative controls change how work is planned and supervised.

4. PPE and clothing

PPE should not be the only heat stress control. However, clothing choices can reduce risk when properly selected — lightweight breathable clothing, cooling towels or vests, sun hats or neck shades for outdoor workers, and review of whether PPE can be changed without reducing safety. Do not remove PPE if it protects against another serious hazard.

5. Water and hydration

Workers should have easy access to cool drinking water. Water should be close enough that workers can drink regularly without leaving the work area for long periods. Hydration is important, but water alone is not enough. A complete heat stress plan also needs cooling, breaks, workload control, training, and emergency response.

6. Rest breaks and cooling areas

Rest breaks should allow workers to cool down, not just stop working for a few minutes in another hot area. A proper cooling area may include shade, air conditioning, fans, cool drinking water, seating, reduced crowding, first aid supplies, communication access, and supervisor visibility.

7. Acclimatization

Acclimatization means giving the body time to adjust to working in heat. This is especially important for new workers, seasonal workers, temporary workers, workers returning after vacation or illness, and workers moved from cool indoor work to hot outdoor work. A simple approach is to start with lighter exposure and increase gradually. Do not expect a new or returning worker to perform a full hot-weather workload on the first day.

11. What a Heat Stress Policy Should Include

A heat stress policy does not need to be complicated. It should be clear, practical, and easy for supervisors to use. Your heat stress policy should include the following sections.

Policy SectionWhat to Include
PurposeExplain that the policy is designed to prevent heat-related illness and protect workers during hot conditions.
ScopeState who the policy applies to — employees, supervisors, temporary workers, contractors, mobile workers, outdoor and indoor workers exposed to heat.
DefinitionsHeat stress, heat exhaustion, heat stroke, acclimatization, cooling area, work-rest cycle, WBGT (if used).
Roles and responsibilitiesWhat employer, supervisors, and workers must each do.
Risk assessment processExplain how heat risk will be assessed — temperature, humidity, workload, direct sunlight, radiant heat, ventilation, PPE, acclimatization, work duration.
Monitoring processWhen and how the workplace will monitor heat conditions — weather forecasts, indoor temperature readings, WBGT where appropriate.
Control measuresEngineering controls, administrative controls, water, shade, cooling areas, work-rest cycles, and PPE adjustments.
Acclimatization planHow new and returning workers will be gradually introduced to hot work.
TrainingConfirm workers and supervisors will be trained before or during hot weather periods.
Emergency responseExplain what to do when a worker shows symptoms of heat exhaustion or heat stroke.
Reporting and documentationHow workers report concerns and how heat-related incidents will be documented and reviewed.
Annual reviewReview the policy before every summer and after any heat-related incident.

Looking for other essential employment policy templates? See our guide to 9 Essential Employment Policy Templates Every Small Canadian Business Needs.

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12. Sample Heat Stress Policy Template

The following sample template is provided for general information and should be customized for your workplace, province, territory, industry, and hazards. Employers should review the final version with a qualified health and safety professional or legal advisor before using it as an official workplace policy.

Sample Workplace Heat Stress Prevention Policy

1. Policy Statement

[Company Name] is committed to protecting workers from heat stress and heat-related illness. Heat stress can occur when workers are exposed to hot working conditions, high humidity, direct sunlight, radiant heat, poor ventilation, physical exertion, or protective clothing and equipment that limits the body's ability to cool itself. The purpose of this policy is to identify, assess, control, and respond to heat stress hazards in the workplace.

2. Scope

This policy applies to all workers, supervisors, managers, temporary workers, contractors, and visitors who may be exposed to heat stress hazards while performing work for [Company Name]. This includes outdoor work in hot weather; work near hot equipment, ovens, machinery, dryers, or boilers; work in vehicles or enclosed spaces; physically demanding work; work requiring heavy uniforms or PPE; and work in areas with poor ventilation or limited cooling.

3. Definitions

  • Heat stress — the body's overall heat load from environmental heat, physical work, and clothing or PPE.
  • Heat exhaustion — heavy sweating, weakness, dizziness, headache, nausea, muscle cramps, faintness, or fast heartbeat.
  • Heat stroke — a medical emergency; may include confusion, loss of consciousness, seizures, very high body temperature, or unusual behaviour.
  • Acclimatization — the process by which a worker's body gradually adjusts to working in hot conditions.
  • Cooling area — a shaded, air-conditioned, ventilated, or otherwise cooler location where workers can rest and recover.
  • Work-rest cycle — a planned schedule that alternates work periods with rest or cooling periods.
  • WBGT — wet bulb globe temperature, a heat stress assessment method considering temperature, humidity, radiant heat, and air movement.

4. Responsibilities

Employer responsibilities:

  • Identify work activities and locations where heat stress may occur
  • Assess heat stress risks before and during hot work conditions
  • Implement controls to reduce heat exposure
  • Provide access to cool drinking water and shaded, ventilated, or cooled rest areas
  • Provide training to workers and supervisors
  • Monitor heat conditions using appropriate methods
  • Support acclimatization for new and returning workers
  • Ensure supervisors have authority to adjust work, breaks, and schedules
  • Respond promptly to reported symptoms and investigate incidents
  • Review this policy at least annually and after any heat-related incident

Supervisor responsibilities:

  • Review heat stress risks before and during the shift
  • Monitor workers for signs and symptoms of heat stress
  • Ensure workers have access to water and cooling areas
  • Adjust work pace, breaks, tasks, or schedules when heat risk increases
  • Pay special attention to new, returning, temporary, or unacclimatized workers
  • Respond immediately if a worker reports or shows symptoms
  • Arrange first aid or emergency medical help when required
  • Document heat stress concerns, symptoms, incidents, and corrective actions
  • Stop or reschedule work when conditions become unsafe

Worker responsibilities:

  • Follow this policy and all heat stress procedures
  • Drink water regularly during hot work conditions
  • Use cooling areas and rest breaks as directed
  • Report heat stress symptoms and hazards early
  • Watch co-workers for signs of heat stress
  • Use required protective clothing and equipment properly
  • Participate in heat stress training

5. Heat Stress Hazard Assessment

[Company Name] will assess heat stress risk when workers may be exposed to hot conditions. The assessment may consider: air temperature; humidity; direct sunlight; radiant heat from equipment, pavement, roofs, ovens, or machinery; air movement and ventilation; workload and physical effort; duration of exposure; clothing, uniforms, and PPE; availability of water; availability of shade or cooling areas; worker acclimatization; whether workers are working alone; and previous heat-related concerns or incidents. Where required or appropriate, [Company Name] may use methods such as WBGT, indoor temperature readings, weather forecasts, or other recognized heat stress assessment methods.

6–9. Control Measures, Acclimatization, Training, Emergency Response

[Customize using the controls, acclimatization steps, training topics, and emergency response procedures described in this guide.]

10. Reporting and Documentation

Workers must report heat stress symptoms or unsafe heat conditions to a supervisor as soon as possible. Supervisors must document heat-related concerns, symptoms, incidents, and corrective actions. Records may include date and time; work location; weather or workplace conditions; job task being performed; symptoms reported or observed; controls in place and actually used; first aid or treatment provided; whether emergency services were contacted; corrective actions taken; and follow-up required.

11. Work Refusal and Non-Retaliation

[Company Name] will not discipline, penalize, or retaliate against a worker for reporting heat stress symptoms, reporting a heat stress hazard, requesting help, or exercising rights under applicable occupational health and safety law.

12. Review

This policy will be reviewed at least once per year before the hot weather season; after any heat stress incident; when work processes, equipment, staffing, or workplace conditions change; and when legal or regulatory requirements change.

Policy owner: [Name / Position]  |  Effective date: [Date]  |  Next review date: [Date]  |  Approved by: [Name / Position]

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13. Training Checklist for Workers and Supervisors

Training should be simple and practical. Workers should leave the training knowing what heat stress looks like, how to prevent it, and what to do if symptoms appear.

Worker training topics

  • □What heat stress is and why it is dangerous
  • □Early signs and symptoms
  • □Heat exhaustion symptoms
  • □Heat stroke symptoms
  • □How to report symptoms
  • □Where water is available
  • □Where cooling areas are located
  • □Break procedures
  • □Acclimatization expectations
  • □Buddy system rules
  • □PPE and clothing requirements
  • □Emergency response steps

Supervisor training topics

  • □How to identify heat stress risk
  • □How to monitor workers
  • □How to adjust breaks and workload
  • □How to respond to symptoms
  • □How to call for medical help
  • □How to document incidents
  • □How to support new and returning workers
  • □How to handle workers working alone
  • □How to stop or reschedule unsafe work
  • □How to communicate heat stress controls at shift start meetings
Supervisors should be clearly told that heat stress controls are not optional. If conditions become unsafe, productivity should not be placed above worker safety.

14. Daily Supervisor Heat Stress Checklist

Use this checklist during hot weather.

Before the shift
  • □Check the weather forecast and workplace heat conditions.
  • □Check indoor temperature and ventilation where applicable.
  • □Identify high-risk tasks for the day.
  • □Identify workers who are new, returning, or not acclimatized.
  • □Confirm water is available and close to the work area.
  • □Confirm shade or cooling areas are ready.
  • □Confirm fans, ventilation, misting, or cooling systems are working.
  • □Review work-rest schedules and adjust heavy work to cooler times if possible.
  • □Plan worker rotation.
  • □Confirm communication methods for mobile or isolated workers.
  • □Remind workers to report symptoms early.
During the shift
  • □Monitor workers for signs of heat stress.
  • □Encourage regular water intake.
  • □Make sure workers use cooling areas.
  • □Add breaks when conditions get hotter.
  • □Rotate workers away from hot tasks. Reduce work pace if needed.
  • □Check on workers wearing PPE and workers working alone.
  • □Watch for fatigue, confusion, dizziness, nausea, cramps, or unusual behaviour.
  • □Stop work if conditions become unsafe.
After the shift
  • □Ask supervisors and workers if heat controls worked.
  • □Record heat-related concerns or symptoms.
  • □Refill supplies for the next day.
  • □Review any first aid reports.
  • □Update the next day's schedule if more heat is expected.
  • □Report unresolved hazards to management.
  • □Improve the plan before the next hot shift.

15. Industry-Specific Examples

The following examples provide practical starting points. Employers should customize controls for their specific workplace, hazards, staffing, and jurisdiction.

Restaurants and commercial kitchens

Restaurant workers may face heat from ovens, grills, fryers, dishwashing areas, poor ventilation, humidity, and fast-paced work.

  • Improve kitchen ventilation and maintain exhaust systems
  • Provide cool water and allow short cooling breaks
  • Rotate workers away from the hottest stations
  • Schedule prep work during cooler periods
  • Review uniforms for summer comfort
  • Train supervisors to watch for dizziness, nausea, and fatigue

Warehouses

Warehouses can trap heat, especially near loading docks, mezzanines, roofs, and areas with poor airflow.

  • Use fans and improve ventilation; use air curtains or dock controls where possible
  • Provide cool rest areas and water close to work zones
  • Rotate workers performing heavy picking or loading
  • Schedule heavy loading earlier in the day
  • Monitor indoor temperature during heat waves

Construction

Construction workers face sunlight, hot surfaces, physical exertion, PPE, and changing outdoor conditions.

  • Start earlier when possible; provide shade and cooling stations
  • Rotate high-exertion tasks; reduce roof or asphalt work during peak heat
  • Use buddy checks and provide water coolers close to crews
  • Train forepersons to stop work when needed

Landscaping

Landscaping workers may be exposed to direct sun, reflective heat from stone or pavement, physically demanding tasks, and limited shade.

  • Schedule heavy work in the morning; provide portable shade
  • Use mechanized tools where possible; rotate tasks
  • Reduce work on reflective surfaces during peak heat
  • Check on workers frequently

Retail and offices

Retail and office heat stress may happen when air conditioning fails, windows increase radiant heat, or workers cannot leave their stations.

  • Repair cooling systems promptly; use fans where safe
  • Move workers away from hot areas; adjust dress codes during heat
  • Provide water and allow cooling breaks
  • Have a plan for closing or modifying operations if indoor temperatures become unsafe

Delivery and mobile work

Drivers and mobile workers may face hot vehicles, outdoor unloading, time pressure, and limited access to water or washrooms.

  • Provide insulated water containers; allow cooling stops
  • Avoid unnecessary waiting in hot vehicles
  • Encourage early reporting; use check-ins for workers alone
  • Consider heat risk when assigning heavy deliveries
  • Train workers not to push through symptoms

16. Common Mistakes Employers Should Avoid

The following are common heat stress planning errors. Avoiding them can significantly reduce risk.

1

Waiting for an official heat warning

Heat stress can happen before a public heat warning is issued. Public warnings are useful, but they may not reflect the actual heat load inside a workplace or during physically demanding work.

2

Looking only at temperature

Temperature is only one factor. Humidity, sunlight, radiant heat, workload, PPE, air movement, and acclimatization all matter.

3

Assuming indoor workers are safe

Indoor workplaces can become very hot, especially kitchens, warehouses, laundries, factories, and offices without proper cooling.

4

Giving water but not breaks

Water is important, but workers also need time and a cool place to recover. Hydration alone does not remove heat stress risk.

5

Ignoring new and returning workers

Workers who are not acclimatized can be at higher risk. A full workload on the first hot day can be dangerous.

6

Treating heat symptoms as weakness

Workers may stay silent if they think symptoms will be mocked or punished. Employers should create a culture where early reporting is expected and respected.

7

Forgetting workers who work alone

Workers who work alone may not have someone nearby to notice confusion, dizziness, or collapse. Employers should increase check-ins during hot conditions.

8

Not documenting controls

If an incident happens, employers should be able to show what they did. Keep records of training, inspections, water availability, schedule changes, incidents, and corrective action.

9

Copying a policy without customizing it

A generic heat stress policy may not match the real risks in the workplace. A kitchen, a warehouse, a delivery route, a landscaping crew, and an office with poor cooling may need different controls.

10

Treating the 2027 federal amendments as already in force

For federally regulated workplaces, the new thermal stress provisions have been finalized but are not yet in force for summer 2026. Employers should prepare now, but the provisions are not yet enforceable.

17. Practical Summer 2026 Action Plan

Here is a simple action plan employers can use before and during summer 2026.

1

Identify heat-risk roles

List all jobs that may involve heat exposure. Include outdoor, indoor, mobile, and PPE-heavy roles.

2

Review previous incidents

Look at last summer's first aid reports, complaints, near misses, absenteeism, and supervisor notes. Heat-related issues may not have been labelled as "heat stress."

3

Create or update your heat stress policy

Use the policy sections in this guide. Keep it simple enough that supervisors will actually use it.

4

Train supervisors first

Supervisors make daily decisions. They need authority to add breaks, rotate workers, slow work, and stop unsafe tasks.

5

Train workers

Training should be short, practical, and repeated during hot weather. Use toolbox talks, posters, shift huddles, and onboarding.

6

Prepare water and cooling areas

Do this before the first major hot period. Do not wait until workers complain.

7

Create an acclimatization plan

Have a specific process for new workers, seasonal workers, temporary workers, and people returning after time away.

8

Adjust schedules

Move heavy tasks to cooler times when possible. Build flexibility into the workday.

9

Monitor conditions

Use weather forecasts, indoor temperature checks, WBGT where appropriate, and supervisor observations.

10

Review and improve

After hot days, ask what worked and what did not. Improve the plan during the summer, not after the season ends.

11

Prepare for federal 2027 requirements if applicable

Federally regulated employers should use summer 2026 to review whether their procedures, training, monitoring, and incident reporting will be ready before the January 30, 2027 federal thermal stress requirements take effect.

18. Frequently Asked Questions

Is there a maximum legal workplace temperature in Canada?

In many workplaces, there is no simple single maximum temperature that applies to every situation. Heat stress risk depends on humidity, sunlight, radiant heat, workload, clothing, PPE, air movement, acclimatization, and rest breaks. Some jurisdictions may adopt or refer to specific exposure criteria or assessment methods. Employers should check the rules that apply in their jurisdiction and assess the actual risk in their workplace.

Can heat stress happen indoors?

Yes. Heat stress can happen indoors in kitchens, warehouses, factories, laundries, workshops, retail spaces, offices with poor cooling, and any workplace where heat builds up or ventilation is poor.

Is water enough to prevent heat stress?

No. Water is important, but it is not enough by itself. Employers may also need shade, cooling areas, work-rest cycles, schedule changes, ventilation, task rotation, reduced workload, training, and emergency response procedures.

What should a supervisor do if a worker feels dizzy or nauseous in the heat?

The supervisor should stop the work, move the worker to a cooler or shaded area, stay with the worker, provide water if the worker is alert and able to drink safely, cool the worker, and get first aid or medical help if symptoms are serious or do not improve. If heat stroke is suspected, call emergency medical services immediately.

Do new workers need special heat precautions?

Yes. New workers, seasonal workers, temporary workers, and workers returning after time away may not be acclimatized. Employers should gradually increase heat exposure and workload instead of assigning a full hot-weather workload immediately.

Should employers have a written heat stress policy?

A written heat stress policy is strongly recommended. It helps supervisors understand what to do, helps workers know how to report symptoms, and helps employers show that they planned for a foreseeable workplace hazard. See our policy templates guide for more essential employment policy templates.

Does Ontario have a specific Heat Stress Act in force?

As of this article's June 2026 update, Ontario Bill 36, the Heat Stress Act, 2025, has been introduced as a private member's bill but should not be treated as law unless it is passed and brought into force. Ontario employers should continue to manage heat stress under existing occupational health and safety duties and monitor legislative developments.

Are the new federal thermal stress rules in force for summer 2026?

No. The federal thermal stress requirements were finalized and registered in January 2026, but they are not yet in force for summer 2026. They are set to come into force on January 30, 2027.

What should federally regulated employers do in summer 2026?

Federally regulated employers should use summer 2026 as a preparation period. They should review heat stress procedures, committee consultation, WBGT-based assessment needs, training, work-rest practices, acclimatization, protective equipment, and incident reporting before the 2027 compliance date.

Final Employer Takeaway

Heat stress is predictable, preventable, and serious. Employers should not treat summer heat as a minor comfort issue. It can affect worker health, decision-making, concentration, physical performance, and overall workplace safety.

For summer 2026, Canadian employers should take a practical approach:

For federally regulated employers, summer 2026 is also a preparation window for the finalized federal thermal stress provisions set to take effect on January 30, 2027.

A simple heat stress policy can protect workers and help employers show that they took reasonable precautions. The best time to prepare is before the hottest day of the year.

This article is for general information only and is not legal advice. Employers should consult qualified legal counsel or the relevant government authority before making compliance decisions.

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Key Takeaways

Disclaimer: This article provides general workplace safety information for Canadian employers. It is not legal advice. Employers should confirm the specific occupational health and safety requirements that apply in their province, territory, sector, and workplace.