Ontario Mandates Workplace Heat Safety Standard

Summary#

Bill 36, the Heat Stress Act, 2025, would amend Ontario’s Occupational Health and Safety Act by adding a new part on heat stress. Its stated goal is to protect workers from heat-related illness and danger; that goal is not a guaranteed result.

  • The Minister must develop and implement a Worker Heat Protection Standard, consult Occupational Health Clinics for Ontario Workers and the Ontario Federation of Labour, publish the Standard online, and update it at least once every 12 months.
  • The Standard must set requirements for employers to address heat hazards, including engineering controls, limits on exposure, employer-paid breaks and protective equipment, workplace policies and programs, heat assessments, and access to cool drinking water or an adequate alternative.
  • Employers must ensure training for employees and supervisors under the Standard. They must also ensure that health and safety representatives and committee members receive approved heat-stress training from an approved provider.
  • Workers must receive their regular pay for periods required by the Standard, including rest, breaks, medical removal protection and training. Required training and certain other materials must be available in plain language, with language and literacy needs considered.
  • For the first five years after the Standard is implemented, the Minister must report annually to the Legislature on heat-related illness and mortality figures and the Ministry’s enforcement activities.

What it means for you#

  • Workers: If the Standard requires a break, training or medical removal period, you must receive your regular rate of pay for that time. The Standard must also address heat controls, assessments, hydration, training and protective equipment.
  • Employers: You would have to meet the requirements set out in the Standard, including developing and reviewing a heat policy and program with input from the workplace health and safety representative or committee. The bill also requires employers to ensure specified training.
  • Health and safety representatives and committee members: Employers must ensure you receive heat-stress training that meets the bill’s content and approval requirements. Employers must provide you with the results of heat-stress assessments.
  • Minister and Ministry: The Minister must develop, implement and update the Standard. The Ministry must report on its enforcement activity for five years after implementation.
  • General public: The bill does not directly change taxes, create a new agency, or set out a new worker application or complaint process.

Money#

No cost information is in the available material.

  • Employers would have to pay for breaks and protective equipment when required by the Standard, and pay workers their regular rate for periods covered by the pay rule.
  • The bill requires the Minister and Ministry to develop, update and report on the Standard, but gives no cost estimate or staffing figure.
  • No publicly available information is provided about total employer costs, government spending, or how the costs would be funded.

What is unclear#

  • The bill does not set the specific heat limits, assessment methods, or required assessment frequency. Those details would be in the Standard or other rules.
  • It does not say exactly what breaks, protective equipment or other controls employers must provide in particular conditions. The Standard would set the requirements.
  • The bill says the Standard must be implemented within 12 months after the new part comes into force, and the Act would come into force 12 months after Royal Assent. The actual dates depend on when Royal Assent occurs and when the Standard is implemented.
  • The bill text does not explain how the new Standard would interact with existing heat-protection requirements. The supplied material does not include the current Occupational Health and Safety Act, so existing duties and standards could not be verified.
  • It is unclear how the Ministry would enforce the new Standard beyond the requirement to report on enforcement activities.

Case for#

  • A province-wide Standard could set consistent heat protections for different kinds of workplaces.
  • The required contents cover several ways to address heat hazards, including engineering controls, work practices, water, assessments and protective equipment.
  • Paid periods required by the Standard could help workers take required breaks or receive training without losing regular pay.
  • Annual reports for five years could give the Legislature information about heat-related illness, deaths and enforcement.

Case against#

  • Key requirements would be set later in the Standard, so the bill itself does not show exactly what employers must do in specific heat conditions.
  • The bill requires implementation within a set period, but does not provide a cost estimate or say how the Minister’s work would be funded.
  • Employers would have to meet requirements for assessments, policies, training and protections, but the bill does not estimate the related costs or explain how smaller workplaces would manage them.
  • The bill names two organizations for consultation with the Ministry, but does not specify how workers or other affected groups would be involved in developing or updating the Standard.