Ontario proposes ‘stand-alone’ heat stress legislation

• introduce heat stress exposure limits based on the ACGIH method
• provide for the use of other methods to assess a worker’s risk of exposure to heat stress
• require employers to identify and implement measures and procedures to control heat exposures based on the “hierarchy of controls”, and
• require employers to provide worker information and instruction on recognizing the signs and symptoms of heat-related illnesses and the measures to protect themselves

Recently, the World Meteorological Organisation (WMO) and the European Commission's Copernicus Climate Change Service confirmed that July registered the warmest three-week period on record, the three hottest days on record, as well as the highest-ever ocean temperatures at this time of the year.

What does the heat stress legislation include?

Under Ontario’s MLITSD proposal:

1. All employers would have a duty to take all measures reasonably necessary in the circumstances to protect workers from exposure to hazardous thermal conditions that may result in a heat-related illness or a worker's core body temperature exceeding 38°C (100°F).
2. Compliance with heat stress exposure limits for light to very heavy work loads in accordance with methods used to determine heat exposures will be required.
3. The use of methods other than the American Conference of Governmental Industrial Hygienists (ACGIH) method to assess a worker’s exposure to heat stress will be allowed, if the method is in accordance with recognized industrial hygiene practices and equally protects the health and safety of workers
4. If physiological monitoring is used as part of an alternative method of assessing exposure to heat stress, it must be conducted under the supervision of a person who is qualified, because of knowledge, training and experience, to recognize and assess heat strain and heat-related illness resulting from hot work conditions.
5. Engineering controls must be used to maintain a worker’s heat exposure within the heat stress exposure limits, except if: 

• The workplace is outdoors
• The workplace is indoors and engineering controls are sufficient to protect workers in usual thermal conditions, but there is a temporarily high level of heat unrelated to the workplace or work process being performed, such as a hot spell or heat wave, such that it is not reasonably practicable to protect workers through the use of engineering controls alone, or 
• The workplace is indoors and the usual thermal conditions related to the workplace or work processes are such that it is not reasonably practicable to control some or all of the sources of heat through the use of engineering controls alone.

6. Any additional measures and procedures implemented, beyond engineering controls to control heat exposures must: 

• be developed in consultation with the joint health and safety committee or health and safety representative, if any; 
• include administrative controls, such as reducing the amount of time a worker spends in exposure to heat through implementation of a work-rest cycle, adjusting the start of the work day, or provision of more frequent breaks; 
• include the use of personal protective equipment, such as anti-radiant heat or reflective clothing and, in the case of outdoor work in exposure to solar radiation, the use of adequate head protection, clothing and sunscreen, and; 
• be in writing

7. Employers must provide cool, potable drinking water or another adequate hydrating fluid, close to the work areas, for the use of workers in hot conditions.

8. Workers must be provided the following information and instruction where the thermal conditions in a workplace or related to a specific work process will pose or are likely to pose a hazard to the worker’s health or safety:

• the measures and procedures to be implemented to protect the worker, including the engineering controls to be implemented
• the importance of staying hydrated and of taking breaks and all rest periods identified in the work-rest cycle set out in the measures and procedures
• the early signs and symptoms of heat strain and heat-related illnesses and the precautions to be taken to avoid illness or injury
• steps the worker should immediately take if they suspect they are experiencing heat strain or heat-related illness

9. In areas where a heat warning has been issued by Environment and Climate Change Canada, employers of workers working outdoors or workers who face an increased risk of developing a heat-related illness as a result of a change in their usual thermal workplace conditions must advise them of the heat warning, the importance of staying hydrated and taking breaks and all rest periods identified in the work-rest cycle set out in the employer’s measures and procedures.

Stakeholders can post their comments on the proposed legislation through the via email here until Sept. 1, 2023.

The traditional nine-to-five working hours may need to begin a little earlier than usual as the world continues to heat up amid a changing climate, according to experts.