In A Flash

Ontario Contemplates, Seeks Input Into, OHSA Outdoor Air Quality and Heat Stress Requirements

The Ontario Ministry of Labour, Immigration, Training and Skills Development  (“MLITSD”) announced last week it is seeking prompt comments and feedback on two Occupational Health and Safety proposals, one in relation to air quality and the other relating to heat stress.  

Air Quality Proposal

Feedback from employers and others is being sought on whether poor outdoor air quality is an issue for Ontario workplaces, and whether the Ontario Occupational Health and Safety Act (“OHSA”) and/or its Regulations may need to be changed. As noted in the proposal, the OHSA and its regulations do not specifically address poor outdoor air quality however under the OHSA, employers have a general duty to take every precaution reasonable in the circumstances for the protection of a worker. This includes, they state, protecting workers from the hazards associated with poor outdoor air quality that could pose a risk to workers working outdoors.

There are a series of questions posed to the public including but not limited to how working outdoors in poor air quality impacts workers’ ability to perform duties, what measures are in place for worker protection and how the government can support workers during times of poor outdoor air quality. There is no apparent proposal to attempt to revise any Regulation, or draft specific new Regulations on the subject at this time.

The full proposal can be found here.

If you are interested in providing feedback on the air quality proposal, you can do so here until September 18, 2023. (Update: The deadline for comments has been extended from September 1, 2023) 

Heat Stress Regulation Proposal

The Ontario MLITSD is however proposing to introduce a new stand-alone Heat Stress Regulation under the OHSA, with specific requirements which would apply to all workplaces to which the OHSA currently applies. Commenting on the current OHSA employer general duty to take every precaution reasonable in the circumstances for the protection of a worker, the Ministry’s proposal states its position that this duty includes protecting workers from “hazardous thermal conditions that may lead to heat-related illnesses”. The proposal is lengthy. As a broad overview, a new proposed Regulation being considered, and upon which input is currently sought, would seek to:

  • Introduce heat stress exposure limits based on already recognized American Conference of Governmental Industrial Hygienists (ACGIH) methods;
  • 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 ACGIH “hierarchy of controls”;
  • Require employers to provide worker information and instruction on recognizing the signs and symptoms of heat-related illnesses and the measures to protect themselves; and
  • Require employers to take all measures reasonably necessary to protect workers from exposure from “hazardous thermal conditions that may lead to heat-related illnesses”, or a worker’s core temperature from exceeding 38 degrees C (100 degrees F).

In addition to the proposal, the MLITSD has also provided consultation questions. This includes but is not limited to whether your workplace potentially exposes workers to thermal conditions that may lead to a heat-related illness, what method(s) are used to monitor and assess worker exposure, what measures you think are most effective at protecting workers and how you think the MLITSD can best help employers to implement the proposed new requirements. 

The full proposal can be found here. Employers interested in providing feedback on the heat stress regulation proposal, can do so here until September 18, 2023. (Update: The deadline for comments has been extended from September 1, 2023) 

Many sources of information, including from several Ontario Safe Workplace Associations as well as the Canadian Centre for Occupational Health and Safety (“CCOHS”) provide comprehensive information and guidance to employers and others on best practices for management and prevention of heat stress. The CCOHS resource can be accessed here. We would note that no existing resource appears to include or focus on any means to measure whether a worker’s core body temperature exceeds a particular limit. Any employer wishing to comment on the complexities of this proposed new requirement ought to do so.

If you have any questions about this topic or any other questions relating to workplace law, please do not hesitate to contact a Mathews Dinsdale lawyer.

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