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Ontario Government Initiates Public Consultations on Potential OHSA Amendments Relating to Outdoor Air Quality and Heat Stress


Canada is now more than halfway through the worst wildfire season this country has ever seen. Every province and territory has been impacted by this year’s wildfires, whether directly or through resultant air quality issues, with Alberta, Ontario, Nova Scotia, Quebec, and most recently, British Columbia and the Northwest Territories having been particularly hard-hit. Climate scientists have warned that rising global temperatures mean that this year’s unprecedented wildfire season is unfortunately a harbinger of what we can expect in years to come.

In response to rising concerns around air quality issues in outdoor workplaces due to pollutant emissions as well as workplace heat stress, the Ontario Ministry of Labour, Immigration, Training and Skills Development (MLITSD) has announced that it is seeking public input on two occupational health and safety-related legislative proposals:

  1. Proposed Air Quality Regulation: Although Ontario’s Occupational Health and Safety Act (OHSA) and its regulations do not currently address poor outdoor air quality, employers in Ontario have a general duty to take every precaution reasonable in the circumstances to protect workers, including those who work outdoors and may be exposed to hazards associated with poor outdoor air quality. Accordingly, MLITSD is conducting a Regulatory Impact Analysis to determine whether poor outdoor air quality is an issue of concern in Ontario workplaces, and whether the OHSA and/or its regulations need to be amended to address such concerns. Employers and the public are invited to provide comments and feedback pertaining to the anticipated costs and benefits of such proposed amendments via email here.
  2. Proposed Heat Stress Regulation: As we previously reported here, heat stress is a significant cause of occupational illnesses. Our changing climate and rising global temperatures mean that extreme heat events will only become more common in the foreseeable future. An employer’s general duty to take all reasonable precautions to protect workers includes, according to MLITSD, “protecting workers from hazardous thermal conditions that may lead to heat-related illnesses.” Accordingly, MLITSD is proposing to introduce a stand-alone heat stress regulation under the OHSA setting out specific requirements that would apply to all workplaces subject to the OHSA. The proposal on which MLITSD is seeking feedback through a Regulatory Impact Analysis is lengthy, but includes the following:
    • requiring employers 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;
    • requiring compliance with heat stress exposure limits for light to very heavy workloads, in accordance with methods used to determine heat exposures;
    • requiring employers to provide cool, potable drinking water or another adequate hydrating fluid close to work areas, for the use of workers in hot conditions; and
    • requiring employers to provide workers with information and instruction where temperatures 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.

Feedback on the heat stress-related regulatory proposal can be provided here.

The Cassels Employment & Labour Group will be continuing to monitor developments with respect to these potential legislative amendments and will provide further updates as they become available.

This publication is a general summary of the law. It does not replace legal advice tailored to your specific circumstances.

For more information, please contact the author of this article or any member of our Employment & Labour Group.