Heat Stress in the World of Work: Canadian Collective Bargaining and Environmental Governance

As climate change accelerates, extreme heat is becoming a critical occupational hazard across Canada. Yet worker protections remain fragmented, reactive, and highly uneven across sectors and provinces. This article offers a socio-legal analysis of how heat stress is governed through regulation, collective bargaining, and emerging private governance mechanisms. Drawing on a review of federal and provincial occupational health and safety statutes, a content analysis of over 50,000 collective bargaining agreements, and an assessment of ESG disclosures, Global Framework Agreements, and Worker-Driven Social Responsibility models, the study maps Canada’s evolving approach to heat protection. It finds that CBA coverage remains minimal and concentrated in a small number of unionized manufacturing settings, particularly in Ontario. While Ontario demonstrates the potential for a more coordinated model—especially if proposed legislation complements negotiated protections—the province’s current framework remains limited in scope and sectoral reach. The article argues that effective heat governance will require hybrid coordination across statutory, contractual, and voluntary domains, supported by technology, institutional linkages, and adaptive worker voice. It concludes by outlining an integrated framework for climate-era labour protection grounded in enforceable rights, dynamic bargaining, and transparent corporate accountability.