Climate change and workplace heat stress: technical report and guidance

This report draws on five decades of research and evidence, highlighting that the health and productivity of workers are severely impacted by rising temperatures. The World Meteorological Organization (WMO) reports that 2024 was the hottest year on record. Daytime temperatures of more than 40°C and even above 50°C are becoming increasingly common, a clear indication that immediate action is needed to address the worsening impact of heat stress on workers worldwide.

The key findings of this report, include:

• The frequency and intensity of extreme heat events have risen sharply, increasing risks for both outdoor and indoor workers.
• Worker productivity drops by 2-3% for every degree above 20°C.
• Health risks include heatstroke, dehydration, kidney dysfunction, and neurological disorders, all of which hinder long-term health and economic security.
• Approximately half the global population suffers adverse consequences of high temperatures.