The World Health Organization (WHO) and World Meteorological Organization (WMO) have highlighted alarming global health threats from extreme heat stress affecting workers. As climate change intensifies, heatwaves are becoming more frequent and severe, placing millions of outdoor and indoor workers at risk.
Manual laborers in agriculture, construction, and fisheries face the most direct exposure, while vulnerable populations in developing countries suffer heightened health consequences.
Heat Stress Already Impacting Worker Health
“Heat stress is already harming the health and livelihoods of billions of workers, especially in the most vulnerable communities,” said Dr. Jeremy Farrar, WHO.
The new joint report, Climate Change and Workplace Heat Stress, combines five decades of research on temperature-related occupational hazards.
With daytime temperatures exceeding 40°C and sometimes 50°C, the report warns that extreme heat is no longer a regional concern but a global workforce challenge.
WMO’s recent data confirm 2024 as the hottest year on record, underlining the urgency of immediate action to safeguard workers worldwide.
Key Findings of the Report
The report highlights several critical issues surrounding extreme heat and its impact on worker health and productivity:
- The frequency and intensity of extreme heat events have risen sharply, increasing risks for both indoor and outdoor workers.
- Worker productivity declines by 2–3% for every degree Celsius above 20°C, impacting economic outcomes globally.
- Heat-related health risks include heatstroke, dehydration, kidney dysfunction, and neurological disorders, threatening long-term health.
- Approximately half of the global population experiences negative effects from high temperatures, emphasizing the widespread nature of the challenge.
Vulnerable Populations Face Highest Risks
Workers most at risk include older adults, individuals with chronic health conditions, and those performing physically demanding tasks in high-heat environments.
Low-income populations in developing nations and children are particularly susceptible due to limited access to cooling infrastructure and healthcare.
The report underscores that protecting vulnerable populations is not only a health imperative but an economic necessity.
Recommended Actions to Protect Workers
The WHO and WMO guidance outlines clear, evidence-based measures for governments, employers, and health authorities to mitigate extreme heat risks:
- Develop occupational heat-health policies tailored to local weather, specific jobs, and worker vulnerabilities.
- Focus on vulnerable populations, including older workers, people with chronic illnesses, and individuals with lower physical fitness.
- Educate first responders, healthcare professionals, employers, and workers to identify and treat heat stress early.
- Engage stakeholders, including trade unions, local authorities, and health experts, to co-create locally relevant heat-health strategies.
- Design practical, affordable, and environmentally sustainable solutions that can be implemented at scale.
- Adopt innovative technologies to safeguard worker health while maintaining productivity.
- Support research and evaluation to strengthen occupational heat-health interventions globally.
Economic and Productivity Impacts
Occupational heat stress has measurable economic consequences, including reduced productivity and increased workplace injuries.
Productivity can drop by up to 3% for every degree above 20°C, affecting both industrial and agricultural sectors worldwide.
The report calls for policies that protect worker health while maintaining economic output, reinforcing that heat stress management benefits societies broadly.
Collaboration with ILO and Other Agencies
The guidance complements recent International Labour Organization (ILO) findings, which indicate over 2.4 billion workers face excessive heat exposure globally.
These conditions result in more than 22.85 million occupational injuries annually, highlighting the need for coordinated global action. Joaquim Pintado Nunes, ILO Chief of Occupational Safety and Health, emphasized that protecting workers from heat is a fundamental right and a global economic priority.
Implementation Strategies for Governments and Employers
Governments and employers can adopt practical strategies to reduce heat stress risks:
- Establish heat alert systems and heat-health advisories tailored to local conditions.
- Implement mandatory rest periods and shaded or cooled work areas during peak temperatures.
- Promote hydration and access to drinking water across all workplaces.
- Ensure heat-health plans include monitoring, early warning, and emergency response protocols.
- Train workers to recognize early symptoms of heat stress to prevent severe health outcomes.
Climate Adaptation and Sustainable Workforce Planning
Addressing heat stress aligns with United Nations Sustainable Development Goals, including decent work, health, and climate action. Integrating occupational heat-health measures into climate adaptation plans strengthens workforce resilience while promoting sustainable economic growth.
Innovative solutions, including wearable monitoring devices and mobile health platforms, can support real-time worker safety in extreme temperatures.
Call to Action: Protecting Lives and Livelihoods
WHO and WMO call for urgent, coordinated action to safeguard worker health from the escalating threat of heatwaves.
Prioritizing occupational heat-health policies ensures workers’ dignity, safety, and long-term economic stability.
Immediate implementation of evidence-based interventions is crucial to reduce injury, illness, and productivity loss caused by extreme heat worldwide.
The guidance empowers policymakers, employers, and public health officials to develop practical, scalable, and locally relevant solutions for climate-induced heat risks.
A Global Imperative for Workplace Safety
As climate change drives rising temperatures, occupational heat stress is an increasingly urgent global challenge.
WHO and WMO’s report provides a roadmap for protecting the health, safety, and productivity of billions of workers.
From implementing heat-health policies to raising awareness and leveraging technology, proactive action can save lives and safeguard livelihoods.
Coordinated efforts across governments, employers, unions, and health organizations are essential to build resilient workforces capable of thriving in a warming world.
