WHO, WMO warn of rising worker risks from extreme heat

The World Health Organization (WHO) and the World Meteorological Organization (WMO) have released a joint report addressing the escalating threat of extreme heat on global workforces.

As climate change intensifies heatwaves, millions of workers in agriculture, construction, and fisheries are already experiencing severe health consequences.

Children, older adults, and low-income populations in developing nations face additional risks from rising temperatures.

“Heat stress is already harming the health and livelihoods of billions of workers, especially in the most vulnerable communities,” said Dr. Jeremy Farrar, WHO Assistant Director-General, Health Promotion, Disease Prevention and Care.

“This new guidance offers practical, evidence-based solutions to protect lives, reduce inequality, and build more resilient workforces in a warming world,” he added.

The report, Climate change and workplace heat stress, draws on five decades of research showing significant declines in health and productivity due to rising heat.

WMO confirmed that 2024 was the hottest year ever recorded, with daytime temperatures above 40°C and even 50°C becoming increasingly frequent.

“Occupational heat stress has become a global societal challenge, which is no longer confined to countries located close to the equator – as highlighted by the recent heatwave in Europe,” said WMO Deputy Secretary-General Ko Barrett.

“Protection of workers from extreme heat is not just a health imperative but an economic necessity,” Barrett said.

The report’s findings show that worker productivity drops by 2–3% for every degree above 20°C.

Documented health impacts include heatstroke, dehydration, kidney dysfunction, and neurological disorders that jeopardize long-term health and economic security.

An estimated half of the global population suffers negative effects from high heat exposure.

The report recommends that governments, employers, and health authorities implement occupational heat action plans tailored to specific regions and industries.

These plans should include policies informed by local weather patterns, job types, and worker vulnerabilities.

Special protections are advised for middle-aged and older workers, people with chronic conditions, and those with lower physical fitness.

The guidance also calls for raising awareness among first responders, health professionals, employers, and workers to correctly identify and treat heat stress symptoms.

It urges stakeholder engagement, including workers, trade unions, health experts, and local authorities, in designing strategies that are practical, affordable, and sustainable.

Innovation, new technologies, and further research are encouraged to safeguard health while preserving productivity.

The report builds on International Labour Organization (ILO) findings that more than 2.4 billion workers face excessive heat, resulting in over 22.85 million occupational injuries annually.

“This report represents a critical milestone in our collective response to the growing threat of extreme heat in the world of work,” said Joaquim Pintado Nunes, ILO’s Chief of Occupational Safety and Health and the Working Environment.

“Aligned with the ILO’s mandate to promote safe and healthy working environments as a fundamental right, it offers robust, evidence-based guidance to help governments, employers and workers confront the escalating risks of climate change,” Nunes said.

“Together with WHO and WMO, we call for urgent, coordinated action to safeguard the health, safety and dignity of the more than 2.4 billion workers exposed to excessive heat worldwide,” he added.

The guidance aligns with the United Nations Sustainable Development Goals by linking worker health to poverty reduction and sustainable growth.

Immediate implementation of protective policies is described as critical to saving lives, livelihoods, and economies from worsening climate-driven heat stress.