This was according to a new report jointly released in late August by the World Health Organization (WHO) and the World Meteorological Organization (WMO).
The report, titled ‘Climate change and workplace heat stress: technical report and guidance’, highlights “the growing global health challenges posed by extreme heat on workers” and offers guidance on dealing with this threat.
“The frequency and intensity of extreme heat events have risen sharply, increasing risks for both outdoor and indoor workers,” the agencies said in what they described as a much-needed major update of a report and guidance last published in 1969.
High temperatures and health risks
According to a Reuters report, it was estimated that the harmful consequences of high temperatures were already being experienced by about half the world’s population.
The WHO and WMO report says these health risks include heatstroke, dehydration, kidney dysfunction, and neurological disorders, “all of which hinder long-term health and economic security”.
Those particularly at risk were manual workers in sectors such as agriculture, construction, and fishing, along with vulnerable population groups, including children and older adults in developing countries.
“Protection of workers from extreme heat is not just a health imperative but an economic necessity,” WMO Deputy Secretary-General Ko Barrett said at the launch of the report.
Therefore, the agencies were calling on public health experts to develop action plans to deal with extreme heat, in co-operation with employers, worker unions, and workers, which were tailored to specific regions and industries, the report says.
Although the option existed to introduce maximum legal working temperatures, for example, as called for by unions in some countries, the report said this would “likely differ globally, depending on the context”.
Higher temperatures, lower productivity
It says it was found that for every degree above 20°C, workers’ productivity declined by between 2% and 3%.
“These effects of climate change are primarily felt by those who work outdoors, making it difficult to perform their work adequately and leading to increased rates of absenteeism.
“Potential disruptions in productivity affect millions of people in heat-vulnerable sectors such as agriculture and construction but also undermine primary production and trade, while creating significant spillover effects on the economy,” the report states.
Other recommendations include that in industries with limited access to clean water, such as agriculture, workers should be provided with water bottles and be informed about hydration and the need for electrolytes in fluid and food.
“Access to toilet facilities is key, as workers may not hydrate if they lack access [to these].”
The reported also urges improved education of health workers and first responders, because heat stress is often misdiagnosed.
A recent finding by the International Labour Organization indicated that globally, in excess of 2,4 billion workers were being exposed to excessive heat, which were resulting in over 22,85 million occupational injuries every year.
According to the WMO, 2024 was the hottest year on record.
“Daytime temperatures of more than 40°C and even above 50°C were becoming increasingly common, a clear indication that immediate action is needed to address the worsening impact of heat stress on workers worldwide.
“No one should have to risk kidney failure or collapse just to earn a living,” Rüdiger Krech, interim director for environment, climate change, and health at the WHO, said at a media conference.
Barrett added: “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.”
The report’s guidance lays out a clear path for governments, employers, and health authorities to mitigate the growing risks of extreme heat on working populations.
Dr Jeremy Farrar, assistant director-general for health promotion, disease prevention, and care at the WHO said: “This new guidance offers practical, evidence-based solutions to protect lives, reduce inequality, and build more resilient workforces in a warming world.”
The technical guidance drew on five decades of research and evidence, which confirmed how the health and productivity of workers were being severely affected by rising temperatures, according to the report.
