By Alanna Orpen, Senior Media and Communications Officer, The Physiological Society
The consequences of heat are far reaching and worsening over time. Advocates for worker protection during extreme heat discussed the hazards and solutions at the Global Climate and Health Summit (London, July 2025)
“Do I protect my health or my income?” said Professor Elizabeth Robinson (London School of Economics and Political Science (LSE) raising the concern of gig workers, including construction workers, food delivery drivers and cyclists, who weigh the decision when waking up on a hot day, temperatures soaring over 30°C. This is the scenario UK workers face during a heatwave. Especially challenging for the 1.5% of the workforce, which is just under half a million people, who are without formal contacts.
Professor Robinson addressed this in her opening of the heat resilience session, ‘Engaging employers and policymakers – the business and regulatory case for heat protections’ on Day 1 of the Global Climate and Health Summit. “If we don’t take heat seriously, how does the economy keep functioning?” she asked, explaining that the UK infrastructure is ill equipped to cope with heatwaves, with evidence showing that workers’ health and productivity could be compromised. She was joined on stage by an expert panel to deliberate practical solutions to the economic implications of heat.
“Climate change is affecting the human right to safe and healthy working conditions,” stated Dr Shouro Dasgupta (Euro-Mediterranean Center on Climate Change (CMCC). During his presentation, Dr Dasgupta talked about the detriments of heat stress on the UK labour force, “more than 100 million working hours could be lost.” The startlingly stat was reported in the study by Dr Dasgupta and Professor Robinson (lead author), which surveyed over 2,000 people in the labour force immediately after a period of extreme heat, with recorded temperatures above 30°C, during the UK summer of 2024.
Their study, published in 2024, was the first to provide quantitative data on the negative impact of heat on worker health in the UK, and the extent in which the labour force can adapt their working patterns. It is nationally representative of the UK workforce, covering a variety of contracts, exposure levels across sectors and across the country. 1.3% of those surveyed were working in high-exposure sectors, including agriculture, forestry and fishing, mining and quarrying. 7.2% worked in manufacturing and 86.1% in the services sector.
Harmed by the heat
A third of the workers surveyed were affected by the heat, reporting symptoms of heat stress or heat exhaustion, such as headaches or dizziness. Less than half of those surveyed had access to air conditioning or other cooling system, and just over a third said that their employer had not made any adjustments to help them adapt to the heat.
There was a clear link between a 1°C increase in temperature anomaly and hours worked. “We found a 10% decrease in workers’ productivity and hours during a period of extreme heat,” said Dr Dasgupta, “this is compared to 4% decrease when adaptations were put in place, such as heat alerts.”
“Our findings improve our understanding of the economic and health implications of heat on the labour force, which can assist policy makers in designing more efficient and equitable policies that have the potential to protect both worker health and employer profits and so contribute to reducing the negative impacts of increasing heat on GDP,” said Professor Robinson.
Unlike many European countries, the UK does not have a statutory maximum working temperature. Calls for heat thresholds have been made to government. While it considers introducing the regulation, workers are vulnerable to the harm of heat stress during hot summers and heatwaves, which are expected to be more frequent and temperatures more severe due to climate change. “Physiological heat thresholds are a controversial topic,” admitted Dr Dasgupta at the Summit. Keen to see thresholds as part of the solution, he suggested, “the regulation could be rolled out sector by sector, rather than having a uniform rule where every sector had to abide by one temperature.”
Adapting to protect health and reduce the heat-related burden
Adaptation can be a win-win for employer and employee, where simple adaptation methods can be highly effective for occupational health. Employers protect the health of their workforce without losing productivity, and workers feel empowered too. This includes workers adapting their patterns by shift changes (starting work earlier or later, or finishing earlier or later), working shorter hours, reducing effort, or taking more frequent breaks.
Professor Robinson adds that “many employers have implemented adaptations, such as investing in air conditioning, or increasing outdoor workers’ access to shade and hydration and frequency of rest breaks. But adaptation is still insufficient, and the frequency and intensity of heatwaves is only going to get worse as human-caused climate chance continues to worsen, highlighting the importance of both mitigation and adaptation.”
Unfortunately, not all workers are equally empowered to make adaptation decisions. Gig workers, those working on an hourly wage or paid by commission, are particularly vulnerable because of their livelihoods. The study found that they were more likely to reduce their working hours during a heat episode, showing that job security and contract type matters, and can limit the flexibility compared to those paid a salary.
Worker empowerment
UK workers are feeling the heat, so how can we protect people and workers? During the Summit session, Professor Robinson asked the panel what solutions they would like to see. Mandatory climate risk assessments by organisations was one contribution. Another suggestion was that regulation should be fit for the modern era, and to see accountability from worker to employer, with workers being able to take ownership of their own health. The panel also turned our attention to the home. To improve UK infrastructure, they advised that healthy and sustainable homes should be built for the heat. “We’re running towards a positive vision,” was an encouraging thought, where a panellist spoke of a future where nature and people are aligned for health, wellbeing and quality of life.
A recurring theme during the Summit session was that solutions need to strike a balance between empowerment and regulation to reduce the health risks. Adaptation strategies are part of the solution to reduce the heat-related burden and negative impact of climate change for the UK labour force. “Sensible adaptations can improve health, improve productivity, and the productivity improvement could cover the cost of the adaptation strategies,” said Professor Robinson.
Professor Robinson and Dr Dasgupta were members of the Summit Steering Group. They would like to provide further evidence for regulations to protect the workforce, interested in collecting more data to track the long-term impact on how workers are affected by heat and test efficacy of adaptation strategies.
Read their full study ‘Improving the resilience of the UK labour force in a 1.5°C world’.
