European hospitals are failing to cope with extreme heat, with critical systems collapsing and patients put at risk as temperatures soar. In England, several NHS trusts have declared critical incidents after cooling failures shut down MRI scanners, radiotherapy machines and electronic patient records. Portsmouth Hospitals University NHS Trust and Norfolk and Norwich University Hospitals NHS Foundation Trust were among those forced to cancel hundreds of outpatient appointments when chiller units failed. The pattern is continental: during June’s record-breaking heatwave, France raised its health system to the highest level of emergency mobilisation, while hospitals in Italy, Spain and Germany reported surging admissions and cooling systems that could not keep pace. Across Europe, health professionals are working sleep-deprived in sweltering, un-air-conditioned wards, with consequences for both staff wellbeing and the safety of care.
The scale of the crisis is matched only by the depth of the unpreparedness. A 2024 survey of more than 1,000 UK healthcare professionals, cited by Health Care Without Harm Europe and the European Federation of Nurses Associations (EFN), found that over 90% said heat stress impaired their performance and nearly three‑quarters called existing protections inadequate. Separate research by the Doctors’ Association UK (DAUK) reported that more than 94% of respondents had no or only partial working air conditioning in their main clinical area, with 95% describing their workplace as uncomfortably warm, very hot, or dangerously hot. More than two‑thirds of staff surveyed said the heat had affected patient care or safety. Geriatric wards have recorded temperatures as high as 35°C, with staff and patients enduring “awful conditions”. Patients – particularly older people – are presenting with dehydration and heat‑related illnesses, driving increased admissions and A&E attendances.
The financial toll is already severe. A study estimated that extreme heat and cold together account for roughly 3% of NHS England’s primary and secondary care costs – around £3 billion annually. In 2022, heatwaves caused cooling system failures at data centres serving two major London hospitals, leading to significant treatment delays and costing the NHS £1.5 million. Yet the underlying problem is structural. Many hospital buildings were not designed for the temperatures now being experienced, and existing cooling systems are insufficient for prolonged hot periods. The Climate Change Committee has warned that the UK’s infrastructure is “built for a climate that no longer exists” and requires urgent improvement.
The NHS has made ambitious net‑zero commitments – becoming the first healthcare system globally to set such targets in October 2020, with a goal of net‑zero direct emissions by 2040 and influenced emissions by 2045. It has achieved a 14% reduction in its carbon footprint since 2019‑20, and over 68% since 1990. But adaptation has lagged behind emissions reduction. The Health and Care Act 2022 introduced duties for trusts and integrated care boards to consider climate change in their operations, and the fourth Health and Climate Adaptation Report supports the NHS in building a climate‑smart, resilient service. Nonetheless, Nadine Henderson, principal economist at the Office of Health Economics, warned that “there is an overwhelming risk that much‑needed decarbonisation and adaptation activities are deprioritised amid the competing reforms and scant resources faced by the NHS”. She noted that the NHS 10‑year plan – which sets out a vision for transforming healthcare delivery in England – has no specific proposals that explicitly address how to decrease NHS carbon emissions or how it interacts with the climate adaptation report. “The intersection of climate resilience and health has to be a core component of public health strategy,” she said. “It can’t be a peripheral concern.”
Across Europe the picture is no better. Nearly half of hospitals in European cities sit in urban heat island hotspots, according to data referenced by campaigners. The World Health Organization has launched updated guidance on heat–health action plans, and the European Environment Agency (EEA) has identified health as one of five priority areas in its assessment of climate risks, describing the level of risk from heat in the latter half of the century as “catastrophic”. The WHO estimates that over 200,000 lives have been lost across 32 European countries due to heat in the past four years, with most deaths preventable. The Lancet Countdown on Climate Change and Health 2026 Europe Report warns of rising heat‑related deaths, with an estimated 62,000 in 2024 alone.
Health professionals across the continent are now demanding a shift from reaction to prevention. The European Federation of Nurses Associations has endorsed Health Care Without Harm Europe’s #HandleTheHeat campaign, which calls for climate‑ready hospitals and stronger workforce protections. An open letter to the European Commission, signed by healthcare workers across Europe, urges the development of an EU climate and health strategy, support for low‑carbon, climate‑resilient healthcare facilities, and mandatory adaptation measures. As Mark Wilson, executive director of Health Care Without Harm Europe, and Dr Paul De Raeve, secretary general of the EFN, put it: “Extreme heat is not an exceptional event and Europe’s response to it should stop being exceptional too. Protecting patients and those who care for them must become a core part of climate adaptation policy, not an afterthought.”