Workers in the UK could be permitted to stop work during heatwaves under new health and safety plans being drawn up by the Health and Safety Executive (HSE). The proposals come as the country experiences its fourth heatwave of the summer, with the Met Office forecasting that UK summers could soon bring temperatures as high as 45°C.
The HSE is revising its Approved Code of Practice for workplace temperatures — first published in 1992 — to reflect the growing risks posed by climate change. While the regulator is not expected to introduce a legal maximum temperature, it will recommend that employers carry out heat stress assessments when conditions become excessively hot. This would require businesses to take steps such as increasing rest breaks, improving access to shade and water and adjusting shift times to avoid the hottest part of the day.
Labour has already pledged to “modernise” workplace safety rules to reflect extreme weather patterns, with detailed proposals expected in the coming months. Speaking in the House of Lords, Labour minister Baroness Jones of Whitchurch said last month: “We recognise that workplace temperatures are changing, especially as the climate changes,” and that the government was committed to making workplaces safe “in the modern world”.
Unions demand a legal maximum
Trade unions, including the Trades Union Congress (TUC), Unite and GMB, are pushing for stricter rules, calling for a maximum legal working temperature of 27°C for manual jobs and 30°C for indoor office work. Although this is not currently part of the HSE’s plan, unions have raised the issue directly with ministers and are urging the regulator to go further.
“Ultimately, there needs to be a legal maximum working temperature, in the same way we have a legal minimum working temperature,” said Lynsey Mann, health and safety officer at GMB. “As the climate changes, it is vital that health and safety law is updated in line with the serious challenges this presents for workers.”
Paul Nowak, general secretary of the TUC, added: “With heatwaves becoming more common, we need to adapt. We need new laws on maximum working temperatures, improvements to workplaces to keep them cool, and climate action to reduce global heating.”
Other European countries have already adopted such measures. Greece has mandated afternoon breaks for outdoor workers during extreme heat, while Spain, Italy and Germany also enforce workplace temperature limits.
No legal maximum — yet
Under current UK law, employers have a duty to provide a “reasonable” temperature in the workplace, as outlined in the Health and Safety at Work Act 1974 and Workplace (Health, Safety and Welfare) Regulations 1992. While there is a suggested minimum temperature of 13°C for strenuous work and 16°C for sedentary roles, no legal maximum is set.
The HSE says it will not propose a legal cut-off point for temperature but will instead require employers to assess risk and take action. This includes recognising heat as a hazard, consulting with workers or their representatives, and taking reasonable steps to mitigate harm.
A spokesperson said: “The risks to workers from extreme heat must be properly assessed. Practical steps can include providing adequate ventilation and shade, and allowing enough breaks for workers to cool down.”
Many local authorities and private contractors are already adapting to high temperatures. Waste collection firm Biffa, which operates in 30 local authority areas, has shifted its bin collection start times to 5am during heatwaves to reduce staff exposure. The company also provides lightweight uniforms, sun protection and access to water throughout the day.
“Climate change has a significant impact on weather patterns,” said Steve Cole, managing director of Biffa Municipal. “A key priority for us is ensuring front-line workers are protected and are at minimal risk.”
Business groups raise concerns
Some industry groups have expressed concern about the potential impact of new rules on productivity. Craig Beaumont, executive director of the Federation of Small Businesses, said: “Employers already have a legal duty to ensure the temperature in their workplace is reasonable. This approach appears to work, so any new regulations must set out why they would be an improvement.”
Mike Wood, shadow Cabinet Office minister, added: “Giving public sector workers an excuse to clock off the moment the mercury rises will be a recipe for productivity to plummet even further.”
The government has said it has no current plans to introduce a maximum workplace temperature in law, but will consider HSE recommendations once they are formally submitted.
Expert view: Heat harms more than we think
Dr Chris Tyler, a Reader in Environmental Physiology at the University of Roehampton, warned that even moderate indoor heat can affect performance and wellbeing long before it becomes visibly dangerous.
“A lot of people assume that if no one’s collapsing, there’s no problem, but that’s just not the case,” he said. “Heat doesn’t have to be extreme to start affecting people’s wellbeing and productivity. Even relatively small increases in indoor temperature can impair wellbeing, cognitive function and productivity. When an individual is exposed to hot conditions, we see things like fatigue, poor sleep, dips in concentration and mood changes, but these symptoms often go unnoticed or unreported.
Dr Tyler added that the solution was “not to focus on just one thing, like hydration. Managing heat properly means using a layered approach: helping people acclimatise gradually, putting in effective cooling strategies, encouraging structured hydration and monitoring for early signs of heat strain”.
He recommends employers adopt practical, low-cost strategies to help staff stay cool and reduce heat-related performance drops. This includes:
- Localised cooling zones – Install desk fans or under-desk cooling mats targeting the lower legs and feet, which are key areas for heat exchange
- Personal cooling packs – Use neck wraps, cooling wristbands or chilled towels applied to pulse points like the neck, wrists and groin
- Staggered cooling breaks – Short, frequent breaks in cool areas are more effective than longer, infrequent pauses
- Wearable tech – Devices such as smartwatches or patches may help monitor heart rate for signs of overheating. Some claim to track core temperature, though they may be unreliable
- Supervisor check-ins – Line managers should regularly ask how staff are coping during heatwaves, rather than waiting for complaints
- Temperature control – Air conditioning is more effective than fans, though more energy intensive. Both have a place in managing office climate
