As temperatures in parts of the UK are forecast to approach 40°C this week, a glaring gap in the country’s legislative framework is exposed: neither workplaces nor schools are subject to a legal maximum temperature limit. While the Met Office has issued a rare red extreme heat alert for central England, southern England and Wales, and the UK Health Security Agency has published red and amber heat-health alerts warning of a risk to life, the legal protections for employees and pupils remain conspicuously absent.
Workplace heat: duties without a limit
There is no specific law in the UK that sets a maximum temperature for workplaces. Lucy Needham, an employment solicitor at Lime Solicitors, told The i Paper that there is no legal threshold at which workers can simply down tools and leave. “There’s not a legal maximum workplace temperature where we can say, if it hits X degrees, then we can down tools and leave. But that doesn’t mean that employers sort of have no duty,” she said. The absence of a single figure reflects the diversity of working environments, she explained: “Somebody who works in a bakery or somewhere where there’s food being prepared would work in a hotter environment than someone, say, in an office or a school.”
Nevertheless, heat is officially classed as a hazard. The Health and Safety Executive (HSE), the UK’s independent workplace regulator, states: “All workers are entitled to an environment where risks to their health and safety are properly controlled. Heat is classed as a hazard and comes with legal obligations like any other hazard.” Under that duty, employers must carry out risk assessments to identify and manage heat-related risks. While the HSE provides guidance on a reasonable minimum indoor temperature — 16°C for sedentary work and 13°C for physically demanding work — it offers no specific maximum figure. What makes an upper limit so difficult to fix, according to Professor Simon Hodder, an expert in environmental ergonomics at Loughborough University, is the interplay of temperature and humidity. “A high temperature with low humidity feels a lot better than a high temperature and high humidity,” he noted.
Instead of a simple temperature cap, the HSE advises employers to implement a range of practical measures. Ahead of this week’s heatwave, it recommended providing adequate ventilation and shade, giving workers free drinking water, introducing flexible work patterns and breaks, and relaxing formal dress codes. For outdoor staff, the HSE advised rescheduling work to cooler times of the day and ensuring shade and water are available. Workers should use fans, take regular breaks, stay out of direct sunlight and, if performing very physically demanding jobs in hot conditions, drink 250ml of water every 15 minutes. Other steps include using blinds or reflective film to block direct sunlight, moving workstations away from heat sources, turning off non-essential electrical equipment to reduce radiated heat, and sharing information about the symptoms of heat stress.
Because there is no legal maximum, employees cannot demand time off or the right to work from home purely because of the heat, though they can discuss it with their employer. But the employer’s overarching duty of care is a legal requirement. “They do have a duty of care towards their employees, and that’s a legal requirement where they need to be looking at the procedures that they have in place for extreme weather,” Needham said. Failure to do so carries consequences. She added that if employers do not give adequate protection for outdoor employees against sunburn, heatstroke and dehydration, they “leave themselves susceptible to personal injury claims or litigation if somebody gets ill”.
The duty of care extends to vulnerable workers, including pregnant women, those with health conditions, and those on certain medications. Where a risk cannot be avoided, employers may need to suspend the employee on full pay. It also applies to employees working from home, who may need homeworking risk assessments and potentially the provision of fans.
Trade unions have long pressed for change. The Trades Union Congress (TUC) has advocated for a legal maximum working temperature since 2008. It recommends that employers take action when temperatures exceed 24°C and proposes a maximum of 30°C (or 27°C for strenuous work) at which work should stop. The TUC also calls for investment in climate-resilient workplaces. The concept of “heat strikes” — protests, lunchtime walkouts and lobbying — has been proposed as a form of direct action by workers and climate justice groups. Under Section 44 of the Employment Rights Act 1996, workers can remove themselves from situations they reasonably believe pose a “serious and imminent danger”, but this protection is generally reserved for immediate safety risks rather than general discomfort from heat.
Schools: no mandated limit, but mounting calls for one
As with offices, there is no official legislation or guidance setting a maximum temperature for schools. The Department for Education (DfE) says it does not typically advise schools to close during hot weather “because school attendance is the best way for pupils to learn and reach their potential, and hot weather can usually be managed safely.” The majority of schools in the UK are set to remain open during this heatwave, though some have opted to close early. Teachers have told The i Paper that students cannot concentrate in the heat, raising the prospect of lost learning.
The DfE suggests that schools relax uniform rules, allowing children to wear looser, light-coloured clothing and sunhats; provide and encourage children to drink more water; ensure classrooms are well ventilated; and discourage vigorous physical activity during the day. While not legally required, the National Education Union (NEU) recommends a maximum working temperature of 26°C in classrooms, and studies indicate that learning is best supported at between 20°C and 22°C.
The Climate Change Committee and the TUC have both supported demands for a maximum temperature limit in classrooms that would allow schools to close when it gets too hot. The DfE has said that it is “carefully considering” these recommendations, and Education Secretary Bridget Phillipson has not ruled out changes to the current guidance.
Parental rights when schools close
If schools do close, working parents may face a scramble to arrange childcare. Needham explained that under the Employment Rights Act, employees are legally entitled to unpaid time off to handle a crisis involving a dependent, which would include extreme weather. The policy is the same as for snow days: employees can expect one to two days off to make alternative care arrangements. In more extreme circumstances, they may need to discuss taking annual leave or unpaid leave with their employer. “If we continue to see these hot summers coming and becoming more frequent, there may be some change to the current policies,” she added.