Marianne McJannett

Periods of extreme heat are becoming more common in the UK, raising important questions about workers’ rights and employers’ legal obligations. While many assume there must be a legal “maximum temperature” at which work must stop, UK employment law takes a different approach. Instead of fixed limits, the law focuses on health and safety, risk management and reasonableness.

So, what is the legal framework around employer duties and employee protections relating to working in high temperatures?

In a week where Disneyland Paris closed its outdoor rides due to extreme temperatures, many UK schools shut their doors and public transport is severely disrupted – not to mention where we’re seeing footballers being given hydration breaks to manage the heat at the World Cup – a lot of discussion is taking place around whether it is “too hot” to work.

A common misconception is that UK law sets maximum and minimum workplace temperatures. However businesses must follow guidelines set out in health and safety at work law, which require employers to provide a reasonable indoor temperature in the workplace during working hours, depending on the nature of the workplace and the type of work being carried out.

This principle comes from the Workplace (Health, Safety and Welfare) Regulations 1992, which apply to most indoor workplaces. The absence of a fixed limit reflects the fact that some industries (e.g. foundries or kitchens) operate safely at higher temperatures with appropriate controls in place.

Several key pieces of legislation govern working conditions in hot weather. The Health and Safety at Work etc. Act 1974 places a general duty on employers to ensure, so far as reasonably practicable, the health, safety and welfare of employees; the Workplace (Health, Safety and Welfare) Regulations 1992 require employers to maintain a reasonable indoor temperature and to provide adequate ventilation and fresh air. In addition, the Management of Health and Safety at Work Regulations 1999 require employers to carry out risk assessments, including where heat may create a risk to workers’ health and safety. Finally, the Employment Rights Act 1996 provides protection where employees leave or refuse to work in situations of serious and imminent danger.

Even without a maximum temperature, employers have clear legal duties to manage heat-related risks. Employers must identify hazards such as heat stress, dehydration and fatigue and then put in place control measures to reduce those risks. Heat is legally treated as a workplace hazard, like any other safety risk. Practical steps may include providing ventilation or air conditioning, allowing airflow by opening windows where appropriate and using blinds or shading to reduce heat exposure.

Employers are also expected to ensure that workers have access to drinking water, suitable rest breaks and, where possible, cool or shaded rest areas. Depending on the circumstances, employers may also adjust working hours, introduce earlier starts, rotate duties or relax dress codes where it is safe to do so. Additional care is required for pregnant employees and for workers with health conditions or disabilities. Where heat creates an additional risk, employers must consider and make reasonable adjustments.

Employees can report uncomfortable or unsafe temperatures and request adjustments or a risk assessment. Employers are expected to consult with staff on temperature issues and to respond reasonably to concerns raised.

While UK law does not specify a maximum working temperature, it places significant responsibility on employers to ensure safe and reasonable working conditions during hot weather. The emphasis is on risk assessment, prevention and employee welfare and this is something that employers will need to factor into their overall risk assessment approaches, particularly as very hot summers become a more common occurrence.

Marianne McJannett is a partner at Aberdein Considine LLP