As temperatures rise, so do the questions. Can staff refuse to work if it gets too hot? Is there a legal limit? What are employers actually required to do?
If you have ever wondered whether the UK has a maximum working temperature, you are not alone. It is one of the most common questions we get when the weather warms up. The short answer is no, there is no legal maximum. But that does not mean employers can ignore the issue.
In France, and several other countries, there are clearer rules about when it becomes too hot to work. In the UK, the position is more flexible, which puts the responsibility firmly on employers to assess the risks and take sensible steps.
This blog looks at what the law actually says, what other countries do differently, and what UK employers should be doing when the heat arrives.
What the law says in France and other countries
In France, employers are required to take action when temperatures pose a risk to workers. This is particularly true for outdoor workers, where employers may need to adjust hours, provide shade and hydration, or in some cases stop work altogether.
Other countries take similar approaches. Spain, Germany and parts of the United States all have rules or guidance that set clearer expectations about working in extreme heat.
The detail varies from country to country, but the principle is the same. When temperatures reach a certain point, employers have specific obligations to protect their workforce.
What the law says in the UK
The UK does not have a legal maximum working temperature. There is no point at which work must automatically stop because it is too hot.
However, that does not mean there are no rules. The Health and Safety at Work Act requires employers to ensure, so far as is reasonably practicable, the health, safety and welfare of their employees. The Workplace (Health, Safety and Welfare) Regulations add that temperatures in workplaces should be “reasonable” during working hours.
The Health and Safety Executive provides guidance on managing workplace temperatures, but it does not set a specific number. Instead, it focuses on risk assessment and taking appropriate steps based on the circumstances.
What this means in practice is that employers cannot simply wait for a legal threshold to be triggered. They need to assess the risks and act accordingly.
What “reasonable” actually means in practice
The word “reasonable” can feel vague, but it is designed to reflect the reality that different workplaces have different challenges.
An office with large windows and no air conditioning is a different environment to a warehouse with high ceilings and good ventilation. A kitchen or a laundry will be hotter than a reception area. Outdoor work brings its own set of considerations.
Risk assessment is the key. Employers should think about:
- The working environment and how heat builds up
- The type of work being done and how physically demanding it is
- Individual factors such as pregnancy, health conditions or medication
- Whether staff are required to wear PPE or uniforms that make heat harder to manage
Reasonable does not mean perfect. It means taking sensible steps based on the situation.
What employers should do when it gets hot
When temperatures rise, there are practical steps employers can take to manage the risks and support their teams.
Hydration matters. Make sure staff have easy access to drinking water throughout the day. This sounds obvious, but it is easy to overlook in busy environments.
Allow more frequent breaks. Shorter, more regular breaks can help staff cool down and recover, especially if they are doing physical work or working in a hot environment.
Improve ventilation where possible. Opening windows, using fans, or adjusting air conditioning can all help. Even small improvements can make a difference.
Relax dress codes if appropriate. If your normal dress code includes formal clothing, consider whether a temporary relaxation makes sense during hot weather.
Consider flexible working. Earlier start times, later finishes, or remote working may all be options depending on the role. If staff can work from a cooler environment at home, that may be worth considering.
Communicate with your team. Let staff know what steps you are taking and encourage them to speak up if they are struggling. A bit of openness goes a long way.
Keep an eye on vulnerable staff. Some employees may be more affected by heat than others. Pregnant employees, those with certain health conditions, or those taking particular medications may need additional support.
What about outdoor workers?
Outdoor workers face different challenges. Construction, landscaping, delivery, events and similar roles all involve working in direct sunlight or without the benefit of air-conditioned spaces.
For these workers, employers should think about:
- Providing shade where possible
- Ensuring access to drinking water
- Scheduling physically demanding work for cooler parts of the day
- Allowing more frequent rest breaks
- Providing appropriate clothing, hats and sunscreen
- Training managers to recognise the signs of heat exhaustion and heatstroke
Heat-related illness is a real risk. Symptoms can include headaches, dizziness, nausea, confusion and fainting. Managers should know what to look for and how to respond.
Can employees refuse to work if it is too hot?
This is a common question, and the short answer is not automatically.
There is no legal right to stop work simply because the temperature is uncomfortable. However, if conditions are genuinely unsafe, employees do have the right to raise concerns. Under employment law, workers are protected from detriment if they raise legitimate health and safety issues.
In practice, most situations are best resolved through conversation rather than confrontation. If an employee says they are struggling with the heat, the sensible response is to listen, assess the situation and see what adjustments can be made.
If you are taking reasonable steps and communicating openly, most employees will appreciate the effort even if conditions are not ideal. If in doubt, document the steps you have taken so you can show you acted responsibly.
What happens if you get it wrong?
Failing to manage heat in the workplace can create real problems.
From a legal perspective, the Health and Safety Executive can take enforcement action if employers are not managing risks properly. In serious cases, this could include improvement notices or even prosecution.
From an employment perspective, employees who feel their concerns are being ignored may raise grievances. In extreme cases, an employee who resigns because of unsafe conditions could potentially claim constructive dismissal.
There is also a reputational risk. Staff talk, and a business that ignores welfare issues will find it harder to recruit and retain good people. On the other hand, handling hot weather well can build trust and show your team that you take their wellbeing seriously.
A note on common sense
Most employees understand that their employer cannot control the weather. They do not expect miracles. What they do expect is that you take reasonable steps and communicate openly about what you are doing.
Sometimes, small gestures make a big difference. Ice lollies in the freezer, permission to leave early on the hottest day, or a temporary relaxation of the dress code can all signal that you care about your team’s comfort.
The goal is not to be perfect. It is to be thoughtful.
What this means for employers
France may have a legal heat limit, but UK employers still have clear responsibilities. Hot weather is a health and safety issue, not just a comfort issue.
A bit of planning and flexibility now can prevent problems later. Review your risk assessments, think about what adjustments you can make, and communicate with your team before the next heatwave arrives.
How we can help
At Supportis, we help SMEs stay practical, compliant and confident when it comes to health and safety and people management.
If you need help reviewing your policies, updating your risk assessments, or thinking through how to manage hot weather in your workplace, we are here to help.
Get in touch with us for practical, no-nonsense HR support.
