Heatwaves at Work: What UK Employers and Employees Need to Know

Whilst some employees may think, “surely, it can’t be legal to expect me to work in this heat?”, the reality is that there is no fixed “maximum working temperature” under UK law. 

That being said, employers still have a legal duty to provide safe, reasonable and properly risk assessed working conditions. This includes managing the risks associated with requiring staff to work in excessive heat. 

This article looks at the legal framework governing working during heatwaves and explains how employment rights apply when workplace temperatures rise to potentially unsafe levels.

Health and safety obligations during extreme heat

Employers are required to ensure (so far as is reasonably practicable), the health, safety and welfare of their employees. This duty, set out in the Health and Safety at Work Act 1974, extends to managing workplace hazards, including excessive heat, which can pose significant risks especially when it comes to physically strenuous roles or in work environments with limited temperature control. 

In addition, the Workplace (Health, Safety and Welfare) Regulations 1992 provide that “during working hours, the temperature in all workplaces inside buildings shall be reasonable”. Whilst this also does not specify an upper limit, it reinforces the employer’s obligation to take active steps when it comes to maintaining a safe and comfortable work environment for their staff.

To ensure compliance with the above legal obligations, employers should regularly carry out suitable and sufficient risk assessments and keep these under review in line with the Management of Health and Safety at Work Regulations 1999. Risk assessments should factor in: temperature, hydration and ventilation, as well as the nature and intensity of the work. 

Is there a legal maximum working temperature in the UK?

In short, no – there is no set maximum workplace temperature. The Health and Safety Executive provides guidance on the minimum workplace temperatures:

• For sedentary work (e.g., administrative or office-based roles) – the temperature should be at least 16°C
• For physical work (e.g., manual labourers, warehouse operations or manufacturing based roles)  – the temperature should be at least 13°C

When it comes to considering when it’s “too hot” for staff to work, the key legal standard is whether the working environment temperature is “reasonable”. There is no one size fits all limit. What is considered reasonable is dependent on a myriad of factors, from the physical workplace to the nature of the job itself. In practice, this means employers should assess on a case-by-case basis what maximum temperature is reasonable for their staff. This should be supported of course by up to date risk assessments, which identify potential risks associated with extreme heat and help guide them on appropriate steps to take to minimise these risks. 

Employer responsibilities to manage heat risk

What steps can employers take to manage the risks identified? This will depend largely on what is identified in the relevant risk assessments but potential reasonable adjustments to the workplace may include: 

• Improving ventilation, for example by providing fans or air conditioning
• Adjusting working hours or patterns to avoid peak temperatures
• Reducing physically demanding tasks, where possible
• Allowing additional/flexible breaks 
• Relaxing dress codes
• Providing access to cool drinking water

It is worth noting that employees are not automatically entitled to these adjustments. What is considered reasonable will depend on the employer’s size and resources as well as the nature of the work itself. For example, air conditioning for an office setting could be realistic but in an outdoor construction setting would be impractical, if not impossible. 

Outdoor working comes with its own distinct risks during periods of excessive heat, such as exposure to direct sunlight. Employers with outdoor workers should address these risks through a separate tailored assessment where appropriate. For further guidance on the risks affecting outdoor workers and steps employers can take to protect them, please see the HSE’s official guidance here. 

What is clear in recent years, is that heat waves are no longer an anomalous occurrence in the UK and shouldn’t come as a shock to employers. Employers should be taking a proactive rather than a reactive approach when it comes to temperature control management. 

Employee rights, concerns and refusal of unsafe work

Workers are entitled to raise legitimate health and safety concerns where they believe that their working conditions are unsafe, or their employer may not be complying with their legal obligations. They are also legally protected from being subjected to a detriment or dismissed for having raised such concerns.

Only in very specific circumstances, namely where they reasonably believe that their working conditions pose a serious and imminent danger to their health or safety, can employees refuse to work. This is a rather high threshold and does not extend to simply feeling uncomfortable or “too hot”. Employees should therefore exercise caution before adopting this practice, as there is also a potential risk that refusing to work where this threshold is not met, even during periods of excessive heat, could result in disciplinary action. 

Instead, a practical first step would be for employees to raise their concerns internally, giving the employer the opportunity to review and address the issues. If employee concerns are not resolved, they can then be escalated formally (e.g. via the company’s formal grievance process or with the support of their Trade Union). 

It is therefore important for Employers to ensure that they have clear and appropriate reporting mechanisms in place for staff to raise health and safety concerns. Managers and HR should also receive appropriate training to address these concerns promptly and in line with the employer’s legal obligations. 

Vulnerable workers and specific risk considerations

Employers should give particular consideration to employees who may be more adversely affected by the extreme heat. For example, pregnant employees, older workers, and those with underlying health conditions. Exposure to excessive heat can increase the risk of heat exhaustion or heatstroke for these individuals, and may also exacerbate any pre-existing medical conditions. 

Workers that are required to use Personal Protective Equipment (PPE) are also exposed to an increased risk, as protective clothing and equipment can restrict airflow, trap heat and cause overheating. 

With this in mind, employers should consider whether their more vulnerable staff, including those who use PPE, have been properly considered within their risk assessments. 

Employers should also be mindful of their obligations under the Equality Act 2010. Where an employee’s health condition satisfies the definition of a disability, the employer’s duty to make reasonable adjustments is triggered. 

How Goughs can help

Goughs supports both employers and employees in navigating these issues with our specialist team in employment law providing practical, commercially focused advice on your rights and legal obligations. 

We can assist employers with implementing risk assessments, drafting relevant policies and advising on managing workplace challenges effectively. 

For tailored advice and further information, please visit www.goughs.co.uk or get in touch with Amber Ballans, Employment Solicitor.