Working in the summertime – can it be too hot to work?


Summer 2018 looks set to be a record breaker and media coverage continues to make comparisons with the long, hot summer of 1976. We’re reminded to drink lots and wear sunblock and basically take care, like you would on holiday. However, holidays usually mean the main worries are how long before you get in the pool again or how many ice creams it’s reasonable to eat in a day, whereas at home, working to pay for the holiday means getting the job done.

So, can it be too hot to work? Are employers legally required to keep the workplace temperature within a certain range? Should employees finish early if it gets too hot or be allowed to take a Siesta?

The short answer is no. There are not any specific legal requirements for employers to let employees go home when it’s hot. The Gov.UK ( guidance on workplace temperatures is that the temperature of all indoor workplaces must be ‘reasonable’. There is no law stating what the minimum or maximum working temperatures are, so it’s therefore down to the discretion of the employer. In terms of guidance by numbers, there is a minimum of 16°C, or 13°C if employees are engaged in physical work. But they’re exactly that – just guidance. They’re not enforceable by law.

The Health & Safety Executive (HSE) ( gives more detailed guidance, highlighting that employers have a duty of care towards their employees and should ensure that:

Thermal Comfort

According to the HSE, there are six factors of thermal comfort. Air temperature alone is not enough of an indicator of thermal comfort or, conversely, thermal stress. Both environmental and personal factors need to be considered. For example, environmental factors include:

  1. Air temperature
  2. Radiant temperature – any heat radiating from warm objects
  3. Air velocity – the speed at which air moves (for example, still or stagnant air that is artificially heated).
  4. Humidity – humidity levels can be said to be high when they are greater than 80%

And personal factors include:

  1. Clothing Insulation – particularly relevant if employees are required to wear protective clothing or PPE to work
  2. Metabolic heat – the amount of heat given off during physical activity.

It can be difficult to legislate on these, particularly personal factors. PPE is often a legal requirement, and metabolic heat will depend on the individual.

Avoiding conflict

If environmental factors are giving cause for concern then employees may be able to challenge their employer, through a trade union or the grievance process. It is important to remember that the employer has a duty of care to ensure a safe and comfortable working environment, so if an employee considers that their wellbeing is being put at risk due to the working conditions, then it is important that this is raised and addressed. This is particularly important if the employee has an underlying health condition, like asthma, for example, that may be exasperated by extremes of heat, humidity, or poor quality air.

Ultimately, there is no set temperature limit in law, so legal redress options based on the temperature alone are limited, but the employer will have to ensure that they have assessed the risks, implemented reasonable steps to ensure a comfortable working environment and that they treat any specific grievances fairly and reasonably.

2018 looks like being a year of extreme weather, but reasonableness in the workplace should ensure it is not memorable for workplace disputes.

Julie Taylor

Employment Law

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