Working in a heatwave: how hot is too hot to work?

As the UK faces soaring temperatures, employers will have to be aware of their responsibilities and duty of care for staff 


Person struggling to work in the heatwave

The Met Office has issued its first ever red extreme heat warning in expectation of the UK heatwave reaching its peak on Monday and Tuesday. 

The national weather service has recommended making “substantial changes in working practices and daily routines”, with temperatures in London and the South of England potentially rising to 40C. This would top the highest ever recorded UK temperature of 38.7C, in Cambridge in July 2019. 

With the mercury rising, many people have been left wondering whether there is a maximum temperature that people can be expected to work in. But no such laws are currently in place. 

James Willis, head of employment law at Stevensdrake Solicitors, says: “A number of myths have arisen over the years around the notion that there are strict maximum and minimum temperatures beyond which employees cannot be required to work. However, no such restriction has ever been introduced.” 

An Early Day Motion to set a maximum workplace temperature of 30C – or 27C for those doing strenuous work – was recently tabled in Parliament and has so far been signed by more than 40 MPs. But currently, the law is much harder to pin down, with employers only required to provide a “reasonable” workplace temperature. 

“What is ‘reasonable’ will depend on the circumstances of each case,” Willis adds. 

Law on working in hot conditions

Despite the fact there is no guidance for a maximum workplace temperature limit, employers will have to be aware of any health and safety law. 

This requires organisations to keep the temperature at a comfortable level and provide clean and fresh air. 

The Health and Safety Executive (HSE) recommends that employers should “consult with employees or their representatives to establish the means to cope with high temperatures”. 

If the temperature becomes uncomfortably hot, employers should take all reasonable measures to achieve a more bearable temperature, according to HSE. This could include providing desk fans, shading windows or moving workstations away from direct sunlight. 

Organisations that fail to take sufficient measures to make working temperatures more comfortable could find themselves falling foul of their health and safety responsibilities. 

Under the latest red alert, the Met Office warns that “population-wide adverse health effects” could be experienced, not limited to those most vulnerable to extreme heat. This means that employers will also need to be conscious of Section 44 of the Employment Rights Act. 

Joseph Lappin, head of employment and partner at law firm Stewarts, explains that the act “provides a right for employees to stay at home if they reasonably believe that going to work places them at risk of serious and imminent danger”. 

He adds: “An employer who refuses to pay an employee who refuses to turn up to work, citing dangerous temperatures, may well find itself on the receiving end of an employment claim.”

How can employers make hot working conditions more comfortable?

With heatwaves becoming increasingly common in the UK, employers will have to consider the actions they can take to provide a safe working environment during periods of hot weather. 

For those in offices without air-conditioning facilities, now may be the time to invest. 

In addition to its air-conditioned HQ, HR software company CharlieHR will be advising staff to avoid commuting during busier periods and will be handing out ice creams and ice lollies to those coming into work. 

People and talent manager Finola Rance claims that the business will also be widening the scope of its wellbeing and learning budgets, allowing staff to use them to subsidise travel to and from the office on Monday and Tuesday, book a co-working space to avoid travel, and enjoy air conditioning or buy a fan to keep cool while working from home.

If it’s particularly bad on the day, the employer might have to be open to sending people home

Companies will need to demonstrate more flexibility than usual, too, according to Limelight HR founder Sally Bendtson. This could involve changing the hours people work so they can commute at cooler and less busy times, relaxing any formal dress codes or allowing people to work from home, if that will be more comfortable for them. 

She adds: “If the organisation has no air conditioning in the office and no access to ways of cooling people down, it might have to tell people not to come in or, if it’s particularly bad on the day, the employer might have to be open to sending people home.” 

For those who are not working in an office environment, there will be additional challenges. “It’s really difficult, especially if people are working outside under the sun,” Bendtson says. “Employers should make sure staff are covered up as much as possible and be sure to add in extra rest breaks.” 

Particular attention should be paid to those who are more vulnerable, whether because of their age or any health conditions, and those that are pregnant. Bendtson claims that, in such circumstances, a risk assessment can be useful.