When is it too hot to work? Legal experts reveal your employee rights in a heatwave

As the UK boils in its record-breaking heatwave, health experts have advised employers to allow staff to work from home and adjust workplace protocols. But with the Met Office now warning that temperatures could reach 41C in London on Monday, people are rightfully asking: when is it too hot to work?

Britain's sweltering heatwave has been anything but sunny this week, leading to a nationwide disruption of services and the endangerment of people's health across the country. 

The Met Office issued the UK's first ever red extreme heat warning at the weekend, while a national emergency has been declared by the UK Health Security Agency with a Level 4 Heat Alert. Both of these warnings are in place from Monday to Wednesday, with predictions that London could experience record-breaking temperatures of 41C over the next 48 hours.  

Transport for London's (TfL) chief, Andy Lord, has also urged people to avoid public transport unless absolutely necessary until the scorching temperatures lower. 

With the public manically wondering how to keep cool in the summer fever, trade unions have called for an improvement in employees' rights when it comes to working in hot conditions. There is currently no maximum working temperature in the UK, because some workplaces, like kitchens, are hot all the time. 

The GMB union has since called for the government to set a maximum temperature for workplaces of 25C, whilst the Trades Union Congress (TUC) has asked that staff be allowed to stop work if temperatures rise above 30C. Unions have also asked that employers make special accommodations for workers in the heat, including a relaxation of dress codes and flexible working hours. 

While the law has yet to establish a maximum temperature for workplaces, employers are still required to look after the well-being of their staff. 

“Despite the absence of legal temperature limits, the Health and Safety at Work Act imposes a general duty on employers to ensure, so far as is reasonably practicable, the health, safety, and welfare at work of all their employees," explains Sarah Calderwood, Partner in the Employment team at Slater Heelis Solicitors. 

“Staff should be allowed to take certain steps to improve their comfort at work including taking off/adding clothing (within the limits of decency and practicality), avoiding working near heat sources or direct sunlight, and providing plenty of drinking water instead of tea and coffee when it’s hot. Employers should, where possible, take steps to facilitate these options, such as relaxing dress codes during heat wave conditions.”

William Walsh, partner in the employment team at law firm DMH Stallard, agrees that employers have an obligation to ensure the health and safety of their employees in the workplace and says that employers also need to remember that, if employees are working from home, the health and safety obligations still apply to that working environment.

He summarises that, "the risks should be much lower, as home workers are unlikely to be undertaking physical tasks and, even if they were told to stop working, those individuals would still be in their same home environment. But the issue should not be discounted altogether."

He says, if, for example, it was known that an employee was working from their home office set up in a small box room up in a loft conversion, where it could get uncomfortably hot, "they should be encouraged to move and, if necessary, given flexibility around their tasks to allow them to do so." 

Can employers force staff to wear a uniform in the heatwave? 

While employers are entitled to enforce uniform regulations, they are also required to consider the health and safety of their staff. This could mean making certain allowances, such as adjusting dress code rules, when employee welfare is at risk. 

"There is no general rule to say whether you must continue to wear a suit, or office wear, if temperatures spike," says Lewys Traylor, Legal Advisor at DAS Law. "This comes down to reasonable behavior on the part of both the employer and the employee.

"Most workplaces will have a dress code and guidelines on what they consider to be acceptable standards of dress in the workplace, but employers should consider what is reasonable, and excessive heat is a health and safety issue so should be considered when making any decisions."