Retail trade union Usdaw has urged employers to take measures to protect workers from heat-related health and safety risks as temperatures rise, while renewing its call for a legal maximum workplace temperature.
The union said heat stress can increase the risk of accidents and injuries, with workers exposed to high temperatures potentially suffering from loss of concentration, irritability, dizziness, headaches, nausea and fainting.
Joanne Thomas, Usdaw general secretary, said employers should work with trade union health and safety representatives to introduce measures to mitigate the risks during periods of extreme heat.
“Heat stress is a real health and safety risk that can lead to more accidents and injuries,” she said. “As the temperature rises, heat exhaustion starts. People begin to suffer loss of concentration, irritability, dizziness, headaches, nausea and fainting.”
Thomas noted that while current regulations set a legal minimum temperature for indoor workplaces, there is no legal maximum workplace temperature. Instead, employers are responsible for assessing risks and providing measures such as temporary or local cooling, access to water and rest facilities where necessary.
“Despite the absence of legislation, we are calling on employers to take measures to keep workers safe and work with trade union health and safety reps to provide substantial measures to mitigate the risks,” she said. “No-one should have to work in extreme and dangerous conditions.”
Usdaw has long campaigned for a legal maximum working temperature of 30°C, or 27°C for workers undertaking strenuous work.
It is also calling for employers to be required to introduce cooling measures when workplace temperatures reach 24°C.
The union said it welcomed the recent recommendation from the Climate Change Committee for a maximum workplace temperature and urged the government to act on it.
“Workers deserve a legal right to be protected from the heat and as the world hurtles towards 1.5 degrees of warming, this issue is only going to become more of an urgent priority,” Thomas said.
Temperatures provisionally reached 38.1°C at Kew Gardens in London on Thursday (13 August), making it the fifth hottest day on record for the UK, the Met Office said.
The latest extreme heat also means 2026 has seen the most number of days reaching or exceeding 36°C (four days) and 37°C (three days) with it also equalling 2022 for seeing two days of 38°C.