The TUC is set to inspect workplaces across the UK to ensure that workers are being helped by bosses to cope with the heatwave.
The TUC said that heat can lead to people fainting, dehydration, tiredness and the loss of consciousness in extreme conditions and more than 1,000 trade union health and safety officials have signed up to the programme.
TUC general secretary Paul Nowak said, “Everyone should be safe at work, but working in a heatwave can be dangerous – especially when your employer wants you to carry on regardless.
“That’s why union reps are taking action this week to keep their workmates safe in the heat, and it’s why we’re calling on the government to strengthen legal protections with a maximum working temperature.
“A lot of the best safety steps are just common sense.
“For example, employers should allow flexible hours to avoid the hottest parts of the day. And indoor workplaces should be kept at comfortable temperatures, with relaxed dress codes.”