The chefs turning down the heat by switching from gas to electric

As well as being quieter, cheaper to run and easier to clean, induction cookers can cut kitchen temperatures by up to 10C

Leaping flames, searing heat, copious sweat and scorchingly inventive swearing - restaurant kitchens are never a place for the faint-hearted, but this summer they have been sweltering in successive heatwaves to a dangerous degree.

Some restaurants, cafes and bakeries in the UK grew so hot that they were forced to close, or reduce their hours, for the safety of their staff. There is still no maximum working temperature, despite calls from the TUC, and tens of thousands of kitchen staff are thought to have carried on working in furnace-like" conditions.