While Britain swelters in tarmac-melting 30°C-plus temperatures this week, staff working in kitchens have had to endure temperatures rising as high as 65°C.

A snapshot poll on Caterer's website CatererSearch found the average temperature in 30 kitchens around the country was 44°C, although nearly a third had recorded temperatures above 50°C.

The How Hot is Your Kitchen? online survey reveals that some chefs are working in furnace-like temperatures of up to 65°C during this summer's heat wave.

In the capital, Tom Aikens admitted temperatures at his eponymous Michelin-starred Chelsea restaurant had reached 50°C during evening service last week. "In this country we're not geared up to deal with this kind of heat, so we just have to drink loads of water and squash and get on with it," he added.

Nigel Haworth, chef-patron of Northcote Manor, Langho, Lancashire, admitted: "It's very hard for everyone at this time of year, but we try to turn off unnecessary equipment like hot plates and adapt menus to use less heat, but it is tricky when you're busy."

The rising mercury has prompted the British Hospitality Association's food and technical affairs adviser John Dyson to call for the Health & Safety Executive (HSE) to introduce an upper temperature limit for workers.

"It's a question of ensuring that people can work in comfortable conditions and 44°C is not comfortable for anyone," he said. "The HSE needs to look at this issue and come to a conclusion. Weather conditions have changed dramatically and high temperatures are getting higher and more frequent, raising significant health and safety issues."

But Barry Baker, principal inspector at the HSE, dismissed the idea of an upper limit - despite there being a lower legal limit of 13°C - arguing instead that during "abnormal heat waves" employers should act responsibly and manage the issue as they would any other health and safety issue.

"To impose a higher limit might encourage employers to run up to that limit, so our current goal-setting guidance will remain," he said. "We're facing abnormal temperatures, so what works in December may not work now. The bottom line is about adopting sensible risk-assessment principles, not implementing specific numbers. Employers must address what can be done mechanically, introduce more breaks, ventilation and make water available."

• To help us find out how hot it is in British kitchens this summer, fill in our survey. You could win a free subscription to Caterer and Hotelkeeper. Do you think there should be a legal upper working temperature? Let us know at www.caterersearch.com/forums.

Heat stress: How to reduce the risks

• Control temperature using fans, air conditioning and physical barriers to reduce exposure.
• Provide mechanical aids to reduce workloads.
• Reduce the length of exposure to hot environments - provide regular cool rest periods.
• Prevent dehydration by encouraging workers to drink cool water before, during and after work.
• Provide cool clothing - use breathable fabrics for staff uniforms.
• Provide training for workers. 
• Allow workers to acclimatise to the environment.
• Identify susceptible employees, eg, pregnant women or workers with heart conditions.
• Monitor the health of workers at risk.
  
  Source: HSE
  
  Typical symptoms of heat stress
• Inability to concentrate
• Muscle cramps
• Heat rash
• Severe thirst
• Fainting 
• Heat exhaustion - fatigue, giddiness, nausea, headache, moist skin
• Heat stroke - hot dry skin, confusion, convulsions and loss of consciousness

Source: HSE

By Emily Manson