Employees at a sportswear store in Colliers Wood have reportedly walked out due to 'unbearably warm' working conditions.

Staff at JD Sports in the Tandem Centre say the shop's air conditioning is broken and that shop temperatures have reached around 30 degrees. They say two employees were sent home with heat exhaustion in the last two weeks.

Yesterday's (June 19) walk-out wss the second this week, after seven left work the previous when temperatures soared to over 30 degrees across the UK over the weekend.

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A source told the Wimbledon Guardian that five employees walked out half way through their shifts yesterday. They said it was impossible to work in the stifling heat while running up and down stairs to grab stock for customers.

The workers also say there is no drinking water available on site, and they are forced to dash to shops and pay for their own bottled water.

The employees allege tap water in a communal staff room is contaminated, despite a sign stating it is for drinking.

A spokesperson for JD Sports said: "JD is fully aware of the current issue with the air conditioning at our Colliers Wood store, which came to our attention in May 2017. Engineers have visited the site and have ordered the necessary parts to repair the air conditioning, which will be completed on Thursday.

"We are aware that conditions have been very hot and are sorry that some staff have felt unable to remain in the store.

"We have relaxed staff uniform requirements and are working to repair the air conditioning as soon as possible.

"We are not aware of any issues with the drinking water, which comes direct from the mains, but will investigate any issues raised fully.”

The TUC (UK Trade Union Centre) called for new regulations this week that would allow workers to go home if the temperature of their workplace reached 30C (or 27C when doing physical activity).

A spokesperson for the TUC said: “Air conditioning can be a lifeline during these scorching temperatures. However, it must be properly installed and work when needed most.”

Current legal requirements covering temperatures in the indoor workplace say that employers must provide a "reasonable" temperature in the workplace, but an upper limit has not been legally set. The Workplace (Health, Safety and Welfare) Regulations 1992 say employers should carry out a risk assessment if a significant number of employees are complaining about the temperature.