Firms are being urged to relax workplace dress codes to help staff cope with the heatwave, the TUC has urged firms to temporarily relax their dress codes and leave work all together if it gets too hot.
The advice will come as a particular relief for male office workers who are often expected to wear shirts, suits and ties to work.
Heatwaves are generally easier for female workers to dress for, as they are able to switch to smart short-sleeved dresses.
It comes as Sunday saw a high of 32C, the hottest day of the year so far and emergency services are on standby after the Government issued a level three amber heat alert as temperatures are set to increase further this week.
Temperatures are due to peak at 34C in certain parts of the UK – hotter than the Bahamas – before cooling down at least a few degrees by next weekend.
As well as allowing comfortable clothes, the TUC has suggested that any outside work is done in the morning or afternoon to avoid the searing heat of the mid-day sun.
The union organisation again called for a change in the law to let workers go home if the temperature reaches 30C or 27C for people carrying out physical work. At present there is no upper temperature limit at which workers have a right to leave work.
It also called for a change in the law to introduce a maximum indoor temperature, with employers obliged to adopt cooling measures when a workplace temperature reaches 24C.
Companies should supply workers with cool drinks and allow them to take regular breaks, advised the TUC.