The Health and Safety Executive suggests the minimum temperature in a workplace should normally be at least 16 degrees Celsius, but there is no equivalent maximum in law or guidance. Many workplaces are so hot they cause adverse consequences to employees, including passing out.
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The Government should set a maximum temperature for all indoor workplaces in law. For working environments such as offices this could be around 30 degrees Celsius, and for environments involving strenuous labour it should be lower, at around 26 degrees Celsius.