Employers have a legal obligation to provide a ‘reasonable’ temperature in their workplace under the Workplace (Health, Safety and Welfare) Regulations 1992. The regulations’ Approved Code of Practice (ACOP) suggests a minimum temperature in the average office of at least 16C so, during winter, it is easy for employers to manage as temperatures shouldn’t fall below this. However, the ACOP does not suggest a maximum temperature and during summer the debate between staff – and employers – about what’s an acceptable workplace temperature can become personal. There are many contributing factors to what feels like a ‘reasonable’ temperature for each individual. 

In your office, temperatures may differ depending on the location of your desk, and from person to person depending on personal circumstances. Someone who sits by an air conditioning unit may find the constant airflow unpleasant but be in an ongoing debate with nearby colleagues who argue that they are sweltering in what, for them, is a too hot environment. What the temperature ‘feels like’ depends on a number of different environmental factors, including air temperature, radiant temperature (direct heat from a source e.g. radiator), air velocity (wind) and humidity. It also depends on our own personal factors such as how many of items of clothing we’re wearing and our own metabolic heat (produced when we move or exercise).

It’s unlikely that you’ll achieve a wholly acceptable office environment where one temperature suits all, as to achieve thermal comfort you need to take into account both the environmental and personal factors mentioned above – factors that make up what is known as the ‘human thermal environment’. 

However, in addition to relaxing strict dress code policies on hot days, there are a number of steps that can be suggested to staff, if you want to improve thermal comfort in your workplace: 

• add or remove layers of clothing depending on how hot or cold you are

• use a desk or pedestal fan to increase air movement

• use window blinds (if available) to cut down the heating effects of the sun

• in warm situations, drink plenty of fluids

• if possible, work away from direct sunlight or sources of radiant heat

• take regular breaks to cool down in warm situations and warm up in cold ones. 

Ultimately, as an employer, the best that you can realistically hope to achieve is a thermal environment that satisfies the majority of people in the workplace or, put more simply, ensures they are in reasonable comfort. If you can achieve thermal comfort for 80 per cent of your employees, you will have met the Health and Safety Executive’s suggested limits for the minimum number of people who should be thermally comfortable in an office environment.