Hot, hot, hot - maximum temperatures at work

  • Insight

25 July 2019

Many workers are saying "you can't make us work in this heat" and asserting that there is a maximum temperature beyond which an employee is entitled to go home. There isn't.

For a number of years the TUC has expressed a need for legislation on a maximum temperature. Previous early day motions on the point have also failed to change the law.

What then are employers required to do to ensure that the workplace is tolerable?

The Workplace (Health, Safety and Welfare) Regulations 1992 provides that:  ‘During working hours, the temperature in all workplaces inside buildings shall be reasonable.’  Those who work voluntary unpaid overtime outwith working hours are therefore entitled to even less protection?  What are “working hours”? What is “reasonable”?  A safe and reasonable temperature in which to teach Zumba is likely to be different from that in which a night watchman might be comfortable.  The Approved Code of Practice which accompanies the Regulations suggests a minimum temperature should normally be at least 16 degrees Celsius, or 13 degrees Celsius if much of the work involves severe physical effort, so Zumba studios can be quite cold.  No maximum temperature is specified.

The Health and Safety Executive has observed that:  “An acceptable zone of thermal comfort for most people in the UK lies roughly between 13 degrees Celsius and 30 degrees Celsius”.  It might be considered that such a broad range is unhelpful.  However, the HSE is of the view that it is difficult to give a meaningful figure for a maximum temperature. There are factors other than air temperature which determine “thermal comfort”, including humidity and air movement and the interplay between the factors becomes more complex as temperatures rise.  A room with a constant temperature of 21 degrees Celsius, a constant humidity level and no air movement may be considerably less comfortable than a room with good circulation, lower humidity and a higher temperature.

How then can an employer or an employee judge whether the temperature is “reasonable” in terms of the Regulations?  Many workplaces will have employees sitting next to radiators on at full blast while their colleagues clamour to open a window and contribute to global warming.  Is the temperature in that workplace “reasonable”?

HSE considers 80% of occupants to be a reasonable measure for determining whether a workforce is "thermally comfortable".   However, a risk assessment is recommended if, depending on the workplace, 10 - 20% are complaining.  So temperature is not the measure; what matters is the number of disgruntled employees.  If it’s only 10% then the HSE advice is essentially that employers shouldn’t over worry – there’s no pleasing everyone. If it crosses the 10% threshold, then action may be required.

If an employer has failed to maintain a reasonable temperature in a workplace, in theory at least, they could be prosecuted.  Alternatively, they may be sued for any personal injury suffered but only if that was foreseeable.  Might employees resign and claim constructive dismissal?  There is an implied contractual duty to provide a suitable working environment which is broader than the health and safety duty.  In 1980 a case was brought successfully against an employer who required a workshop employee to work in temperatures of 9 degrees Celsius in winter.  However, few people would want to render themselves unemployed in this climate (sorry...).

Could a male employee bring a claim of indirect sex discrimination? The stereotypical view is that women feel the cold more than men.  Could maintaining workplace temperatures at higher levels allow men to argue that, in breach of the Equality Act 2010, they have been put to a “particular disadvantage” as compared with females? It may be difficult for a claimant to present evidence which establishes that, in fact, the stereotype holds true.   However, employers with a dress code which effectively requires males to wear warmer clothing might be at risk of a claim from a particularly zealous employee; nonetheless it is difficult to imagine such a claim being worth very much in the event the employee continued to work there.

The advice to employees has to be, if fewer than 10% of your colleagues are complaining, get over it and chill out (I know...)!

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