Feeling the heat: a workplace guide to handling heatwaves
For years, the UK’s approach to workplace heat has largely been to complain about it while carrying on regardless. But prolonged heatwaves are becoming more common, and they bring genuine legal and practical challenges for employers. From pregnant employees and disabled staff to school closures, wildfire disruption and cancelled holidays, extreme weather has a habit of creating employment law issues long before anyone reaches for the sunscreen.
So, what should HR actually be thinking about?
There is (currently) no maximum workplace temperature
One of the most common misconceptions is that employees can simply stop working once the office reaches a particular temperature. They cannot. Unlike minimum workplace temperatures, there is currently no legal maximum temperature for workplaces in England. The Trades Union Congress (TUC) has repeatedly called for legislation introducing a maximum indoor working temperature of 30°C, or 27°C where work is physically strenuous. Those proposals have attracted considerable publicity, but they have not become law.
That does not mean employers can ignore the issue. Under the Health and Safety at Work etc. Act 1974, employers must ensure, so far as is reasonably practicable, the health, safety and welfare of employees. The Workplace (Health, Safety and Welfare) Regulations 1992 also require indoor workplace temperatures to be “reasonable”.
What is reasonable will depend on the circumstances. An air-conditioned office and a warehouse loading bay are very different environments.
Risk assessments matter
Heat should be treated like any other workplace hazard.
During periods of extreme weather, employers should review their health and safety risk assessments and consider measures such as:
- increasing ventilation or cooling;
- providing free drinking water;
- allowing additional rest breaks;
- relaxing dress codes where appropriate; and
- rescheduling physically demanding outdoor work to cooler parts of the day.
There is no statutory maximum temperature for outdoor work either. However, where employees are undertaking strenuous physical work in extreme heat, employers should carefully consider whether the work can safely continue. The legal question is not whether it is hot, but whether the risks have been reduced so far as reasonably practicable.
Some employees may need more protection than others
It’s important to remember that heat does not affect everyone equally. Equality Act 2010 obligations may require employers to make reasonable adjustments for disabled employees whose conditions are exacerbated by high temperatures. That could include altered working hours, additional breaks, homeworking, relocating workstations or providing cooling equipment.
Pregnant employees also deserve particular attention. Pregnancy can increase vulnerability to heat-related illness, and employers should review pregnancy risk assessments where high temperatures create additional risks. What was safe in April may no longer be appropriate during a July heatwave.
Managers should also know the warning signs of heat exhaustion, dehydration and heat stroke, and be prepared to act quickly if employees become unwell.
Flexibility can avoid bigger problems
Sometimes the simplest adjustments are the most effective.
Allowing earlier start and finish times, avoiding physically demanding work during the hottest part of the afternoon, or permitting temporary homeworking may all reduce both health risks and operational disruption.
For employers with multiple sites, it is also worth remembering that conditions can vary significantly across the country. The Met Office’s regional colour-coded heat alerts provide a useful trigger for escalating workplace measures, rather than relying on a one-size-fits-all approach.
Heat creates practical HR headaches too
Not every heatwave problem arises inside the workplace.
Schools occasionally close because buildings become unsafe, leaving parents needing emergency childcare. Wildfires, transport disruption and power failures may prevent employees reaching work. Holiday cancellations owing to extreme heat in the destination country (thinking of the current situation in Madrid and Southwest France) can also result in employees seeking to rearrange booked annual leave at short notice.
These situations will not be governed by any special ‘heatwave rights’. Instead, employers will be dealing with existing legal frameworks, such as statutory time off for dependants under the Employment Rights Act 1996, annual leave rules or flexible working arrangements.
Having sensible policies, and empowering managers to exercise reasonable discretion, will often resolve issues more effectively than trying to apply rigid rules.
Could employees resign and claim constructive dismissal?
Potentially, although only in exceptional cases.
If an employer repeatedly ignores obvious health and safety risks arising from extreme temperatures, refuses to carry out risk assessments or simply dismisses legitimate concerns, there is at least the possibility of constructive dismissal claims. The legal threshold remains high, but persistent failures to protect employee health could amount to a fundamental breach of the implied duty of trust and confidence. Fortunately, these situations are usually avoidable.
A little preparation goes a long way
The best response to heatwaves is usually not complicated. Before the next spell of hot weather arrives, ask yourself:
- Have we reviewed our health and safety risk assessment to address the risks posed by extreme heat?
- Do managers know what practical measures they can implement, such as adjusting working hours, relaxing dress codes or providing additional breaks?
- Have we identified employees who may require individual consideration, including pregnant employees and those with disabilities or underlying health conditions?
- Do we have a plan for outdoor work or physically demanding roles if temperatures become extreme?
- Have we considered how we will deal with transport disruption, school closures or workplace closures caused by extreme weather?
- Could we link our response to the Met Office’s colour-coded heat alerts so that managers know when different measures should be introduced?
- Are managers able to recognise the signs of heat exhaustion, dehydration and heat stroke, and do they know what action to take?