What Is the UK Legal Temperature to Work In? Workplace Rights and Safety Explained
If you manage staff in the UK, it’s natural to ask what the “legal” working temperature is. The short answer is that there is currently no legal maximum workplace temperature for indoor work.
Still, there is a clear duty to keep conditions at a reasonable temperature and follow minimum temperature guidance.
Understanding Workplace Temperature Laws in the UK
UK law does not set a single maximum temperature figure, even for offices, schools or most other indoor workplaces. Instead, Regulation 7 of the Workplace (Health, Safety and Welfare) Regulations 1992 requires that during working hours, the temperature in all workplaces inside buildings shall be reasonable.
Health and Safety Executive (HSE) guidance gives widely used minimum temperature benchmarks for indoor workplaces. It states that temperatures should normally be at least 16°C for most types of indoor work, or 13°C where much of the work involves rigorous physical effort. These figures are guidance rather than hard legal limits, but they are often treated as the starting point for risk assessments and practical compliance.
Because there is no statutory maximum, employers must manage heat and cold using risk assessment rather than waiting for a specific number on the thermometer. The legal test is whether the temperature is reasonable for the work being carried out, taking into account the nature of tasks, clothing, ventilation and other environmental factors.
Minimum Temperature Guidance and Reasonable Conditions
For normal indoor work, workplace temperatures should usually be at least 16°C, and at least 13°C where work involves strenuous physical effort because body heat from activity helps to keep workers warmer.
However, reasonable temperature is not a single value that applies everywhere. What feels reasonable in a standard office will be different from a hot production line, a chilled warehouse or a care home where vulnerable people are present.
Thermal comfort depends on several factors, including air temperature, humidity, air movement, clothing, workload, and the time people spend in a particular area. Because of this, employers should avoid relying solely on a temperature reading. A more practical approach is to consider whether most people feel too hot or too cold, whether there are signs of heat stress or cold stress, and whether performance or safety is being affected.
Thermal Comfort and Risk Assessment
Thermal comfort is the preferred concept for managing workplace temperature. It describes a state where most people feel neither too hot nor too cold and can work without discomfort or health risk.
Two areas in the same building can have very different levels of comfort because of differences in air movement, radiant heat from equipment, humidity or clothing requirements.
Employers are expected to carry out risk assessments that cover both heat stress and cold stress, particularly during extreme weather or when work involves PPE, hot processes or chilled environments. These assessments should consider the type of work, the level of physical effort, how long workers spend in hotter or colder zones, ventilation, direct sunlight, and whether certain workers may be more vulnerable, such as pregnant workers or people with health conditions.
When conditions change, for example during a heatwave or a period of very cold weather, risk assessments should be reviewed and updated.
Managing Heat in Indoor Workplaces
Although there is no legal maximum temperature, employers must still take sensible steps when temperatures rise, and staff begin to experience discomfort or health impacts. Practical measures will vary by setting, but common actions include improving ventilation, reducing heat gain and adjusting how work is organised.
In factories, warehouses and kitchens, localised hot spots are common around ovens, plant and loading areas. Risk control often focuses on reducing how long staff stay in the hottest zones, rotating tasks, and scheduling the most physically demanding jobs for cooler times of day.
Providing shaded or cooler rest areas, access to cool drinking water and, where possible, access to cooler workstations can help reduce heat stress without stopping operations entirely.
In settings such as care homes or health facilities, the risks from high temperatures can be greater because residents and some staff may be more vulnerable to heat exhaustion or dehydration. Employers should review risks for individuals with underlying health conditions, adjust duties where necessary and monitor for early signs of heat-related illness.
Ventilation and Air Quality
Temperature control is closely linked to ventilation. Employers should provide clean, fresh air and adequate ventilation systems as part of creating reasonable working conditions.
Measures may include opening windows where appropriate, using mechanical ventilation or air conditioning, fitting blinds or shading to reduce solar gain, and insulating hot plant or pipework. These systems should be checked to ensure they still perform properly in extreme heat or cold and that they deliver fresh air rather than simply recirculating warm or stale air.
Fans can help with air movement, but in very hot conditions they may not be enough on their own, so employers may need to combine them with other controls.
Organising Work, Breaks and Records
How work is organised has a major impact on thermal comfort and safety. Many employers use job rotation, extra rest breaks and changes to start and finish times to reduce exposure during the hottest or coldest parts of the day.
Allowing staff to work earlier or later, shortening time spent in high-heat or low-temperature areas, and temporarily relaxing uniform requirements can all help.
Digital rota and time-and-attendance systems can support this by showing who is working where and for how long, making it easier to plan fair rotation and manage additional breaks. While this is not a legal requirement, accurate records can help demonstrate that managers have responded to workplace temperature risks in a structured way.
Effects on Performance and Wellbeing
High temperatures do more than cause discomfort. Heat stress can reduce concentration, slow work and increase the risk of errors and accidents.
As conditions become more extreme, absence linked to heat exhaustion or other heat-related health issues may rise, putting pressure on staffing and service delivery.
Employers should pay particular attention to workers who may be more susceptible to heat or cold, such as pregnant workers or those with cardiovascular or respiratory conditions. Occupational health advice can be useful when assessing individual risks and deciding on adjustments, additional breaks or temporary duty changes.
Cold Temperatures and Winter Working
Cold weather can be just as challenging as heat. The same 16°C and 13°C minimum guidance applies to normal indoor work and strenuous work respectively, but many workplaces, especially chilled storage, open loading bays or outdoor jobs, may not be able to maintain these temperatures continuously.
Where temperatures are lower than ideal, risk control should focus on limiting exposure, providing suitable protective clothing and creating warm rest areas where staff can recover.
Practical steps might include shortening time spent in the coldest parts of the workplace, scheduling tasks to avoid the coldest times of day, and ensuring workers have access to warm drinks and appropriate layers.
Cold stress can cause tiredness, shivering and reduced dexterity, which in turn can affect safety and work quality. This makes it important to review whether tasks, PPE and work patterns are suitable during very low temperatures, just as they would be during a heatwave.
Policy, Training and Communication
Because there is no fixed legal maximum temperature, employers benefit from having a site-specific policy for managing hot and cold conditions. This should set out who monitors workplace temperature and thermal comfort, when changes to work patterns or breaks are triggered, and how concerns can be raised and recorded.
Training is vital to make these policies effective. Managers and supervisors should know the signs of heat stress and cold stress, understand the control measures available to them, and be clear that action does not depend on reaching a single maximum temperature figure.
Good communication also means encouraging staff to report discomfort or emerging issues early so that adjustments can be made before health or performance are seriously affected. Safety representatives and employee feedback can help identify hot or cold spots and groups who may be at greater risk.
Frequently Asked Questions
Is there a legal maximum working temperature in the UK?
No. UK law does not set a legal maximum temperature for workplaces. Instead, employers have a duty to keep the temperature reasonable and to control risks from heat through practical measures.
What are the minimum workplace temperatures?
Indoor workplaces should normally be at least 16°C for most types of work, or 13°C where much of the work involves rigorous physical effort.
Can workers refuse to work if it is too hot or too cold?
There is no automatic legal right to stop work at a specific temperature. However, if conditions create a serious and imminent danger to health or safety, workers should raise concerns with their employer or safety representative, and employers should respond by reviewing risks and putting suitable controls in place.
Who enforces workplace temperature requirements?
The Health and Safety Executive is the main regulator for workplace health and safety in Great Britain, including workplace temperature obligations. In some settings, local authorities may also have an enforcement role.