During the recent spell of hot weather across the country, our Schools HR team has seen a significant increase in queries from schools about the impact of heatwaves on the workplace. Heatwaves are no longer unusual or exceptional events in the UK, with recent red and amber heat-health alerts issued by the UK Health Security Agency and the Met Office demonstrating that schools are increasingly expected to anticipate periods of extreme weather in the same way they plan for other foreseeable hazards such as snow, flooding and severe storms. As a result, schools should move beyond viewing extreme heat as a short-term inconvenience and instead recognise it as a significant health, safety, safeguarding, employment and governance issue requiring structured planning and robust risk management.
Children are particularly vulnerable to heat-related illness, and excessive temperatures can affect concentration, behaviour, learning outcomes and overall wellbeing. Staff may also face increased risks, particularly those who are pregnant, disabled, have underlying medical conditions, are older workers, or are required to wear personal protective equipment (PPE). Heatwaves can also lead to transport disruption, attendance difficulties, and staffing challenges, which can have an impact on employee wellbeing. As such, schools are increasingly expected to take a proactive approach to heat risk management rather than simply responding when temperatures become uncomfortable.
Most recently our team has seen demands from unions that schools close during heatwaves, threatened strike action over the issue and staff refusing to attend work. This is despite schools taking all reasonable steps to manage risk, and complying with DfE Guidance on Hot Weather and Heatwaves.
This briefing note outlines the relevant legal framework and highlights practical measures to help educational employers manage periods of extreme heat effectively.
What does the law currently say in relation to workplace temperatures?
HSE Guidance and the Health and Safety at Work etc. Act 1974
One of the most common misconceptions regarding heatwaves is that there is a legal minimum or maximum workplace temperature in the UK. Whilst guidance from the Health and Safety Executive (HSE) identifies minimum workplace temperatures of 16°C for sedentary work (and 13°C where significant physical exertion is involved), there is no corresponding legal requirement or guidance prescribing a maximum workplace temperature.
Instead, employers are required to maintain a reasonable temperature within indoor workplaces during working hours. What is reasonable depends on the circumstances, including the nature of the work, levels of physical activity, ventilation, humidity, occupancy levels, direct sunlight exposure and the needs of individual workers.
The primary legal obligations arising in relation to workers are governed by the Health and Safety at Work etc. Act 1974. Employers must ensure, so far as is reasonably practicable, the health, safety and welfare of staff whilst at work. Within the education sector, these responsibilities extend to pupils, volunteers, contractors, visitors and any other person who may be affected by the school’s activities.
The requirement to act “so far as is reasonably practicable” requires employers to take measures proportionate to the risks faced, balancing the likelihood and severity of harm against the cost, time and practicality of implementing control measures. In the context of heatwaves, schools are therefore expected to take appropriate steps to mitigate foreseeable risks associated with excessive temperatures.
Employers must also provide a safe working environment, safe systems of work, suitable equipment, adequate training and effective supervision. Heat can affect each of these areas by increasing fatigue, impairing concentration and contributing to accidents and illness. Heatwave planning should therefore be viewed as part of an employer’s broader health and safety responsibilities rather than a standalone issue.
Equality Act 2010
In addition to obligations under health and safety legislation, schools should be mindful of their obligations under the Equality Act 2010, noting that high temperatures can have a disproportionate impact on certain groups of staff and pupils. Particular care should be taken in relation to disabled staff, pregnant workers, older staff, individuals experiencing menopausal symptoms and those with underlying medical conditions. Excessive heat may increase the risk of heat-related illness and exacerbate existing respiratory, cardiovascular, neurological and other health conditions. Where necessary, schools could consider reasonable adjustments including relocating staff to cooler areas, providing additional rest breaks, allowing flexible working arrangements or providing access to cooling equipment. An individual risk assessment, in addition to your general risk assessment, may be required for staff falling into a vulnerable group or who identify individual concerns.
Employment Rights Act 1996
Schools should similarly be aware of the protections available to employees under the Employment Rights Act 1996 (“ERA 1996”).
Notably, employees are protected from detriment and dismissal where they take action over a health and safety issue at work. For example, an employee may be protected where they refuse to attend work because they reasonably believe there is a serious and imminent danger to their health and safety. Similarly they may be protected for raising health and safety concerns or making some other disclosure (“whistleblowing”) that constitutes a protected disclosure under ERA 1996. Discomfort or high temperatures alone will not typically meet this threshold, but the assessment will depend on all of the circumstances, including the nature of the work, the effectiveness of control measures and any individual vulnerabilities. For example, the risk to an employee with no underlying health conditions or other vulnerabilities undertaking sedentary work in a warm classroom may be different to the risk to an employee undertaking physically demanding outdoor duties during a heatwave or an individual who is pregnant or has an underlying medical condition.
Similarly, schools must ensure that there are effective mechanisms for staff to raise health and safety concerns, and for those concerns to be properly addressed, without suffering a dismissal or other detrimental treatment. Any dismissal because an employee raises a legitimate health and safety concern may be automatically unfair under ERA 1996. Well-documented heatwave risk assessments, together with appropriate control measures, can assist employers in demonstrating that foreseeable heat-related risks have been properly considered and managed, that the employee’s concerns have been acted upon and address, and that therefore any belief by the employee of serious and imminent danger was unreasonable.
Practical steps for Schools and MATs
Practical measures aimed at managing the risk of extreme heat conditions in the workplace include as follows:
1. Heatwave Policies and Planning
Schools and MATs should consider whether they have a dedicated heatwave or hot weather policy in place. Whilst many organisations have long-established procedures for managing snow, ice and other severe weather events, comparatively few have developed formal arrangements for responding to periods of extreme heat. Given the increasing frequency and intensity of heatwaves, educational employers should ensure that heat-related risks are addressed through a structured and proactive approach.
Any such policy should identify who is responsible for monitoring weather conditions and heat-health alerts, conducting risk assessments, implementing control measures and communicating with staff, parents and pupils. It should also set out procedures for responding to heat-related illness, supporting vulnerable individuals and making decisions regarding educational visits, school events, sporting activities and other outdoor commitments.
A useful starting point for reviewing local arrangements may be the joint guidance produced by trade unions within the education sector (the ‘Joint union heatwave protocol’), which provides practical recommendations on managing extreme heat in the workplace. Whilst not legally binding, the guidance provides practical recommendations, as approved by various unions operating across the sector. Our Schools HR team can assist with drafting policies, reviewing risk assessments and advising on heat-related employment and health and safety issues, to ensure the adoption of best practice protocols. We can also assist with any union challenge.
2. Monitoring Heat-Health Alerts
Schools and MATS should subscribe to Met Office and UK Health Security Agency Heat-Health Alerts and ensure that relevant senior leaders receive notifications promptly. Monitoring alerts enables schools to anticipate risks and implement appropriate measures before conditions deteriorate. Notably, employers should be aware that:
- Yellow Alert = hot weather may present risks to vulnerable individuals;
- Amber Alert = wider population risk and prompt implementation of protective arrangements across the school; and
- Red Alert = significant risk to life and widespread impacts across the population.
Schools and MATs should carefully consider health alerts to ensure risks are appropriate managed, and conditions are monitored routinely throughout the school day.
3. Heatwave Risk Assessments
Schools and MATs should regularly review heat-related risks, including indoor and outdoor environments, to identify practical methods to reduce them. This may include considering factors such as classroom temperatures, ventilation, humidity levels, direct sunlight exposure, physical activity, examination arrangements and the characteristics of school buildings. Particular attention should be paid to areas that are prone to overheating, including sports halls, assembly halls, temporary classrooms and rooms with extensive glazing. A general whole school risk assessment should suffice, but an additional individual risk assessment may be required for pregnant or vulnerable staff, or those who raise specific concerns about their individual needs.
Risk assessments should be kept under regular review throughout a heatwave, as conditions can change rapidly and should focus on ensuring appropriate control measures are in place. Risk assessments should be revisited if there is an incident relating to extreme heat or any other change in circumstances.
4. Managing School Buildings and Internal Temperatures
School and MAT leaders and site managers should identify buildings or rooms that are particularly susceptible to overheating and consider appropriate measures such as ensuring adequate ventilation, adjusting room allocations, increasing the use of shaded spaces or implementing longer-term estate improvements designed to improve thermal comfort and heat resilience. Blinds, curtains and other shades should be used in circumstances of direct sunlight, and you may wish to switch off unnecessary electrical equipment to reduce internal heat generation.
5. Adapting Activities and Daily Operations for students
Schools and MATs should consider whether activities can be modified or rescheduled to reduce exposure to excessive heat. PE lessons, sports days, fixtures and other physically demanding activities may need to be shortened, relocated, replaced with lower-intensity alternatives or postponed altogether. Educational continuity will remain an important consideration, but schools should be prepared to make reasonable operational adjustments where necessary to protect health, safety and wellbeing of all those on site. Encouraging staff to stay hydrated, and permitting refillable water bottles in the classroom, is another useful way to minimise the risk of heat-related illnesses.
6. Staff Wellbeing and Employee Relations
Excessive heat can contribute to fatigue, irritability, reduced concentration and diminished productivity, potentially affecting both staff wellbeing and educational outcomes. Temporarily relaxing dress codes, adjusting supervision arrangements, relocating workspaces and other reasonable accommodations can be considered to maintain staff wellbeing. In addition although not a legal requirement, small, inexpensive, provisions such as suncream for those working outside, electrolytes and hats/caps may help with staff morale particularly in those schools where there is significant unrest or union challenge.
7. Communication and Training
School and MATs should ensure staff know how to recognise and respond to heat-related illness and keep parents informed of any measures being taken, such as hydration reminders, uniform flexibility or changes to planned activities. Prompt action can help prevent more serious health issues.
8. Governance and Strategic Oversight
Trust boards and governors should regard heat-related risks are appropriately addressed in risk management, policies and risk assessments with suitable support in place for vulnerable staff an pupils. Given the increasing frequency of extreme weather events, Schools and MATs should also consider longer-term estate strategies aimed at improving heat resilience, including shading measures and ventilation improvements.
School Closures
The DfE is clear that its expectation is that schools should remain open wherever it is safe to do so. Attending school is also the best way for pupils to learn and reach their potential, and hot weather can usually be managed safely with practical adjustments. For some children and staff, depending on their home circumstances, it may be safer to be at school where there is sufficient shade, ventilation and larger spaces to keep cool. From a safeguarding perspective, vulnerable children may be at greater risk out of school than any risk posed by a heatwave in school.
Closure should therefore be a last resort, rather than a default position, where risks cannot be adequately managed through reasonable adjustments and control measures. Attendance remains important from both an educational and safeguarding perspective, and schools are often better placed than individual households to supervise children, encourage hydration, manage heat and monitor signs of heat-related illness.
Where temperatures create risks that cannot be effectively mitigated through reasonable adjustments and control measures, temporary closure may become necessary. Any such decision should be supported by documented risk assessments and a clear consideration of all available alternatives and mitigation measures.
Looking ahead
Heatwaves are no longer exceptional events and should form part of school and MATs wider health and safety, safeguarding and employment-related risk planning. By taking sensible, proportionate steps in advance, schools and MATs can better protect the health, safety and wellbeing of their communities whilst maintaining educational provision wherever possible.
Further reading:
- DfE Guidance ‘Hot weather and heatwaves: guidance for schools and other education settings’ 22 June 2026 – https://educationhub.blog.gov.uk/2026/06/hot-weather-and-heatwaves-guidance-for-schools-and-other-education-settings/
- HSE Temperatures at Work Guidance – https://www.hse.gov.uk/temperature/employer/index.htm
- HSE Workplace Temperatures Checklist – https://www.hse.gov.uk/temperature/workplace-temperature-checklist.htm
- Joint Union Heatwave Protocol 2023 – https://ascl.org.uk/Help-and-Advice/Leadership-and-governance/Health-safety-and-safeguarding/Joint-union-heatwave-protocol-new-guidance
- Acas Guidance – https://www.acas.org.uk/extreme-temperatures-in-the-workplace and https://www.acas.org.uk/acas-tips-to-help-employers-manage-hot-weather-at-work
This briefing is not intended to be a definitive statement of the law and is correct at the time of publication. It should not be taken as a substitute for professional legal advice. It does not represent the views of any organisation or author and should not be relied upon as legal advice for specific circumstances.
For further advice on this or any other HR or employment law issue for schools please contact our dedicated team of education employment lawyers on schoolshr@wslaw.co.uk or 0345 026 8690.