The hot weather we are currently experiencing is becoming more common and can affect any workplace, whether your employees are working outside, travelling between sites, working in a warehouse, wearing protective clothing or simply spending long days in a warm office.
Most people welcome brighter days and warmer temperatures. However, when heat begins to affect concentration, hydration and physical wellbeing, it can become a genuine workplace safety concern. Employers need to understand the risks, put appropriate measures in place and make sure staff know what to do if someone becomes unwell.
Workplace first aid in hot weather is not only about responding to emergencies. It is also about preparation, early recognition and preventing a manageable situation from becoming serious.
Why Does Hot Weather Create Additional Risks at Work?
Heat affects people differently. A temperature that feels manageable to one employee may be more difficult for another, particularly where physical work, limited ventilation, protective clothing, direct sun exposure or existing health considerations are involved.
According to the Health and Safety Executive (HSE), heat stress occurs when the body’s ability to control its internal temperature starts to fail. The risk is influenced by more than the air temperature alone; humidity, work rate, clothing and personal protective equipment (PPE) can all contribute.
Your employees may be at greater risk when they are:
- Working outdoors in direct sunlight
- Carrying out strenuous or physically demanding tasks
- Working in kitchens, laundries, warehouses, factories or enclosed spaces
- Required to wear heavy clothing or PPE
- New to a hot working environment
- Affected by medication or a health condition that makes heat more difficult to tolerate
Heat can also affect judgement and concentration. In workplaces involving machinery, driving, lifting, manual handling or other physical hazards, an employee who is becoming overheated or dehydrated may be less able to work safely.
Is There a Maximum Legal Working Temperature in the UK?
There is no fixed maximum workplace temperature set in UK law. However, this doesn’t mean you can ignore excessive heat. The HSE states that employers must provide a reasonable indoor workplace temperature and must assess and control risks to employee health and safety, including risks associated with high temperatures. This applies whether work is carried out indoors or outdoors.
In practical terms, employers should consider hot weather as part of their risk assessment and introduce seasonal or temporary controls where necessary.
These measures may include:
- Improving ventilation or using fans or air conditioning where suitable
- Providing access to cool drinking water
- Altering work patterns or reducing strenuous tasks during hotter periods
- Scheduling outdoor work for cooler times of day
- Providing shaded rest areas
- Allowing more frequent breaks
- Reviewing whether PPE or uniforms increase the risk of overheating
- Ensuring employees understand the signs of heat-related illness
For employees working outdoors, the HSE specifically recommends access to cool water, shaded working or rest areas, more frequent breaks and rescheduling tasks to cooler parts of the day where possible.
Preparing Your Workplace for Hot Weather
Employers already have a responsibility to make sure employees can receive immediate help if they are injured or become unwell at work. This includes having an appropriate first aid kit, someone appointed to take charge of first aid arrangements and clear information for employees about those arrangements.
As temperatures rise, it is sensible to review whether your existing first aid provision remains appropriate for the risks in your workplace.
Review Your First Aid Needs Assessment
Hot weather may change the level or type of risk faced by employees, especially where staff work outdoors, in warm environments or undertake physical tasks.
Your first aid needs assessment should consider:
- The working environment and expected temperature conditions
- Whether employees will be working outdoors or away from the main site
- Access to water, rest areas and shade
- Whether staff are required to wear PPE
- The number of trained first aiders available during summer holidays
- Whether lone, mobile or remote workers may need additional arrangements
- How quickly emergency assistance could be accessed if someone became seriously unwell
A review does not need to be complicated, but it should lead to practical action where there is an identifiable risk.
Communicate with Staff Before Hot Weather Arrives
Your employees should know what arrangements are in place before temperatures become uncomfortable. A short briefing or staff notice can help remind people to drink regularly, take appropriate breaks and report early symptoms rather than trying to carry on.
Managers and first aiders also need to be aware that an employee may become unwell gradually. Someone who appears unusually tired, unsteady, confused or unable to concentrate may need support, cooling and assessment rather than being expected to continue working.
Recognising Heat Exhaustion at Work
Heat exhaustion occurs when the body becomes too hot and struggles to cool itself effectively. It should be acted upon quickly because, if symptoms worsen, it can develop into heatstroke.
Signs of heat exhaustion can include:
- Tiredness or weakness
- Dizziness
- Headache
- Feeling sick or vomiting
- Heavy sweating
- Pale or clammy skin
- Muscle cramps
- Thirst
- Fast breathing or heartbeat
- A high temperature
Changes in skin colour may be less noticeable on brown or black skin, so it is important to consider the full range of symptoms rather than relying on appearance alone.
What Should You Do if Someone Has Heat Exhaustion?
If an employee is showing signs of heat exhaustion:
- Move them to a cool place, ideally away from direct sun or heat sources.
- Remove unnecessary clothing, such as a jacket or excess PPE, where safe and appropriate.
- Encourage them to drink cool water, a sports drink or a rehydration drink.
- Cool their skin using cool water and fanning. Cold packs wrapped in a cloth may also be placed around the neck or under the armpits.
- Stay with them and monitor how they respond.
The NHS advises that someone with heat exhaustion should begin to cool down and feel better within 30 minutes. If symptoms are difficult to manage or advice is needed, contact NHS 111.
Recognising Heatstroke: When It Is an Emergency
Heatstroke is more serious than heat exhaustion and requires emergency medical attention.
Call 999 if someone:
- Is still unwell after 30 minutes of resting in a cool place, being cooled and drinking fluids
- Has a very high temperature
- Has hot skin that is not sweating
- Is breathing quickly or experiencing shortness of breath
- Becomes confused or uncoordinated
- Has a seizure
- Loses consciousness
If the person loses consciousness while waiting for emergency help, place them in the recovery position if they are breathing normally and continue to monitor them.
In a workplace emergency, early action matters. Employees should understand who to contact, where first aid support is available and when an ambulance should be called.
Preventing Dehydration During the Working Day
Dehydration can increase the risk of heat-related illness and may also affect a worker’s ability to function safely.
The HSE recommends that employers provide cool drinking water and encourage workers in hot conditions to drink frequently in small amounts. Employers should not rely on employees feeling thirsty before they take a drink, as thirst can already be a sign that dehydration is beginning.
Simple measures can include:
- Making cool drinking water easily accessible
- Encouraging regular drink breaks
- Ensuring mobile or outdoor workers carry water
- Reminding employees to stay hydrated before physically demanding tasks
- Providing suitable rest areas away from direct heat
These steps are straightforward, but they can make a significant difference to employee comfort and safety.
Do Your First Aiders Feel Confident Responding to Heat Illness?
First aid arrangements need to work in real-life situations. During hot weather, this means your first aiders and responsible staff should feel confident recognising heat exhaustion, beginning cooling measures and understanding when heatstroke requires emergency support.
It is also important to plan for annual leave and summer absences. If key first aiders are away, your workplace still needs adequate and appropriate arrangements in place.
Hot weather may only last for a limited part of the year, but the risks can arise quickly. Preparing in advance gives employees confidence that their wellbeing is being considered and helps managers respond appropriately if a problem occurs.
Workplace First Aid Training with STS First Aid
Warm weather should not prevent people from working safely, but it does require preparation. By reviewing working conditions, encouraging hydration, reducing heat exposure and ensuring staff understand the signs of heat-related illness, employers can help protect their teams throughout the summer months.
STS First Aid provides workplace first aid training designed to equip employees with practical, real-world skills. Whether you require Emergency First Aid at Work, First Aid at Work or tailored in-house training for your organisation, our experienced tutors can help your team prepare for emergencies with confidence.
Explore our workplace first aid training courses or speak to STS First Aid about the right training provision for your organisation.
