With temperatures across the UK regularly reaching levels that were once considered unusual, it’s becoming increasingly important to understand the difference between heat exhaustion vs heatstroke.
Although the two conditions are related, they are not the same.
Heat exhaustion is usually treatable with prompt first aid and cooling measures. Heatstroke, however, is a life-threatening medical emergency that requires immediate treatment.
Knowing how to recognise the difference could help save someone’s life.
At a Glance
| Heat Exhaustion | Heatstroke |
|---|---|
| Usually caused by dehydration and overheating | Body can no longer control its temperature |
| Person is usually sweating heavily | Sweating may stop and skin may become hot |
| Temperature usually below 40°C | Temperature usually above 40°C |
| Can often be treated by cooling the person | Always call 999 immediately |
| Serious but usually recoverable | Medical emergency |
What is Heat Exhaustion?
Heat exhaustion develops when the body loses too much water and salt through sweating.
It commonly occurs during periods of hot weather, particularly when someone is working outdoors, exercising or spending long periods in direct sunlight.
Common symptoms include:
- Heavy sweating
- Feeling faint or dizzy
- Headache
- Muscle cramps
- Nausea
- Tiredness
- Cool, pale skin
- Fast pulse
If recognised early, heat exhaustion can often be treated successfully without hospital treatment.
First Aid for Heat Exhaustion
If you think someone is suffering from heat exhaustion:
- Move them somewhere cool.
- Encourage them to lie down with their legs slightly raised.
- Give them plenty of water to drink.
- Loosen unnecessary clothing.
- Cool the skin using damp towels or cool water.
- Continue cooling until they feel better.
If they do not improve within around 30 minutes, or their condition worsens, seek medical advice immediately.
What is Heatstroke?
Heatstroke happens when the body’s temperature rises to dangerous levels and it can no longer cool itself.
Unlike heat exhaustion, heatstroke is a medical emergency.
Without prompt treatment it can damage the brain, heart and other organs.
Symptoms of Heatstroke
Watch for:
- Confusion
- Loss of consciousness
- Seizures
- Very high body temperature
- Hot skin
- Rapid breathing
- Severe headache
Someone with heatstroke may stop sweating altogether, although this isn’t always the case.
First Aid for Heatstroke
If you suspect heatstroke:
Call 999 immediately.
While waiting for the ambulance:
- Move the person somewhere cool.
- Remove unnecessary clothing.
- Cool them as quickly as possible using cool water, wet towels or ice packs wrapped in cloth.
- Fan them if possible.
- Continue cooling until emergency services arrive.
Do not delay calling for help.
Preventing Heat-Related Illness
Prevention is always better than treatment.
During hot weather:
- Drink plenty of fluids.
- Take regular breaks in the shade.
- Wear light-coloured clothing.
- Avoid strenuous activity during the hottest part of the day where possible.
- Look out for colleagues, particularly those working outdoors.
- Never leave children or animals in parked vehicles.
Employers should also consider carrying out suitable risk assessments during periods of extreme heat, particularly where staff work outside or in hot environments.
The NHS advises of these techniques on their website here.
The UK Health and Security Agency also give guidance on this
Why This Matters in the Workplace
Every summer, thousands of employees continue working despite feeling unwell because they believe they’re “just a bit hot.”
Recognising the early signs of heat exhaustion can prevent the condition developing into heatstroke.
This is one of the many practical situations covered during our workplace first aid courses, helping learners build the confidence to recognise medical emergencies and respond appropriately until professional help arrives.
The HSE give guidance on heat in the workplace, you can view it here.
Learn More
If you’re interested in developing the confidence to deal with medical emergencies in the workplace, take a look at our:
We also deliver regulated workplace first aid training from our venues in Yeovil, Taunton and Bridgwater, as well as on-site throughout Somerset and Dorset.
Ready to Learn Life-Saving Skills?
Whether you’re an employer looking to train your team or an individual wanting to gain a recognised qualification, we’re here to help.
Browse our upcoming course dates or contact us to discuss workplace first aid training tailored to your organisation.