Preparing for summer safely: dehydration and heatstroke

We’ve all been waiting for it, and it looks like the warm weather is finally here to stay. As temperatures rise, students are spending more time in the playground and outdoor learning spaces, increasing the likelihood of heat-related illnesses in schools.

Heat can indeed pose a significant hazard, and children are particularly vulnerable to hot weather due to their physiology, behaviours, and activity levels. Children under four years of age may be at increased risk, as well as those with underlying health conditions or taking certain medications.

Two of the most common conditions that can affect pupils during warm weather are dehydration and heat exhaustion, which can progress to heat stroke in more severe cases.

Understanding the signs, acting early, and knowing what to do can make all the difference.

What is dehydration?

Dehydration occurs when the body loses more fluid than it takes in. Children are particularly vulnerable as they may not always recognise thirst or remember to drink regularly during busy school days.

Common signs of dehydration include:

• Dry mouth, lips and tongue
• Headache
• Tiredness or low energy
• Complaints of dark yellow urine or infrequent toilet trips
• Sunken eyes (the skin under the eyes appears noticeably thin, hollow or dark)
• Dizziness or light-headedness
• Difficulty concentrating
  
  

Encouraging regular water intake throughout the day is one of the simplest and most effective ways schools can help prevent dehydration and other sun-related illnesses.

💡 Good to know

• Young children may not be able to tell others they are thirsty and are therefore more at risk of dehydration. (British Nutrition Foundation)

• Even mild dehydration can affect concentration, energy levels, and mood.
  
  

• Children aged 4 to 8 need 1.1 s to 1.3 litres of fluids per day. While girls aged 9 to 13 need 1.3 to 1.5 litres per day, it is advised that boys aged 9 to 13 drink 1.5 to 1.7 litres per day. (European Food Safety Authority)
  
  

Because dehydration can lead to heat exhaustion, it is important to ensure pupils drink enough throughout the day, especially in warm weather when the body loses more fluid through sweating.

What is heat exhaustion?

Heat exhaustion happens when the body becomes overheated and is unable to cool itself down.

It often occurs after prolonged exposure to heat, particularly during outdoor activities, sports lessons, or in poorly ventilated indoor spaces.

Symptoms may include:

• Excessive sweating
  
• Excessive thirst
• Nausea or vomiting
  
• Fatigue or weakness
• Tiredness and dizziness
• Headache or a high temperature
• Muscle cramps in the arms, legs and stomach
• Fast breathing or heartbeat
• Skin becoming pale and clammy (changes in skin colour can be harder to see on brown and black skin)
  
• Getting a heat rash
  

Prompt action is essential to prevent heat exhaustion from progressing to heatstroke. 

What is heatstroke?

Heatstroke is the most serious heat-related condition and should always be treated as a medical emergency. It occurs when the body’s temperature regulation system fails, causing the core body temperature to rise above 40°C.

Warning signs of heatstroke include:

• Still being unwell after 30 minutes of resting in a cool place, being cooled down and drinking fluids
• High body temperature (often 40°C or above)
• Hot or dry skin that is not sweating and might look red (this can be harder to see on brown and black skin)
• Confusion or disorientation
• Rapid breathing or shortness of breath
• Rapid heartbeat
• Seizures or fits
• Loss of consciousness

If heatstroke is suspected, school staff must call 999 immediately.

What school staff can do if a pupil shows signs of dehydration or heat-related illness:

1. Move them to a cool place:

Take the pupil indoors or into shade and encourage them to rest.

2. Encourage fluid intake if possible:

Small, frequent sips of water are best.

3. Cool the body:

If possible, use cool compresses, fans, or damp cloths on the neck, wrists, and forehead.

4. Monitor symptoms closely:

Watch for any signs of deterioration, particularly confusion, vomiting, or loss of consciousness.

5. Seek urgent help if needed:

If heatstroke is suspected, call 999 immediately and continue cooling efforts while waiting for emergency services.

Preventing heat-related illness in schools

Preparation is key when it comes to warm weather safety.

Schools can help reduce risk by:

✅  Encouraging regular water breaks throughout the day

✅ Ensuring pupils have access to drinking water at all times

✅  Scheduling outdoor activities outside peak heat hours where possible

✅  Providing shaded areas for break times and PE lessons

✅  Allowing uniform adjustments during heatwaves where possible

✅  Educating pupils on the importance of hydration

Small, simple adjustments can make a big difference to pupil wellbeing and safety, helping pupils to stay comfortable, safe, and able to make the most of warm weather.

Supporting resources

Below are some guidance sheets on dehydration, heat exhaustion, and heatstroke to share with your colleagues this spring. These resources provide important information on recognising the symptoms of each condition and how to respond effectively in case of an emergency. By familiarising yourself with these resources, you can help ensure the safety and wellbeing of the students in your care during warmer weather.

1. Staff Quick Guide – Dehydration
2. Staff Quick Guide – Heat exhaustion and heatstroke
   
3. Heat exhaustion vs. heatstroke (A4 landscape poster)