Hypothermia first aid focuses on preventing further heat loss, getting the casualty somewhere sheltered, replacing wet clothing with dry insulation and getting medical help. Hypothermia occurs when the body’s temperature falls dangerously low and it can become life-threatening.

It is often associated with freezing winter weather, but hypothermia can develop in less extreme conditions too.

Cold wind, wet clothing, immersion in cold water, exhaustion and prolonged exposure can all contribute.

If you think someone has hypothermia, treat it seriously and get medical help.

What Is Hypothermia?

Hypothermia is a dangerous drop in body temperature.

Normal body temperature is around 37°C. The NHS defines hypothermia as a body temperature below 35°C.

As the body cools, its normal functions begin to slow down.

This can affect:

the brain
breathing
circulation
coordination
judgement
consciousness
eventually, the heart

Hypothermia is therefore more than simply feeling very cold.

It is a medical emergency.

What Causes Hypothermia?

Hypothermia develops when the body loses heat faster than it can produce it.

Common causes include:

staying outside in cold weather for too long
inadequate clothing
wet clothing
falling into cold water
cold and windy conditions
prolonged exposure after an accident
living in a very cold home
exhaustion during outdoor activities

The risk is not determined by air temperature alone.

Wet clothing and wind can significantly increase heat loss.

Someone who becomes injured outdoors may also be particularly vulnerable because they are unable to keep moving or reach shelter.

What Are the Symptoms of Hypothermia?

Possible symptoms include:

shivering
cold skin
pale skin
blue or grey lips or skin
slurred speech
slow breathing
tiredness
confusion

As hypothermia becomes more severe, the casualty may become increasingly confused, drowsy or unresponsive.

Shivering may also reduce or stop as their condition becomes more serious.

Do not assume that somebody who has stopped shivering is getting warmer.

In a severely cold casualty, stopping shivering can be a warning sign.

Recognising Hypothermia in Different Skin Tones

Changes in skin colour can sometimes be more difficult to recognise depending on the casualty’s skin tone.

The NHS notes that blue or grey colour changes may be easier to see on the palms of the hands or soles of the feet in someone with black or brown skin.

Do not rely on skin colour alone.

Look at the whole casualty and consider symptoms such as:

shivering
cold skin
slurred speech
confusion
drowsiness
abnormal breathing
reduced responsiveness

Hypothermia First Aid: What Should You Do?

If you suspect hypothermia:

Call 999 or arrange urgent medical help.
Move the casualty somewhere sheltered if this can be done safely.
Protect them from wind and further cold exposure.
Remove wet clothing gently.
Replace wet clothing with dry clothing, blankets or a sleeping bag.
Cover their head.
Insulate them from the cold ground.
Give a warm non-alcoholic drink and sugary food only if they are fully awake and can swallow safely.
Stay with them and monitor their condition.

Avoid unnecessary handling, particularly if the casualty appears seriously affected.

Call 999 for Suspected Hypothermia

The NHS advises getting emergency medical help if you think someone has hypothermia.

Call 999 and ask for an ambulance if necessary.

Do not assume you can simply warm someone up and then send them home.

A significantly hypothermic casualty may need hospital assessment and treatment.

Tell the ambulance service:

what happened
how long the casualty may have been exposed
whether they became wet or were immersed in water
their current condition
whether their responsiveness or breathing has changed

Follow the call handler’s instructions.

Move the Casualty Somewhere Sheltered

Preventing further heat loss is an important part of hypothermia first aid.

Where possible, move the casualty:

indoors
into a vehicle
into a tent or shelter
behind an effective windbreak
somewhere protected from rain, snow and wind

However, do not put yourself in danger trying to move someone from a hazardous location.

Call the emergency services if specialist rescue is required.

Remove Wet Clothing

Wet clothing can continue drawing heat away from the body.

If possible, gently remove wet clothing and replace it with:

dry clothing
blankets
towels
a sleeping bag
other suitable dry insulation

Protect the casualty from further exposure while doing this.

Avoid leaving them unnecessarily exposed while changing clothing.

Insulate the Casualty from the Ground

Heat can be lost through direct contact with a cold surface.

Do not simply wrap the top of the casualty while leaving them lying directly on cold ground.

Place suitable insulation underneath them where possible.

This might include:

blankets
sleeping mats
dry clothing
foam pads
other insulating materials

Current Resuscitation Council UK guidance specifically identifies ground isolation as part of preventing hypothermia.

Protect Them from the Wind

Wind can increase heat loss significantly.

Use available shelter or barriers to protect the casualty.

This might mean:

moving behind a wall
entering a shelter
using a tent
using a vehicle
creating a windbreak

Combine wind protection with dry insulation.

Should You Give Someone with Hypothermia a Hot Drink?

The NHS recommends a warm, non-alcoholic drink if the casualty is fully awake.

They may also be given sugary food, such as chocolate, if they are fully alert and able to eat safely.

Do not give food or drink to somebody who:

is significantly drowsy
is confused and cannot safely swallow
is becoming unresponsive
cannot protect their own airway

Never give alcohol.

Why Shouldn’t You Give Alcohol?

Alcohol can make someone feel warmer because blood vessels near the skin widen.

However, this can increase heat loss.

Alcohol can also impair judgement and affect someone’s ability to recognise how seriously cold they have become.

The NHS specifically advises not giving alcohol to someone with hypothermia.

Should You Put Someone with Hypothermia in a Hot Bath?

No.

Do not suddenly place someone with hypothermia into a hot bath or shower.

The NHS also advises against using:

hot water bottles
heat lamps

The aim for a first aider is to prevent further heat loss and allow safe rewarming while professional medical help is arranged.

Do not try to heat the casualty aggressively.

Should You Rub Their Arms and Legs?

No.

Do not vigorously rub or massage the casualty’s:

hands
feet
arms
legs

The NHS specifically advises against rubbing the limbs of someone with hypothermia.

Handle the casualty gently.

What If the Casualty Is Unresponsive?

An unresponsive hypothermic casualty requires urgent medical help.

Call 999 if this has not already been done.

Assess their breathing carefully.

Severe hypothermia can cause breathing and circulation to become extremely slow.

Current Resuscitation Council UK guidance advises healthcare and rescue responders to check for vital signs for up to one minute in an unconscious hypothermic casualty because they can be difficult to detect.

For a first aider, the priority is to call 999 promptly, follow the ambulance service’s instructions and be prepared to provide resuscitation if required.

What If Someone with Hypothermia Stops Breathing Normally?

If the casualty is unresponsive and you believe they are not breathing normally, follow the instructions of the ambulance service and begin CPR when indicated.

Use an AED if one is available and follow its prompts.

Do not assume somebody cannot survive simply because they are extremely cold and appear lifeless.

Severe hypothermia can produce very slow vital signs, and specialist resuscitation and rewarming techniques may be possible.

Continue following emergency service instructions until professional help takes over.

Our Basic Life Support guide explains the general principles of recognising cardiac arrest, CPR and AED use.

You can also read our Seven Steps of CPR guide.

Mild, Moderate and Severe Hypothermia

Hypothermia becomes increasingly dangerous as body temperature falls.

Current Resuscitation Council UK specialist guidance uses stages to help assess accidental hypothermia.

Mild Hypothermia

A casualty may still be:

conscious
alert
shivering

The estimated core temperature may be around 35°C to 32°C.

Moderate Hypothermia

The casualty’s consciousness may become impaired.

They may develop:

confusion
lethargy
reduced coordination

Shivering may reduce or stop.

The estimated core temperature may be around 32°C to 28°C.

Severe Hypothermia

At lower temperatures, the casualty may become unconscious and their breathing and circulation can become extremely slow.

This is a life-threatening emergency requiring specialist medical treatment and controlled rewarming.

Members of the public should not delay calling 999 while trying to determine a precise stage or temperature.

Can You Measure Someone’s Temperature?

A normal household thermometer may not be capable of accurately measuring very low core temperatures.

Specialist medical teams use appropriate low-reading equipment and suitable core-temperature measurement techniques.

Do not delay treatment while repeatedly trying to obtain a temperature.

If the casualty has been exposed to cold and has symptoms consistent with hypothermia, get medical help and begin preventing further heat loss.

Hypothermia After Falling into Cold Water

Cold-water immersion can cause several serious problems.

A casualty removed from cold water may continue to be at risk from:

breathing problems
drowning complications
hypothermia
reduced consciousness
cardiac arrest

Get emergency medical help.

Once the casualty has been removed from the water safely:

protect them from wind
remove wet clothing where appropriate
dry and insulate them
keep them off the cold ground
monitor responsiveness and breathing

Never put yourself at risk by entering dangerous water to attempt a rescue.

Our guide to the different types of drowning explains why someone rescued from water may still need urgent assessment.

Hypothermia in Babies and Children

Babies and young children can lose heat quickly.

The NHS advises that a baby with hypothermia may be:

cold to touch
floppy
unusually quiet
sleepy
unwilling to feed

Do not wait for obvious shivering.

If you think a baby or child has hypothermia, get urgent medical help.

Keep them dry, protected from the cold and appropriately insulated while waiting for assistance.

Parents, carers and people working with children can learn how to recognise and manage emergencies through practical Paediatric First Aid training.

Hypothermia First Aid Training Guide. Symptoms, Treatment and How to Keep Someone Warm

Who Is Most at Risk of Hypothermia?

Anyone exposed to cold conditions can become hypothermic.

Some people may be particularly vulnerable, including:

babies
young children
older people
people with certain health conditions
people living in inadequately heated homes
people who are wet
people who are exhausted
people affected by alcohol or drugs
outdoor workers
walkers and hikers
climbers
people participating in outdoor sport
people who have fallen into cold water

Someone who is injured and unable to move may also cool much more quickly than expected.

Hypothermia Can Happen Indoors

Hypothermia is not exclusively an outdoor emergency.

Someone can become dangerously cold inside an inadequately heated home.

Older or vulnerable people may be particularly at risk.

Signs such as:

confusion
unusual drowsiness
slurred speech
cold skin
slow breathing

should not simply be dismissed as tiredness or old age.

Consider the environment and get medical help if hypothermia is suspected.

Hypothermia in the Workplace

Some jobs expose workers to cold, wet or windy conditions.

These may include:

construction
agriculture
maritime work
outdoor maintenance
utilities
forestry
security
events
delivery work
other outdoor occupations

Employers should consider environmental exposure as part of their risk assessment.

Controls might include:

appropriate protective clothing
waterproof clothing
warm rest areas
suitable breaks
access to warm drinks
monitoring weather conditions
changing wet clothing
emergency arrangements
suitable first aid provision

Our guide to the legal requirement for first aid at work explains how workplace risks should influence first aid arrangements.

Preventing Hypothermia Outdoors

Prevention is much easier than treating a casualty who has become seriously cold.

Before outdoor activity:

check the weather forecast
wear suitable layers
carry waterproof clothing
take spare dry clothing
protect the head and extremities
carry emergency shelter where appropriate
take enough food and drink
plan the route
tell someone where you are going
carry suitable communication equipment

Adapt your equipment and planning to the environment and activity.

Why Wet Clothing Matters

Water conducts heat away from the body much more effectively than dry air.

This means a person who becomes soaked can cool rapidly, particularly when wind is also present.

Someone does not need to be standing in snow to develop hypothermia.

A combination of:

cold + wind + rain + exhaustion

can create a significant risk.

This is particularly important during outdoor activities and outdoor work in the UK.

Hypothermia and First Aid After an Injury

Preventing heat loss is important when treating an injured casualty outdoors, even when hypothermia was not the original problem.

Someone who is:

bleeding
injured
lying still
exhausted
wet
exposed to wind

can cool rapidly.

Once immediate life-threatening problems have been managed, protect the casualty from the environment.

Use dry insulation above and below them and provide shelter from wind and rain.

Hypothermia First Aid: What Not to Do

If you suspect hypothermia:

DO NOT use a hot bath.

DO NOT use a hot water bottle directly to rapidly heat them.

DO NOT use a heat lamp.

DO NOT rub their hands, feet, arms or legs.

DO NOT give them alcohol.

DO NOT give food or drink if they cannot swallow safely.

DO NOT leave them alone.

DO NOT assume that stopping shivering means they are getting better.

Instead, prevent further heat loss, handle them gently, get medical help and monitor their condition.

Hypothermia First Aid: What to Remember

The main hypothermia first aid principles are:

GET HELP

Hypothermia is a medical emergency. Call 999 or arrange urgent medical help.

GET THEM SHELTERED

Move them indoors or somewhere protected from the weather where possible.

REMOVE WET CLOTHING

Gently replace wet clothing with dry clothing and insulation.

KEEP THEM INSULATED

Use blankets, towels, sleeping bags or dry clothing.

Remember to insulate them from the cold ground and cover their head.

WARM DRINKS ONLY WHEN SAFE

A fully awake casualty may have a warm non-alcoholic drink and sugary food.

NO DIRECT INTENSE HEAT

Do not use a hot bath, hot water bottle or heat lamp.

HANDLE THEM GENTLY

Do not rub or massage their arms and legs.

MONITOR THEM

Stay with the casualty and watch their responsiveness and breathing until professional help arrives.

For further public guidance, read the NHS information about hypothermia.

The Resuscitation Council UK First Aid Guidelines also provide current guidance on preventing hypothermia, including dry insulation, wind protection, removal of wet clothing and insulation from cold ground.

Learn How to Deal with Medical Emergencies

Knowing hypothermia first aid is particularly valuable for people who work or spend time outdoors, but recognising environmental emergencies forms only one part of good first aid.

Practical training helps you develop the confidence to assess a casualty, recognise deterioration and take appropriate action while professional help is on the way.

First Aid and Safety Training provides:

We provide practical first aid training for individuals and organisations across the North East.

Explore our first aid training across the North East or contact First Aid and Safety Training to discuss the right course for you or your organisation.

You can also see our South Shields training centre and customer reviews on Google Maps.

Real Skills, Real Confidence.