
Call 999 and say a child or an animal is shut inside a car. Give the location, the registration and how they look. A closed car in sunshine becomes dangerous within minutes, so this is an emergency call.
That is the whole answer, and everything below it is detail. If you are standing at the car right now, make the call first and read the rest while you wait.
What to do in the first sixty seconds
Four things, in this order. The first one is the only one that cannot wait.
Nothing in that list involves getting into the car yourself. That part belongs to the people who arrive, and the reasons why are further down.
Is this a 999 or a 101 call?
Both numbers are correct in different situations, and the difference is distress rather than the type of car or how long it has been.
999 covers anybody or any animal showing signs of trouble. A child who is red, sweating, drowsy or unresponsive. A dog panting heavily, dribbling, weak or lying down. Also any car standing in direct sun with the windows up, whatever state the occupant appears to be in, because the state changes faster than a passer-by can judge.
101 covers a dog in a car on a mild or overcast day with no distress showing, where the concern is real but nothing has gone wrong yet. The RSPCA cruelty line on 0300 1234 999 takes the same reports, though inspectors have no power to force a vehicle open without the police, which is why the charity itself sends urgent cases to 999.
Where you are unsure which of the two applies, it is 999. An operator who decides it is not urgent has lost nothing. A wait that turns out to have been the wrong call cannot be undone.
How fast a parked car becomes dangerous
Faster than almost anybody expects, and the figures are worth knowing before you need them.
Glass behaves like a greenhouse. Sunlight passes in, heat does not pass back out, and the air inside climbs away from the air outside. At 22 degrees outside, the inside of a closed car reaches 47 degrees within an hour. The first part of that climb is the fastest, with a rise of around 10 degrees in the first 10 minutes.
Two beliefs cause most of the harm, and both are wrong.
- Parking in shade does not solve it. Shade moves with the sun, and a car shaded at half past one is in full sun by two
- A window left open does very little. A gap of a few centimetres changes the inside temperature by a couple of degrees, which is nothing against a climb of twenty five
A bowl of water makes no difference either. A dog cools itself by panting, and panting stops working once the air being breathed is hotter than the dog.
What to do while you wait for help
Help is usually a few minutes away rather than seconds, and that gap is the part nobody writes about.
If it is a child. Get to the window where they can see your face and keep talking. A child who can see somebody familiar stops panicking, and a child who is talking back is a child you can report on when the crew arrives. Keep them awake and looking at you. Shade the glass nearest them with a coat, a bag or an umbrella, because blocking direct sun off one window genuinely slows things down.
If it is a dog. Shade the window the dog is lying against and keep somebody paging the driver inside the shop. Note the time you arrived and what the dog was doing then, because that comparison is what tells the crew how quickly it is deteriorating.
For both, stay on the phone if the operator asks you to. They can hear changes in your description that you would not think to report.
A dog shut in a warm car
This is the situation most people find themselves in, standing in a car park beside a car belonging to somebody they have never met, unsure whether they are overreacting.
It splits in two, and the split decides everything. A dog showing signs of distress is an emergency now. A dog that is uncomfortable but coping is a situation to act on without forcing anything.
How to tell a dog is in trouble
Six signs, and any one of them is enough.
- Heavy or frantic panting
- Dribbling or drooling more than usual
- Vomiting or diarrhoea
- Weakness or unsteadiness
- Drowsiness, or lying still instead of reacting to you
- Collapse
Where none of those are showing, the dog is not in immediate trouble and there is time to do this properly. Note the registration, the make and the colour, go into the shop and have the driver paged, and call 101. Stay where you can see the car while all of that happens, because a dog that was fine four minutes ago is the same dog that collapses on minute five.
What the law says about breaking a window
This is the question everybody asks, and the answer circulating online is wrong often enough to be dangerous.
Breaking into a vehicle is criminal damage. There is no general right for a member of the public to force a car open to rescue an animal, and no law that makes it automatically lawful.
What exists instead is a defence. Section 5 of the Criminal Damage Act 1971 allows for damage done where the person genuinely believed the owner would have consented had they known the circumstances. That is a defence raised afterwards rather than a permission granted in advance, and whether it succeeds turns on the facts.
Police guidance on it is consistent and it is worth following exactly.
- Call first. 999 where the dog is distressed, 101 where it is not
- Tell the police what you intend to do and why, before you do anything, and stay on the line
- Photograph or film the dog and the car, including the registration and the conditions
- Take the names and numbers of witnesses who saw the same thing you did
The official wording is that anybody doing this must be ready to justify their actions in court. That is not a scare tactic, it is the legal position, and somebody who has called, described what they are about to do and gathered witnesses is in a very different position from somebody who has not.
The decision is not one this page makes for anybody. What the page does say is that the call comes first, every time, because a crew arriving with the authority to open the car removes the question entirely.
How to cool a dog down safely
Once the dog is out, cooling it down starts immediately and the vet call happens in parallel rather than afterwards.
- Move it into shade
- Lay it on a cool floor or cool ground
- Offer small amounts of water, not a full bowl at once
- Fan cool air over it
- Pour water over its body, starting with the neck and the inner thighs
- Move it into an air-conditioned car once it is stable enough
- Get it to a vet
The vet step is not conditional on how the dog looks. Heatstroke does damage that is not visible, and a dog that seems to recover in the car park still needs seeing.
A child left in another car
The same call applies, with two differences worth knowing.
Do not wait to be certain. A sleeping child looks peaceful, and a child who has stopped crying looks settled. Both are also what a child in trouble looks like. The operator would far rather take a call that turns out to be a parent two minutes away than take one four minutes late.
The law does not work on a stopwatch. There is no age in UK law below which a child cannot be left in a car and above which they can. Under the Children and Young Persons Act 1933 the test is whether the child was left in a way likely to cause unnecessary suffering or injury, which means a short absence on a hot day is treated more seriously than a long one on a cold one.
Page the driver inside the shop while you are waiting. That resolves most of these before anybody arrives, and nobody has lost anything by it having been reported.
When nobody is inside the car
Everything above applies when there is somebody inside. Where the keys are shut in and the car is empty, it is a different situation entirely and the emergency services are not the answer to it.
Fire and rescue services put it plainly. Where there are concerns about a person, call 999. In less urgent circumstances, a locksmith or a breakdown service is the right call. Keys shut in the car with nobody inside is squarely in the second group, whatever time of night it happens.
That includes the awkward middle case, which is a car that has locked itself with the engine running and shopping or a phone inside. Frustrating, expensive in fuel, and not an emergency. A 24 hour call-out covers it at any hour without a fire crew being taken off something that matters.
Why a locksmith is not the fastest option
It is worth being direct about this, because the whole internet on this subject is written by people with a van.
A fire crew is faster and it carries authority a locksmith does not. It is dispatched the moment the call is graded, it travels on blue lights, and it can force entry without anybody having to weigh up the legal position first. A locksmith drives through the same traffic as everybody else and opens the car without damage, which is the right priority for a car with shopping in it and the wrong priority for a car with a child in it.
So the order never changes. Somebody inside, 999. Nobody inside, a locksmith. Anybody telling a parent otherwise is selling something.
How to stop it happening again
Almost every one of these traces back to the same moment, which is a set of keys put down inside the car for two seconds.
Keys stay on you, never on the seat. Not in a bag on the passenger seat, not in a door pocket, and not in the boot while it is being loaded. Keyless cars make this worse rather than better, because the car locks itself and the key is wherever it was left.
Do the back seat check. Before the door shuts, look at the back seat. Every time, including the times you know it is empty. It takes a second and it becomes automatic within a week.
Keep a spare somewhere that is not the car. At home, with a partner, or at work. A second key turns the worst morning of the year into an inconvenience, and spare car keys cost a fraction of what an emergency job does.
Never leave the engine running with a door shut. A running car that locks itself is one of the commonest calls of the summer, and it is the one where a child is most often inside.