At the Scene of an Incident

The first two minutes after a collision decide how safe everyone stays. Learn the stop-warn-help sequence, what you're required to exchange, and the 24-hour rule if you can't.

Provisional licenceAll UK nations
⏱️ About 12 min

Most drivers never plan for the moment a collision happens right in front of them, or to them. But the first minute afterwards follows a simple, repeatable order: make it safe, warn others, then help. Learn that order now and you won't have to invent it under pressure.

💡
The big idea: At any incident, safety comes before paperwork: stop, protect the scene with hazard lights and warning, then call for help. Only once that's done do you deal with exchanging details — and there's a legal fallback if you can't do it at the roadside.
🎯 By the end, you'll be able to
  • State what you must do immediately if you're involved in a collision that injures someone or damages another vehicle, animal, or property
  • List the details you're required to exchange with anyone else involved
  • Explain the 24-hour rule for reporting to the police when details can't be exchanged at the scene
  • Recognise a dangerous-goods (hazchem) plate on a lorry and know why it matters to emergency services

Stop — it isn't optional

If you're involved in an incident that injures another person or animal, or damages another vehicle or property, you're required to stop. Pull off the road if you safely can — onto a hard shoulder, verge, side road, or car park — rather than leaving vehicles blocking a live lane. If you can't move the vehicles at all, put the safety of everyone outside a vehicle first: get people onto the verge or footway, well away from moving traffic, before anything else.

🔑 Make the scene visible before you do anything else

As soon as you've stopped, switch on your hazard warning lights so approaching traffic sees trouble ahead. If you have a warning triangle and it's safe to place one — never on a motorway — set it back down the road to give other drivers extra notice. The goal in these first seconds is simple: make sure nobody else drives into the scene you're already dealing with.

Call for help when it's needed

Call 999 (or 112, which reaches the same emergency services) whenever anyone is injured, a vehicle is blocking the road or creating a danger, or you suspect a fire, fuel leak, or damage to things like a gas main or overhead power line. Give the call handler your location as precisely as you can — a road name and direction of travel, or, on a motorway, the last driver location sign or marker post you passed — plus how many people and vehicles are involved and what kind of help sounds needed (ambulance, fire, police).

What you're required to exchange

If another person is involved — another driver, a cyclist, or someone whose property was damaged — you must give them your name and address, the vehicle owner's name and address if different, and the vehicle's registration number. If someone reasonably asks to see it, you must also show your insurance certificate; if you can't produce it on the spot, you can be asked to take it to a police station within a set number of days instead.

⚠️ Can't exchange details? You must report it within 24 hours

If there's nobody around to exchange details with — say you've clipped a parked car and the owner isn't there — you're still required to report the incident to the police, and to do it as soon as reasonably practicable, and in any case within 24 hours. Leaving a note on the windscreen is good practice, but it does not replace this reporting duty.

Casualties: help without making things worse

Keep any casualties out of the roadway if you can move them without risk, but as a general rule don't move an injured person unless leaving them where they are puts them in further danger — for example, a vehicle on fire or on an unstable slope. Moving someone with an unknown injury, especially to the neck or back, can make it worse. Keep them still, keep them calm, and keep other traffic well clear until trained help arrives — the next lesson covers what you can safely do while you wait.

Dangerous-goods plates: why a lorry's markings matter here

Lorries carrying hazardous substances — fuel, chemicals, gases — display an orange hazchem plate on the vehicle, often with a hazard warning diamond alongside it showing a code and symbol for the substance. If a lorry like this is involved in an incident, keep well back and upwind if you can, don't use anything that could spark, and pass on exactly what the plate shows when you call for help — the emergency services use those codes to know what they're dealing with before they even arrive.

Check your understanding

1. You've just been in a minor collision on a quiet road and nobody is hurt. What should you do first?
Stopping is required whenever a collision injures someone or damages a vehicle, animal, or property. Clear the road first if it's safe to do so, so you're not creating a second hazard.
2. You've stopped after a collision. What's the first thing you should switch on?
Hazard warning lights make the scene visible to approaching traffic in every direction, before you do anything else.
3. You reverse into a parked car in a car park and the owner isn't there. What must you do?
When you can't exchange details at the scene, you're still required to report the incident to the police within 24 hours. A note is good practice, but it doesn't replace that duty.
4. A lorry with an orange hazchem plate is involved in a breakdown ahead of you. What should you do?
A hazchem plate warns that the load may be dangerous. Keep your distance and relay the plate's details to the emergency services so they know what they're responding to.
🔎 Related lessons
Next: First Aid on the Road (DR ABC) Breakdowns, Fires & Tunnel Emergencies
✅ Key takeaways
  • Stop whenever a collision injures someone or damages another vehicle, animal, or property — clear the road first if it's safe.
  • Hazard lights on immediately; a warning triangle helps too, but never place one on a motorway.
  • Call 999/112 for injury, danger, or blocked roads, and give your location as precisely as you can.
  • Exchange name, address, and vehicle registration; if you can't, you must report to the police within 24 hours.
  • Don't move a casualty unless staying put puts them in further danger — and keep well back from vehicles carrying a hazchem plate.
➡️ You now know how to make a scene safe and get help on the way. Next: what you can actually do for an injured person in those first few minutes, using the same simple order every time — DR ABC.

Frequently asked questions

Do I have to stop if I'm involved in a road accident in the UK?
Yes — you must stop if the incident injures a person or animal, or damages another vehicle or property, even if the damage looks minor.
What details do I have to give after a collision?
Your name and address, the vehicle owner's name and address if different, and the vehicle registration number, to anyone with reasonable grounds to ask for them.
What happens if I can't exchange details at the scene?
You must report the incident to the police as soon as reasonably practicable, and in any case within 24 hours — leaving a note is good practice but doesn't replace this duty.
Ready to check how you'd do?

You've learned the material free. Put it to the test with our practice exam — hundreds of exam-style questions with instant explanations, in a realistic format.

Try the UK Theory Practice Test →

Independent educational content — not affiliated with, endorsed by, or connected to the DVSA, DVLA, or any government body. This is study material, not legal advice; always confirm current rules in the official Highway Code.