The short answer
Check people first and call 999 for anyone hurt. If you smell gas, see fire or the building looks badly damaged, get out using the stairs, not a lift, and don't go back for belongings. If you stay, turn off gas at the meter if you smell it, keep away from damaged wiring and fallen power lines, close the stop tap if pipes have burst, and keep away from damaged walls and glass. Then follow instructions from the emergency services.
Why this matters in the UK
The government's National Risk Register includes a scenario of a conventional missile attack on the UK aimed at infrastructure. It says that even though population centres aren't deliberately targeted in that scenario, civilian deaths are likely and essential services would be affected. This post is about the hours afterwards, if something lands near your home.
The UK has no public guide written for this situation. We've used the closest official advice: US government guidance on explosions (Ready.gov), Sweden's brochure In case of crisis or war, and UK advice on gas, electricity, water and storm damage.
During: take cover first
- If there's an air raid warning, Sweden's brochure says take cover at once in the nearest shelter, cellar or other protected place. Indoors is better than outdoors, ideally in a room without windows.
- If debris is falling, Ready.gov says get under a sturdy table or desk.
- Sweden's brochure says to leave shelter when the all-clear is given. In the UK, wait for instructions from the emergency services, radio or GOV.UK.
The "two walls" rule
You may have read about Ukraine's "two walls" rule: if you can't reach a shelter, put at least two walls between you and the street. A spokesperson for Ukraine's State Emergency Service said in May 2025 that it is "more of a psychological concept", that two walls may not protect you from a direct drone hit or large debris, and that people should use a proper shelter. Treat it as a last resort.
Should I tape the windows?
We found no UK official advice that recommends taping windows. What the guidance we read does say is to keep away from them: UKHSA and Ready.gov say stay away from windows, and Sweden says a room without windows is best.
Step 1: People first
- Call 999 for anyone injured. Emergency calls on a mobile can use any network that's available, so try even if your own network is down (Be Ready).
- Severe bleeding: Sweden's brochure says make sure you're safe, call for help, then press firmly on the wound, ideally with a bunched-up T-shirt or scarf, and keep pressing until paramedics take over.
- If someone is trapped, tell the emergency services where. Ready.gov says not to try to move debris yourself: it can cause more harm.
- If you're trapped, signal with a torch, a whistle or by tapping on pipes. Cover your nose and mouth. Shout only as a last resort, so you don't breathe in dust (Ready.gov).
Step 2: Decide whether to stay or leave
Leave now if there's fire, a smell of gas, or the building looks badly damaged. Ready.gov says:
- leave as soon as it's safe, and don't go back for belongings;
- use the stairs, never a lift, and avoid stairs that look badly damaged;
- stay low if there's smoke;
- once you're safe, text or message your emergency contact, and keep phone calls for emergencies.
Then follow the instructions of the emergency services. They may ask you to leave the area, or to turn off your electricity and water.
Step 3: Gas
If you smell gas, National Gas says:
- Don't smoke or light matches.
- Don't switch electrics on or off, including lights.
- Open doors and windows.
- Turn off the gas at the meter control handle, unless the meter is in a cellar.
- Call the National Gas Emergency Service on 0800 111 999 (free, 24 hours).
Be Ready says your gas shut-off valve is usually next to your gas meter. Find it now, in calm time.
If a gas appliance may be damaged, don't use it until it has been checked. The NHS lists headache, dizziness, feeling sick, tiredness and confusion as signs of carbon monoxide poisoning; go outside and get medical advice if you notice them.
Step 4: Electricity
- Keep away from fallen or hanging power lines. Be Ready says high-voltage electricity can jump gaps without warning. Report damage or a power cut on 105 (03457 643643 in Northern Ireland).
- If wiring inside is damaged, or water is near electrics, switch off at your fuse board's main switch if you can do it safely. Be Ready says never touch an electrical switch while standing in water.
- Unplug appliances that were on, so they aren't damaged when the power comes back (Be Ready).
Step 5: Water
- If pipes have burst, close the stop tap. Be Ready says it's usually inside where the supply comes in, often under the kitchen sink, or outside under a cover near your boundary.
- If the mains supply is cut or looks wrong, use bottled water for drinking and check your water company's website (Be Ready). Our post on making water safe to drink covers boiling, tablets and filters.
Step 6: Glass, walls and the roof
- Broken glass: wear sturdy shoes and gloves before you clear it, and keep children and pets out of the room. Cover broken windows with board or heavy plastic to keep the weather out.
- Damaged walls, chimneys and trees: Be Ready's advice after a storm is not to walk close to walls, buildings and trees that may have been weakened. The same applies after a blast. Keep away from cracked walls and leaning chimneys until someone qualified has looked at them.
- Don't climb onto the roof or do repairs while there's any further danger. Be Ready's storm advice is not to go out to repair damage while the storm is still going on.
Step 7: Record the damage
Be Ready's advice after a flood carries over: take photos or video of all the damage before you clear up, and get your insurer's approval before any repair work. If you're not insured, contact your local council.
Get ready now
- Find your gas meter valve, your stop tap and your fuse board's main switch, and show everyone at home.
- Choose a room without windows, or the most central room, as your shelter room.
- Keep a torch, a whistle, a first aid kit and shoes by the bed or in your go bag.
Frequently asked questions
Should I stay in my house after an explosion nearby?
Stay only if there's no fire, no smell of gas and no obvious structural damage, and follow what the emergency services say. Ready.gov says to leave a damaged building as soon as it's safe, by the stairs, and not to go back for belongings.
What should I do if I smell gas?
Don't smoke or light anything, don't switch electrics on or off, open doors and windows, turn off the gas at the meter control handle (unless the meter is in a cellar) and call the National Gas Emergency Service on 0800 111 999.
Is it safe to touch fallen power lines?
No. Be Ready says keep as far away as possible: high-voltage electricity can jump gaps without warning. Report a power cut or damage on 105 (03457 643643 in Northern Ireland).
What if someone is trapped?
Call 999. Ready.gov says not to try to move debris to rescue people yourself, because moving debris can cause more harm; tell the emergency services where they are. If you're trapped, signal with a torch, a whistle or by tapping on pipes, cover your nose and mouth, and shout only as a last resort.
Sources
We opened each page on the date shown. Official advice changes: if a source says something different now, follow the source.
- Ready.gov (FEMA): Explosions (read 1 November 2026)
- National Gas: Emergency contacts and gas safety advice (read 1 November 2026)
- GOV.UK Be Ready: flooding (turning off gas, electricity and water) (read 1 November 2026)
- GOV.UK Be Ready: storms (after a storm) (read 1 November 2026)
- GOV.UK Be Ready: power cuts (read 1 November 2026)
- GOV.UK Be Ready: water supply interruptions (read 1 November 2026)
- NHS: Carbon monoxide poisoning (read 1 November 2026)
- Swedish Civil Defence and Resilience Agency (MCF): In case of crisis or war, English edition (PDF) (read 1 November 2026)
- Media Center Ukraine: State Emergency Service (SESU/DSNS) briefing, 'Two walls rule doesn't guarantee full protection' (28 May 2025) (read 1 November 2026)
- UKHSA (GOV.UK): What to do in a radiation emergency (keep away from windows) (read 1 November 2026)
- Cabinet Office: National Risk Register 2025 (PDF), 'Conventional attack on the UK mainland or overseas territories' (read 1 November 2026)
Related guides
- How to turn off your gas, electricity and water
- Smell gas? What to do, step by step
- Storm damage to your home: what to do first
- Home first aid kit and medicine cabinet: a UK checklist
We're an independent UK site, not the government. We check guides against official sources and link to them. In an emergency call 999.
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