If you smell gas, treat it as an emergency. Do not smoke, light a flame or turn electrical switches on or off. Open doors and windows if you can do so quickly, turn the gas off at the meter only if it is safe and the meter is not in a cellar, get people away from the affected area, then call the National Gas Emergency Service on 0800 111 999 from outside or a safe place. The number is free and available 24 hours a day.
Do not spend time trying to identify which appliance is responsible. The emergency service will tell you what to do next.
What should I do immediately if I smell gas?
- Avoid ignition sources. Do not smoke, strike matches or use any flame.
- Do not operate electrical switches. Leave lights and appliances exactly as they are.
- Ventilate if safe. Open doors and windows on your way out.
- Turn off the gas only if safe. Use the meter control valve if you know where it is and can reach it without entering a cellar or dangerous area.
- Move people away. Leave the property if the smell is strong, the source is unclear or you feel unwell.
- Call 0800 111 999. Phone the National Gas Emergency Service from outside or another safe place.
Follow the call handler’s instructions. If there is immediate danger, fire or an explosion, call 999 as well.
Why should I avoid electrical switches?
An electrical switch can create a small spark. That includes turning a light on or off, unplugging equipment, operating a boiler control or using an appliance that may spark. Do not use a doorbell or electrical fan in the affected area.
Leave switches in their current position. Your priority is to get clear and report the smell, not to shut down every device.
Should I open windows and doors?
HSE, National Gas and Cadent all advise opening doors and windows to ventilate the property. Do this only if it is quick and safe; do not delay leaving a strong smell or return to open another window.
Do not switch on an extractor fan. Natural ventilation through already accessible doors and windows avoids operating electrical equipment.
Should I turn the gas off at the meter?
If you know where the gas meter is and can reach it safely, turn the emergency control handle off. National Gas specifically says not to enter a cellar to reach a meter. Cadent also says to evacuate rather than entering a basement where gas may be present.
Do not force a stiff handle, dismantle the meter or touch pipe fittings. Tell the emergency call handler whether you turned the gas off.
Where should I make the emergency call?
Call from outside the affected property or another safe place. The National Gas Emergency Service number for gas or carbon monoxide emergencies in Great Britain is 0800 111 999, available around the clock and free to call.
Give the full address, where the smell is strongest, when it began, whether it is inside or outside, whether the gas is off and whether anyone feels unwell. Mention a cellar, basement, shared building or vulnerable occupant.
What if the smell is outside?
Call 0800 111 999 as soon as possible. Keep away from the strongest-smelling area, prevent flames and smoking nearby, and follow the operator’s advice. Do not search for a damaged pipe or lift covers.
If roadworks or digging may have struck a gas pipe, report it even if no smell is obvious. National Gas says a struck pipeline should be reported immediately.
What if I only smell gas near the boiler?
The response is still the same: avoid switches and flames, ventilate if safe, leave the affected area and call the emergency number. Do not reset the boiler, remove its case or tighten a connection.
A boiler fault code cannot make a suspected leak safe. The source could be the appliance, pipework, meter or another gas fitting and needs competent investigation.
What if I smell gas near the cooker?
Do not operate the cooker controls to test it. If a burner control is visibly in the wrong position and can be turned off without entering danger, follow the emergency call handler’s guidance. Otherwise leave it alone and get out.
Do not light another burner to check whether the supply works. Keep everyone away until the situation has been assessed.
Can I use my phone inside?
The safest approach is to go outside before making the call. Do not charge, plug in or operate devices in the affected area. If leaving requires passing through a dangerous concentration or anyone cannot evacuate, call 999 and follow emergency instructions.
What if someone feels dizzy or sick?
Move into fresh air. Headache, dizziness, nausea, weakness, confusion, chest or muscle pain and shortness of breath can be symptoms of carbon monoxide exposure. Carbon monoxide itself has no smell, so a gas odour is not a reliable test for it.
NHS advice says to call 111 if you think you have symptoms of carbon monoxide poisoning. Call 999 or go to A&E for severe symptoms such as difficulty breathing, sudden confusion, loss of consciousness, weakness or chest pain. Do not go back inside for belongings.
Is a carbon monoxide alarm the same as smelling gas?
No. Natural gas is deliberately odorised so leaks can be noticed; carbon monoxide is colourless and odourless. If a carbon monoxide alarm sounds, get into fresh air, stop using the suspected appliance if this can be done safely and call the National Gas Emergency Service.
Do not dismiss an alarm because you cannot smell anything. Follow the alarm instructions and seek medical advice if anyone has symptoms.
What should tenants do?
Take the same emergency actions and call 0800 111 999 yourself; do not wait for a landlord to report a live smell. Once everyone is safe and the emergency has been reported, tell the landlord or managing agent.
GOV.UK says landlords must keep supplied gas equipment safely installed and maintained by a Gas Safe registered engineer and arrange the required gas safety checks. Emergency safety comes before discussions about responsibility.
What should a landlord do?
Tell the occupant to call the National Gas Emergency Service immediately if they have not already done so. Do not ask them to locate the source, reset a boiler or wait for a routine contractor.
After the emergency service makes the situation safe, arrange any appliance or installation repair with a Gas Safe registered engineer who is qualified for the work. Keep records and provide safe temporary arrangements where required.
What not to do if you smell gas
- Do not smoke, vape, strike matches or light candles.
- Do not turn lights or electrical switches on or off.
- Do not unplug appliances.
- Do not reset or test the boiler.
- Do not search with a flame.
- Do not enter a cellar or basement containing the smell.
- Do not attempt a pipe, meter or appliance repair.
- Do not turn the gas back on yourself after an emergency isolation.
What happens after I call?
The call handler will give immediate safety advice and gather details. The gas emergency service may attend to locate the escape and make the situation safe. That may involve isolating the supply or an appliance.
Making safe is not always the same as completing the appliance repair. If a boiler or other appliance is identified, a suitably qualified Gas Safe registered engineer may be needed before it can be used again.
When can I use the gas again?
Do not restore a supply or use an isolated appliance until the emergency service or a competent Gas Safe registered engineer says it is safe. HSE states that an appliance suspected of being unsafe must be turned off and not used until checked.
Never remove a warning label or reconnect an appliance yourself.
Frequently asked questions
Who do I call if I smell gas in Leeds?
Call the National Gas Emergency Service on 0800 111 999 from outside or another safe place. The number covers Great Britain and is free 24 hours a day.
Should I call my boiler company first?
No. Report a suspected gas leak to 0800 111 999 first. Boiler repair comes after the emergency has been made safe.
Is a faint smell still worth reporting?
Yes. Do not decide that a smell is too slight to matter. The emergency service can assess the report and advise you.
Can I turn the boiler off?
Do not operate electrical or appliance controls in the affected area. Leave and follow the emergency call handler’s advice.
Keep the emergency number saved, but never delay leaving a dangerous area to find a phone or take photographs. Your immediate safety comes first.
Related boiler-help guides
- What to do when a carbon monoxide alarm sounds
- Unusual smells from a boiler
- What happens if a boiler is made safe or condemned?
Has the gas emergency service made the property safe?
Once the emergency has been dealt with, book a fixed-price Incredaboil boiler repair if the appliance still needs professional attention.