Smell Gas in Your Home? What to Do Immediately

The short answer: ventilate, avoid sparks and call

If you smell gas in your house, treat it as an emergency. In Great Britain, open doors and windows, avoid flames and electrical switches, turn the gas off at the meter only if you know how and it is safe to reach, then call the National Gas Emergency Service on 0800 111 999. In Northern Ireland, call 0800 002 001. Both services are available 24 hours a day.

Do not spend time trying to identify which appliance or pipe caused the smell. Natural gas is given a distinctive odour so a possible escape can be noticed quickly. The safe response is to reduce ignition risks, get fresh air through the property and report the suspected leak.

Open doors and windows if you can do so safely. Do not smoke, strike a match, use a lighter or turn an electrical switch on or off. That includes lights, sockets, extractor fans, thermostats, doorbells and appliance controls. Call from outside or away from the smell when possible. If there is immediate danger, a fire, an explosion or someone is seriously unwell, leave and call 999.

Follow this gas-leak checklist

The emergency operator will ask for the address and details of the smell, including where it is strongest and when it began. Mention any cellar or basement, neighbours who may be affected, vulnerable people, access needs and any damage to a gas pipe. Give clear information and follow the operator’s instructions rather than returning indoors to investigate.

Do not turn the gas back on or use a suspect appliance until the emergency service or a suitably qualified Gas Safe registered engineer says it is safe. The smell fading after ventilation does not prove that the fault has gone.

• Move away: keep people away from the affected area and go outside if the smell is strong, persistent or widespread.
• Avoid ignition: do not smoke, use a naked flame, operate a switch or unplug electrical equipment.
• Ventilate: open doors and windows if this can be done safely and without delaying your exit.
• Isolate only if safe: turn off the gas at the meter only if you know where the control is and can reach it safely; never enter a cellar to do this.
• Call: use 0800 111 999 in Great Britain or 0800 002 001 in Northern Ireland, then follow the operator’s instructions.

Should you turn off the gas at the meter?

Only approach the meter if it is safe, accessible and you already know where it is. The emergency control valve is normally beside the gas meter. Do not force a stuck control or use tools. If you are uncertain, leave it alone and tell the emergency operator.

Do not enter a cellar or basement to reach a meter when gas may have collected there. National Gas specifically says not to turn off a meter in a cellar. If the meter, pipework or valve looks damaged, do not touch it.

After isolation, do not turn the supply back on yourself. Appliances may need to be checked and safely relit. The emergency service will explain the next step, which may involve the gas network, your landlord, your supplier or a Gas Safe registered engineer depending on where the fault is. If you do not know your meter location, our gas meter guide explains common types and positions for a calm, non-emergency check later.

Gas smell and carbon monoxide are different warnings

Mains gas has an added smell that helps people notice an escape. Carbon monoxide does not: the NHS describes it as colourless and odourless. A home can therefore have a carbon monoxide problem without any gas smell.

Possible carbon monoxide symptoms include headache, dizziness, nausea or vomiting, weakness, unusual tiredness or confusion, chest or muscle pain and shortness of breath. Symptoms may improve outside and return in the building. If you suspect carbon monoxide, stop using the possible source if you can do so safely, go outside and get medical advice promptly. The NHS says to call 111 for suspected symptoms and 999 or go to A&E for serious symptoms including difficulty breathing, sudden confusion, loss of consciousness, weakness, or chest or muscle pain.

A sounding carbon monoxide alarm is a reason to leave and act, not to search for the source. Call the gas emergency service for a suspected gas-appliance carbon monoxide emergency. A carbon monoxide alarm is an extra precaution, not a substitute for correct installation, maintenance and servicing. See our gas boiler service guide for planned maintenance after the immediate risk has been dealt with.

What happens after the emergency call?

The emergency service’s first job is to make the situation safe. The attending engineer may check for gas, isolate the supply or an appliance, and explain what must happen before it can be used again. An emergency response does not necessarily include repairing an appliance or internal pipework.

If an appliance is labelled or disconnected as unsafe, do not reconnect it. Arrange any repair through a Gas Safe registered engineer qualified for that appliance. Check the engineer’s ID card and work categories. Tenants should tell the landlord or managing agent after making the emergency call; do not wait for a landlord’s office to open before reporting a suspected leak.

Tell the emergency operator about anyone who may need additional help. Eligible households in Great Britain can also record ongoing communication and support needs on the Priority Services Register; Northern Ireland uses customer-care registers. Registration does not replace the emergency call.

Keep the emergency visit record and any warning notice. Once the property is safe, take a meter reading only if advised and accessible, then check later bills for unusual estimated use. The gas bill calculator can compare two safe, normal meter readings, but it must never delay an emergency call.

Use the correct number for your part of the UK

For England, Scotland and Wales, the free National Gas Emergency Service number is 0800 111 999. It operates 24 hours a day and is the correct first call for a smell of mains gas, a suspected gas escape, a gas-related carbon monoxide emergency or a struck gas pipe.

Northern Ireland has its own 24-hour gas emergency line: 0800 002 001. The Utility Regulator says to use this number regardless of supplier. Supplier customer-service numbers are for accounts and billing, not the immediate emergency response.

For bottled gas or LPG, use the emergency instructions from the cylinder or tank supplier. If there is immediate danger, move away and call 999.