Gas Leaks: What to Do, What Not to Do, and How to Keep Your Home Safe
A gas leak in your home can be fatal within minutes if you make the wrong choices. Knowing exactly what to do and what not to do before you ever smell gas is the knowledge that protects your family.
What a Gas Leak Actually Is
Natural gas in the UK is odourless in its natural state. A chemical called mercaptan is added specifically to give it the distinctive smell most people describe as rotten eggs or sulphur. This additive exists for one reason: to make gas leaks detectable by smell before the gas reaches a dangerous concentration.
Gas leaks occur when natural gas escapes from the pipework, appliances, or connections in your home. This can happen because of a faulty appliance, a corroded or damaged pipe, a connection that has not been made properly, or physical damage to gas infrastructure. Even a small leak can create a dangerous situation if gas accumulates in an enclosed space, because natural gas is highly flammable and can explode when ignited by a spark, a flame, or even a light switch.
Recognising a Gas Leak
The most obvious sign of a gas leak is the smell of rotten eggs or sulphur inside your home, particularly when it cannot be explained by cooking or other known sources. Other signs include a hissing sound near a gas appliance or pipe, dead or discoloured patches of grass or plants over buried gas pipes in the garden, and bubbles in puddles or wet ground near gas pipe routes.
Some people are less sensitive to the smell of mercaptan than others, and a very small leak may not produce a smell strong enough to be immediately obvious. This is one of the reasons regular servicing of gas appliances matters: a Gas Safe registered engineer checks connections and appliances that may be developing faults before they become dangerous.
If you suspect a gas leak but cannot smell it strongly, trust your instinct. The actions described below are appropriate whether you are certain there is a leak or simply concerned that there might be.
What to Do Immediately
If you smell gas or suspect a leak, act immediately. Do not delay to investigate, do not finish what you are doing, and do not wait to see if the smell gets stronger.
Get everyone (including pets) out of the building now. Do not stop to collect belongings. Open windows and doors as you leave if you can do so without delay, to help disperse the gas, but do not go back in if you have already left.
Once outside, call the National Gas Emergency Service on 0800 111 999. This line is free, operates 24 hours a day, 365 days a year, and should be your first call. They will give you immediate advice and arrange for an engineer to attend.
Do not re-enter the building until the emergency service has confirmed it is safe to do so. Do not make or receive phone calls inside the building; use your mobile phone once you are outside.
What Not to Do: The Mistakes That Kill
There are specific actions that can turn a gas leak into an explosion or fire, and understanding them is as important as knowing what to do correctly.
Do not turn any electrical switches on or off. This includes light switches, appliance switches, extractor fans, and anything else electrical. The spark created when an electrical circuit is made or broken can be enough to ignite accumulated gas.
Do not use any naked flames. No candles, no lighters, no matches. Do not smoke inside or immediately outside the building.
Do not use any electrical appliances, including phones that are plugged in, doorbells, or intercoms.
Do not attempt to find the leak yourself. Do not attempt to repair anything. The emergency service will send a qualified engineer who has the training and equipment to do this safely.
Do not turn the gas off at the meter unless you have been specifically advised to do so by the emergency service operator and you can access the meter without entering a confined space where gas may have accumulated.
Preventing Gas Leaks
The most important preventive measure is an annual gas safety check carried out by a Gas Safe registered engineer. All gas appliances in your home, including boilers, gas cookers, gas fires, and gas hobs, should be included in this annual service. The engineer checks appliances, flues, and connections for safety and efficiency, identifying potential problems before they become dangerous.
If you rent your home, your landlord is legally required to arrange an annual gas safety check by a Gas Safe registered engineer and to provide you with a copy of the gas safety record within 28 days of the check. If you have not received one, request it. If your landlord fails to arrange gas safety checks, this can be reported to the Health and Safety Executive.
Always use a Gas Safe registered engineer for any work on gas appliances, pipes, or connections. Do not use unregistered tradespeople for gas work; this is illegal as well as dangerous. You can verify whether an engineer is Gas Safe registered at the Gas Safe Register website or by asking to see their Gas Safe ID card.