Gas leaks are becoming increasingly common in the UK, most likely because of ageing pipes and wear and tear. There are some 31 domestic gas explosions a year on average, but many are preventable.
If you smell gas or suspect a gas leak, call the National Gas Emergency Service immediately on 0800 111 999.
This guide will cover gas leaks in detail, including how to detect and prevent them.
What is a gas leak?
A gas leak occurs when gas (typically natural gas, which is primarily methane, but also liquified petroleum gas, or LPG) leaks from appliances, pipelines or other gas-using devices. Gas leaks can be subtle, with a faint rotten egg smell, but they should never be ignored.
A serious or sustained gas leak can cause nausea and lightheadedness if you’re exposed for long enough. Gas is extremely flammable, and a high concentration in the atmosphere is at risk of ignition or explosion if exposed to sparks or a naked flame. The likelihood of explosion increases when gas is concentrated in a small space, like a kitchen.
Many causes of gas leaks result from human error, e.g. leaving gas burners on when the flame is turned off.
In any case, gas leaks pose a risk of fire and explosion risk if left unchecked, which is why it’s essential to take no chances with any gas leak.
What are the dangers of gas leaks?
In the worst-case scenario, gas leaks can cause fatal explosions. For example, 12 people died from domestic gas explosions between 2017 and 2022, and over 150 were injured.
If you catch a gas leak early, you should be able to avert danger. However, this depends on timely intervention. Never take risks if you smell gas and fear a gas leak.
Fire
Gas leaks can mix with air and create an explosive mixture that ignites easily when exposed to naked flames or sparks. Gas fires aren’t easy to put out and are at high risk of causing explosions.
Explosions
When gas and air mix in a confined space, the pressure increases, which increases the likelihood of a gas explosion. This is particularly common when gas leaks into a small room, such as a kitchen.
Environmental pollution
Some gases, such as methane, which is present in domestic gas, are potent greenhouse gases that can contribute to global warming and climate change if released into the atmosphere.
What are the common causes of gas leaks?
A few things can cause gas leaks, but they’re most likely to be caused by human error, faulty appliances and wear and tear to pipes or equipment.
Here are some leading causes of gas leaks:
Faulty appliances
In domestic properties, faulty cookers are one of the leading causes of gas leaks. For example, if the knobs aren’t turned all the way off, or there’s an obstruction, the cooker may continually leak gas into the room. Alternatively, there might be an issue with the pipes feeding the burners.
This also extends to poor or faulty installations. Gas appliances, such as boilers, should be installed and signed off by Gas Safe-registered engineers.
Boiler faults
Faults in and around the boiler can cause gas leaks. For example, faulty pilot lights may leak gas if the safety shut-off valve fails, though this is rare. Other boiler-related gas leaks may be caused by a fault in the boiler or the neighbouring pipework.
Boilers may smell of gas if they’re dusty, as the dust is burned away, which creates a gas-like smell.
Damaged pipes
The UK’s gas network is ageing, which is leading to increases in gas leaks from corroded or broken pipes.
So if you smell gas somewhere you don’t expect, like the front or back of your house, then the cause may be a broken pipe laid beneath the ground.
Human error
Leaving gas burners on is one of the most common causes of gas leaks.
If the gas feeding the burner isn’t shut off correctly, it can release gas at an alarming rate.
How can I detect a gas leak in my home?
Unlike carbon monoxide, which has no scent, natural gas is pretty smelly. The smell is typically described as a rotten egg smell. Gas leaks are nearly always detectable via scent.
We’re likely all familiar with the smell of gas, which is the first sign of a gas leak.
Smell
Gas smells like rotten eggs. It has a very recognisable smell that most are familiar with. When you leave a burner on by accident, the first thing you’ll probably notice is the smell of gas.
However, the smell of gas can pop up in other places too. For example, you might smell it outside, signalling a potential gas leak in your or your neighbour’s pipes.
Hissing or whistling sound
Gas escaping at high pressure can cause a whistling noise. This is common when the gas is escaping from a high-pressure pipe.
Gas detector
Gas leak detectors work similarly to carbon monoxide monitors. They’re relatively cheap, can be fitted to walls, etc, and will sound upon detecting various combustible gases.
What should I do if I suspect a gas leak?
If you suspect a gas leak, ensure your gas burners and any other fuel-burning appliances are turned off. This is one of the most common causes of a gas leak. If this is the culprit, open all of your windows and step outside the home until it’s adequately ventilated.
Here’s what to do if you suspect a gas leak:
Shut the gas off
National Gas recommends you shut your gas off if you can. Of course, if it’s dangerous or unreasonable to do so, then simply proceed to vacate the home.
Vacate home
Vacate your home immediately if a burner isn’t the cause of the leak and you can’t seem to shut the gas leak off. Sustained gas leaks aren’t just a fire and explosion risk; they can also cause nausea, lightheadedness, fainting and loss of consciousness.
Alert your close neighbours so they can do the same.
Do not turn on or off any lights or appliances, and do not use matches, lighters, or any other open flames
Gas will only catch fire or explode if it’s exposed to a flame or heat source. If you smell gas, never operate a lighter, match or electronic spark device. That includes vehicle spark plugs.
You should also avoid operating light switches or electrical appliances of any kind, including those that use batteries like torches.
Call your gas company or emergency services
If you suspect a gas leak, call the National Gas Emergency Service immediately on 0800 111 999. This free number is available 24/7. They will advise you and may call other emergency services.
If the gas leak has already caused a fire or explosion, dial 999 immediately. Call for an ambulance if you’re experiencing the effects of gas inhalation.
Can gas leaks be prevented?
You can certainly reduce the risk of gas leaks occurring. Human error is a leading cause of gas leaks, specifically leaving the stove on when the flame is no longer burning.
Everyone’s done it - but if you quickly switch the burner off within a minute or two, it’s not particularly dangerous.
Some estimate that leaving a gas stove on without a flame for 10 to 15 minutes can increase gas concentration to explosive levels.
If you suspect your gas burner has been on that long, turn it off, open the windows and exit the building. If you’re experiencing the effects of gas inhalation, do not hesitate to call 999.
Conduct regular maintenance
Faulty appliances and wear and tear can cause minor gas leaks. Performing regular maintenance and health checks will reduce the odds of a gas leak developing via faulty appliances and damaged pipes.
Kitchen appliance cover protects your kitchen appliances in case something goes wrong, whereas boiler and heating cover protect against the cost of maintaining and repairing the boiler and related components.
What are the long-term effects of exposure to gas leaks?
No one should be exposed to gas leaks long-term.
However, on rare occasions, natural gas seepage from under the ground might cause prolonged gas exposure, which can cause various mental and physical issues.
Headaches, dizziness, respiratory issues
Prolonged exposure to natural gases like methane typically causes headaches and dizziness before anything else. Respiratory issues are also possible.
Long term exposure
Over time, even minor exposure to natural gas can cause serious respiratory, cardiovascular and neurological problems.
How can I stay safe from gas leaks?
Always be vigilant of leaving the gas on when your stove flame isn’t burning.
You might switch the burner on but not ignite the gas, or a breeze from a window or door could blow the flame out. This is becoming less likely as kitchens move towards electric hobs, but the point remains.
The main thing is to take no chances with gas leaks. Whereas a very subtle smell of gas may present no immediate danger, you should always get it checked out as soon as possible.
While this may or may not be evidence of a more serious gas leak, it’s still recommended that you call the emergency gas line if you’re at all worried or suspicious.
