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Gas Leak Symptoms


Around 85% of UK households use natural gas to fire their boilers for hot water and central heating needs. Natural gas is also fuel for several consumer products such as stoves, clothes dryers and furnaces. As such, chances are pretty high that one or two appliances in your household run on natural gas.

Although natural gas is considered the world’s cleanest fossil fuel, it can still be dangerous if improperly handled. Given that it is a flammable material, a gas leak in your home can pose risks of explosions and fires. Additionally, inhaling the gas can cause natural gas poisoning and even suffocation by displacing air in confined spaces.

Given the risks associated with a gas leak, everyone must learn how to detect the presence of a gas leak in their homes.  It is also necessary to understand what to do right after being exposed to a gas leak. This way, you will be able to keep yourself and your loved ones safe in the event of a gas leak.

What is a gas leak?

A gas leak is when natural gas or other gaseous product leaks from the pipeline or another containment into an area where it shouldn’t be. In this case, your home and its surroundings

What causes a gas leak?

Gas leaks in households usually result from poorly fitted, ill-maintained or faulty appliances like cookers and boilers. Old and rusty gas pipes usually in older properties are also to blame for gas leaks in households.

For example, if the gas hose that leads to the boiler isn’t secured well, gas can easily leak out of it. It is, therefore, vital to ensure that an accredited Gas Safe engineer is the one installing your boiler and other gas-fueled appliances. You should also be wary of old or reconditioned gas appliances as they may be leaky.

What are the symptoms of a gas leak?

Learning how to identify a gas leak in your home is the very first step to protecting yourself and your family from the potential hazards of a gas leak. Otherwise, how can you defend against a foe you know not of its existence?

Luckily, there are various ways to detect the presence of a gas leak in your home. However, you should note that identifying and fixing a gas leak are two different things, one of which is better left to a certified Gas Safe engineer. On the other hand, you should evacuate when you notice one or a combination of the following symptoms of a gas leak.

Rotten egg smell

Since natural gas is odourless, it would be impossible to detect a gas leak if it was in this form. To prevent the leak from going undetected and potentially building up to dangerous levels, gas companies add harmless chemicals called odorant to give the gas a unique smell. The odorant commonly used is called mercaptan and smells like sulphur or rotten eggs.

Therefore, if you notice the smell of rotten eggs around your home, it is highly likely that there is a gas leak in your home. Generally, the stronger the smell, the higher the concentration of the leaked gas.

You might also be able to catch a slight whiff of this smell coming off your gas grill if it is more than 15 years old. Thankfully, the more energy-efficient grills made in the last 15 years don’t produce this smell when turned on.

Hissing or whistling sounds

The second indicator that your home has a gas leak is the gas pipes and appliances producing hissing or whistling sounds even when the equipment isn’t operational. The good about hissing or whistling pipes and gas appliances is that you can easily trace and fix them. So if you regularly inspect gas pipes and appliances looking for hissing or whistling sounds, you can isolate and fix the leaks before they develop further.

Sickness and fatigue

In some situations, you may be having a gas leak in your home without you noticing. Undetected gas leaks are most common where the gas leaks are small that you can’t easily smell the distinct odour of the gas or hear hissing noises from leaking pipes.

Well, your body will notice on its own. As earlier said, natural gas displaces the oxygen present in the room. As the oxygen in the room thins, you or your family member will begin to develop sudden physical symptoms such as headaches, dizziness and nausea.

Other symptoms of gas poisoning include nosebleeding, difficulty in breathing, and loss of appetite.

Blowing dust or bubbles in standing water

If on one of your rounds you observe a bubble in standing water or mud lying directly above your home’s gas supply pipe, then you are probably facing a gas leak. As the leaked gas disperses through the soil into the surrounding air, it will cause bubbles in the water or mud. If it is the dry season, the escaping gas will raise a continuous cloud of dust.

Unhealthy houseplants

If there is a small leak in your home and it goes undetected for long, the amount of oxygen in the room will start to drop. With dwindling oxygen levels, the indoor plants in your home will begin to wither and look sickly. Eventually, some of the plants in your kitchen, dining room, or bedroom will start dying. You can quickly notice these if you often care for your indoor plants.

Abnormally high gas usage

One red flag that your gas supply system is leaking is when you notice your gas usage is higher than usual.  If your natural gas usage suddenly surges – say, nearly doubles in one month, it might indicate the presence of a gas leak somewhere in or around your home.

Dead and dying plants outside the house

As earlier said, a gas leak in your home may occur either inside the house or on the outside. If the gas leak happens outside the house, for example, if the underground gas line passing through the yard is leaking, the escaped gas will seep into the soil. The presence of natural gas in the sub-soil will prevent the plant roots from absorbing oxygen, causing the plants will wilt and die.

Discoloured flames

When operating normally, your gas furnace should produce a hot blue flame when activated. On the other hand, when there is a leak in the gas supply hose, the furnace will burn with a tired-looking orange or yellow flame. However, a gas leak isn’t always the reason since the cooker may be having other underlying issues. To better ascertain that the orange flame is due to a gas leak, you should contact a professional gas tradesperson.

What to do if you have a natural gas leak in your home?

As always, your safety and that of your family come first. So the first thing you should do is instruct everyone in the building to evacuate immediately and regroup in a pre-determined location. Leaving the building immediately after a gas leak is detected will help limit your exposure to the gas. Additionally, it will put a safe distance between you and the property if the gas leak were to ignite.

While evacuating, ensure that all doors and windows to the property are left wide open to allow the natural gas to vent outdoors. Leaving the doors and windows open will prevent the leaked gas from accumulating to levels that can set off an explosion.

Once everyone is outside the building and is a safe distance away, call for help. You can either reach the 112, the local fire department, or the gas emergency number 0800 111 999.

What not to do in case of a gas leak

Here are some things you should never do if you suspect a gas leak situation in your home.

  • Do not search for the source of the leak but use this time to evacuate.
  • Do not attempt to repair the leak on your own.
  • Do not use electronics inside the house as they can generate sparks that may ignite the leaked gas.
  • Do not close the windows and doors of the building as you evacuate.
  • Do not strike matches or lighters within the vicinity of the building.
  • Do not forget to report the incident.
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