The smell of gas within your home can be alarming and should be treated seriously. Knowing how to react to a gas emergency could save your property and, more importantly, the lives of those within it.

We’ve got some tips to help you know what to do if you smell gas in your home.

Prefer to watch?

How to recognise the smell of gas

Natural gas has no smell, so a leak would normally be impossible to detect. So to combat this, Mercaptan, a harmless chemical that smells like sulphur or rotten eggs, is added during processing to help you identify a gas leak.

Even if you don’t know what a gas leak smells like, the smell of rotten eggs should be enough to make you realise there’s a problem in somewhere in your home.

As a sidenote – carbon monoxide, another hazardous gas, also has no odour. That’s why every home should a carbon monoxide alarm. We’ve got a short video on carbon monoxide safety that explains what you need to do if your alarm goes off.

What to do if you smell gas

In the following section, we’ll outline the steps you need to take if you smell gas. From ventilating your property to evacuating and calling the emergency helpline – every second counts to ensure the safety of your home and those within it.

1. Ventilate the property and shut off the gas

If you smell gas:

  • Open any doors and windows wide to allow fresh air in for ventilation  
  • Find the gas shut-off valve (it’s usually near your gas meter)
  • Turn the valve lever 90 degrees so that it doesn’t line up with the gas supply pipe

Your gas supply should now be shut off.

Make sure you know where your gas shut-off valve is and what it looks like before you need to use it. It’s normally a metal lever and can have a red or yellow handle for extra visibility.

2. Evacuate the property

Once you’ve shut the gas off you should leave your property immediately. Avoid doing anything which could ignite the gas. This means definitely no smoking or turning on any electrical or light switches. Move calmly and quickly outside and don’t go back inside until the emergency services have given you the all-clear.

3. Call the National Gas Emergency Helpline

Once outside, you should contact the National Gas Emergency Service. If you live in the UK, the telephone number is free but the number differs based on where you are and the type of gas involved:

Location Natural gas leaks  Liquified petroleum gas leaks Towns or mains gas leaks*
England, Wales and Scotland 0800 111 999 Contact number on meter N/A
Northern Ireland 0800 002 001 Contact number on meter N/A
Isle of Man 0808 1624 444 0808 1624 444 0808 1624 444


N/A 01481 749000 01481 749000
Jersey N/A 01534 755555 01534 755555

*Guernsey and Jersey use a manufactured gas mixture (commonly known as ‘mains gas’) supplied from an underground mains system. The Isle of Man has a similar system (known as ‘towns gas’) but is being converted to natural gas.

What happens after you call Gas Emergency Service

When you call the National Gas Emergency Service, they’ll send a Gas Safe engineer to your address to assess the situation. The engineer will check for any gas leaks and if they find one, they’ll repair it and make your property safe again. However, it might be a little while before your gas supply can be safely turned back on – depending on the extent of the repairs needed.

Will the engineer fix any faulty appliances?

The top priority of the engineer who visits is to check for gas leaks and make your property safe again. If they find that your appliance is faulty and the cause of the leak, they’ll explain this to you but it’s unlikely they’ll carry out any major appliance repairs. Thankfully it’s easy to arrange for an expert to repair your appliance.

How to protect against gas leaks

To help reduce any risk of a gas leak, there are a few safety measures you can take:

Get your boiler serviced regularly

Getting your boiler serviced regularly is crucial for your safety as it detects any potential gas leaks. But it’s also important for ensuring the efficiency of your boiler and to keep it running at its best. You should aim to get your boiler serviced once a year to detect any issues early on.

Inspect and maintain your gas appliances

Inspecting and maintaining your gas appliances means you can be confident they’re working reliably and efficiently. Carry out regular checks for any signs of wear and tear. Just as regular maintenance means you can be sure your boiler is working safely, by addressing any faults with your appliances early on, you can prevent potential gas leaks.

Familiarise yourself with your gas meter

Don’t be a stranger to your gas meter. If there’s a gas leak, you’ll save valuable time knowing how to shut off the gas. As mentioned earlier on, by knowing what your gas shut-off valve looks like and where it is beforehand, you can act swiftly if you’re faced with a potential emergency.

What to do if you need to repair a gas appliance

Regular maintenance of your gas appliances and acting promptly to fix any faults with them is vital. If you do discover that your appliance is faulty, it’s quick and easy to arrange for a gas safe engineer to come out and repair it.

About the author

Ian Palmer-Smith

With 39 years working in operations, appliance maintenance and repairs. Ian is our go to expert for all things appliances. He is known for having the answer to any boiler query or washing machine debate on the tip of his tongue. Ian regularly contributes to the blog to share his wisdom further afield and help people out when our appliances aren’t working as we expect.

Last year, Ian was recognised as a finalist in the Institution of Gas Engineers and Managers’ Gas Leadership Award, a testament to his authority in the industry.

Ian is passionate about promoting awareness for carbon monoxide safety and has even represented Domestic and General at the House of Commons to discuss the importance of carbon monoxide safety around the home.

When not at work, Ian is occupied by taxing his sons to various sporting events, watching  football, rugby and more sports,.

To benefit from Ian’s wealth of knowledge on all things gas safety and appliance care, check out some of his blogs below.

Our blog is loaded with more related articles