Carbon Monoxide Poisoning – Signs and Symptoms

Carbon Monoxide has no smell, no taste and can’t be seen. It is responsible for, on average, 50 deaths and 4000 hospital visits a year in the UK. In this post, we take a closer look at Carbon Monoxide poisoning, the symptoms to look out for and what actions you can take to prevent it.

Carbon Monoxide Poisoning

What is Carbon Monoxide?

Carbon Monoxide (CO) is a gas and a by-product of combustion that is produced when certain types of fuel do not burn fully. Around the home, gas is the most used potential source of Carbon Monoxide. However, coal, wood and oil can also create it.

What Causes Carbon Monoxide?

There are many items around the average home that have the potential to create carbon monoxide. The most common causes of exposure to carbon monoxide are poorly fitted or poorly maintained household appliances such as central heating systems, cookers and heaters that have been incorrectly installed or badly ventilated.

Other potential sources of Carbon Monoxide gas include;

  • The fumes from some types of paint removers and cleaning fluids can contain carbon monoxide.
  • Blocked chimneys and flues can prevent carbon monoxide from escaping, creating a build-up that can become dangerous.
  • Cars produce Carbon Monoxide when running. If you allow a car to run in an enclosed, poorly ventilated space, it will result in a CO gas build up.
  • The same is true if you run a petrol powered generator or barbecue in an enclosed space.

What Are The Symptoms of Carbon Monoxide Poisoning?

It’s not always obvious that you have Carbon Monoxide poisoning as the symptoms can be mistaken for other ailments such as food poisoning or flu.

Low-level exposure to Carbon monoxide typically results in a tension-type headache. You may also experience sickness, shortness of breath, dizziness, tiredness and feeling confused.

Symptoms will lessen when you’re away from the CO source. For example, if you’re feeling poorly at home but better when you go to work, it could be a sign of a Carbon Monoxide leak within your property.

Higher level carbon monoxide exposure typically causes more severe symptoms; these may include feeling drunk/intoxicated, breathlessness and a racing heartbeat, chest pains, muscle spasms and unconsciousness.

What Should You Do If You Think You Have Carbon Monoxide Poisoning?

If you believe that you are suffering from Carbon Monoxide poisoning, the first thing you should do is find fresh air straight away. Next, open all doors and windows and turn off any gas appliances and leave the house.

You should then seek medical attention immediately. CO poisoning is relatively easy to detect with a blood or breath test.
If you think there is serious Carbon Monoxide leak, then you are advised to call the Gas Emergency Helpline on 0800 111 999.

Finally, contact a Gas Safe registered gas engineer to inspect your appliances and flues.

Possible Signs of a Carbon Monoxide Leak

There are some signs to look for that can point to a Carbon Monoxide leak around your home.

• Pilot lights blow out regularly.
• Increased condensation build-up on windows.
• Flames on your gas hob are a yellow or orange colour rather than bright blue.
• Dark patches or staining on appliances.

Carbon Monoxide Detectors

The Health and Safety Executive advise that audible Carbon Monoxide Detectors/Alarms be fitted in every room which has a gas appliance. Devices with alarms are favoured as they will wake you up if CO gas is detected while you are asleep. When purchasing a detector check that it complies with British Standard EN 50291. It should also carry a British or European approval mark, such as a Kitemark.


It’s best to start on the right foot and check that any gas engineers that are doing work for you are Gas Safe Registered. If you are worried or unsure about any appliances within your home, then have them checked by a Gas Safe registered gas engineer.

As a second line of defence, a Carbon Monoxide alarm should be fitted near your gas appliances. Should a leak occur, you will be warned in plenty of time and can take the necessary actions.

If you have any concerns or would like to book an appointment to have appliances serviced or checked, please get in touch with our team.