Keeping your family safe is our number one priority at British Gas. Understanding the dangers around Carbon Monoxide can save lives.

What is Carbon Monoxide?

Carbon Monoxide is a highly poisonous gas that is very difficult to detect as you cannot see, smell or taste it. You may not be aware of its presence until it is too late as Carbon Monoxide has no taste, smell or colour.

  • High levels of Carbon Monoxide exposure can prove to be fatal, even low exposure can cause lasting damage.
  • Carbon Monoxide is known as the silent killer as around 30 people die each year from Carbon Monoxide poisoning, and many more are seriously injured. For more information, visit the CO Be Alarmed website.

Sources: Gas Safe and COCAA

Symptoms of Carbon Monoxide poisoning?

The symptoms of Carbon Monoxide poisoning can be similar to flu. If you are suffering from Carbon Monoxide poisoning you may suffer from: Headaches, Nausea, General lethargy, Dizziness, Flu-like symptoms that appear to get better when you are away from the area.

Asking yourself some basic questions may help you to assess the situation:

  • Is more than one person in the house affected?
  • Do the symptoms ease or disappear when you are away from the house, e.g. on holiday, but recur on returning home?
  • Are the symptoms related to the use of a fuel burning appliance?
  • Are the symptoms worse in winter, when the heating is in use?

Where does Carbon Monoxide come from?

All appliances that burn wood or fossil fuels can emit Carbon monoxide.

  • Carbon Monoxide is produced when these fuels are burned without sufficient air or ventilation. That's why it is often produced by appliances that have been incorrectly installed or maintained.
  • If you have an oil, gas or wood burning boiler, fire, water heater or cooker you should fit a Carbon Monoxide alarm.

Key simple checks

Carbon Monoxide is difficult to detect but there are some simple signs to look out for:

  • Staining, sooting or discoloration on or around your gas boiler, fire and water heater.
  • Keep air vents in doors, walls or windows clear and make sure your chimney or flue isn't blocked.
  • Check pilot lights and other gas flames that normally burn blue. If the flame changes to yellow or orange, CO might be present.
  • Have your appliances and flues checked each year.


If you believe you or any of your family are suffering from Carbon Monoxide poisoning please consult your doctor immediately.

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