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What is carbon monoxide (CO)?

Knowing the signs and symptoms of carbon monoxide poisoning could save your life!

Carbon monoxide is a highly poisonous and sometimes fatal gas. It is difficult to detect as you can't see it, taste it or smell it. 
Carbon monoxide comes from fuel burning appliances which are not fitted correctly, are badly repaired or maintained such as fires, boilers, chimneys, gas cookers and water heaters. Gas, oil and solid fuels such as coal, coke and wood can all produce carbon monoxide.

Are you suffering from CO poisoning?

The signs carbon monoxide poisoning are similar to flu-like symptoms, so it is important to be aware of the signs and other things to look for:

  • Headaches
  • Dizziness
  • Nausea
  • Breathlessness
  • Collapsing
  • Loss of consciousness

Look for:

  • Symptoms improving when you leave home, but reoccur once back inside the property
  • Symptoms are worsening in the winter when fuel burning heaters are used more frequently
  • Symptoms appearing or worsening when gas and other fuel burning appliances are in use
  • More than one person in your household (including your pets) are
    experiencing similar symptoms

What to do next:

If you experience any of these symptoms, seek immediate medical advice from your GP: 

    Call NHS Direct on 0845 46 47 

    Call NHS 24 in Scotland on 08454 242424


If it's urgent, call 999 for an ambulance.

For more information on the signs of carbon monoxide poisoning and how it is treated, please visit this useful page on Netdoctor.

Also look out for...

It is also important to check appliances for signs of carbon monoxide poisoning - these may include:

  • black soot marks on gas fire burners or on walls near cookers, boilers, gas fires
  • a yellow gas flame, rather than the blue colour as it should be.