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Carbon monoxide

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Technical guidance on Schedule 1 of the Building Regulations about heat producing appliances.
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Carbon monoxide is a gas, produced when carbon based fuel is burnt without enough oxygen.  

You cannot see, smell or taste it but it can injure and kill quickly. 

It is responsible for a considerable number of deaths each year, and for many more cases of poisoning. Many people are likely to be affected by carbon monoxide without realising it. Thousands of cases of carbon monoxide poisoning go unreported.

Where does it come from? 

Any household or garden appliance that uses carbon based fuel can produce carbon monoxide if it is burnt without an adequate supply of oxygen. Potential sources include:

  • gas (mains or bottled): stoves, fires, water heaters and boilers
  • solid fuel: coal, charcoal and wood – stoves and fires
  • oil powered appliances such as boilers and heaters
  • barbeques, portable stoves and heaters
  • generators (diesel, petrol or gas).

How can I tell if I’m at risk?

Carbon monoxide is easily absorbed into the bloodstream by breathing it in. Anyone can be affected by carbon monoxide poisoning. The symptoms can look like everyday illnesses: headaches, dizziness, feeling sick and tiredness.

Do not ignore these symptoms if:
  • other people in the same building have similar problems 
  • you’ve recently moved into the building 
  • you’ve had a new appliance fitted e.g. boiler, log burner or a cooker 
  • you’ve had work carried out that might affect ventilation e.g. double glazing 
  • you feel better when out of the building 
  • you’ve recently switched the heating on.
If you think you have been affected by carbon monoxide do not delay, take the following action:
  • stop using any fuel burning appliances or devices until they have been checked by a registered engineer 
  • go outside and get fresh air 
  • seek medical advice – NHS Direct Wales can help  0845 46 47
  • see your GP and tell the doctor if you think something in your house has caused your symptoms
  • call the gas emergency line on 0800 111 999. 
In a medical emergency phone 999 

Technical advice for health professionals on diagnosing and reporting carbon monoxide poisoning is given in the document below. Further information is also available from Public Health Wales (external link)

See also:   

Public health England - Carbon monoxide awareness (external link)

The Gas Safety Trust (external link)

NHS Direct Wales - Carbon Monoxide Poisoning (external link)