What causescarbon monoxide to leak?

Carbon monoxideis produced whenfuels such asgas, oil, coal and wooddon't burn fully.

Burning charcoal, running cars and the smoke fromcigarettes also produce carbon monoxide gas.

Gas, oil, coal and wood aresources of fuel used in many household appliances, including:

  • boilers
  • gas fires
  • central heating systems
  • water heaters
  • cookers
  • open fires

Incorrectly installed, poorly maintained or poorly ventilatedhousehold appliancessuch as cookers, heaters and central heating boilersare the most common causes of accidental exposure to carbon monoxide.

The risk of exposure tocarbon monoxidefrom portable devices may also be higher in caravans, boats and mobile homes.

Other possiblecauses of carbon monoxidepoisoning include:

  • blocked flues and chimneys this can stop carbon monoxide escaping,allowing it to reach dangerous levels
  • burning fuel in an enclosed or unventilated space for example, running a car engine, petrol-powered generator or barbecue inside a garage, or a faulty boiler in an enclosedkitchen
  • faulty or blocked car exhausts a leakorblockage in the exhaust pipe, such as after heavy snowfall, could lead to a build-up of carbon monoxide
  • paint fumes some cleaning fluids and paint removers contain methylene chloride (dichloromethane), whichcan cause carbon monoxidepoisoning ifbreathed in
  • smoking shisha pipes indoors shisha pipes burn charcoal and tobacco, which can lead to a build-up of carbon monoxide in enclosed or unventilated rooms
Content supplied by the NHS Website

Medically Reviewed by a doctor on 21 Dec 2018