Carbon Monoxide

Carbon Monoxide & Alarms

What is carbon monoxide – why is it a problem?


Carbon monoxide (CO) is a colourless, odourless, tasteless, poisonous gas produced by incomplete burning of carbon-based fuels, including gas, oil, wood and coal. Carbon-based fuels are usually safe to use, however, when the fuel does not burn properly, excess CO is produced, which is poisonous. When CO enters the body, it prevents the blood from bringing oxygen to cells, tissues, the brain and organs.


You cannot see it, taste it or smell it but CO can kill quickly with little warning. Around 50 people die every year from CO poisoning caused by gas, oil and solid fuel appliances and flues that have not been properly installed, maintained or that are poorly ventilated. Lower CO levels that do not kill immediately can cause serious harm to health if breathed in over a long period. In extreme cases paralysis and brain damage can be caused as a result of prolonged exposure to CO. Increasing public understanding of the risks of CO poisoning and taking sensible precautions could dramatically reduce this risk.


What preventative measures can I take?


  • Ensure that any work carried out in relation to gas appliances in domestic or commercial premises is to be undertaken by a Gas Safe Registered engineer, competent in that area of work.
  • HSE strongly advises that gas appliances and/or flues are installed and serviced regularly for safety by a Gas Safe Registered engineer. If you live in tenanted accommodation, your landlord has a legal duty to carry out an annual gas safety check and maintain gas appliances. They must provide you with a copy of the completed gas safety check certificate.
  • If you have a wood or coal burning stove fitted, make sure it is fitted by a HETAS approved installer. Make sure your chimneys are swept twice a year.
  • Always make sure there is enough fresh air in the room containing your gas, oil or solid fuel appliance. If you have a chimney or a flue, ensure it is not blocked up and also ensure that vents are not covered.
  • Do not use appliances like paraffin heaters and cabinet heaters in your house.
  • Never take a BBQ into a building or tent when it is still warm. When the embers have nearly died down, the BBQ will produce very large amounts of carbon monoxide!


Does the HSE recommend the use of carbon monoxide alarms?


The HSE strongly recommends the use of audible carbon monoxide (CO) alarms as an important precaution but they must not be regarded as a substitute for proper installation and maintenance of gas appliances by a Gas Safe Registered engineer. Before purchasing a CO alarm, always ensure it complies with British Standard EN 50291 and carries a British or European approval mark, such as a Kitemark. CO alarms should be installed, checked and serviced in line with the manufacturer’s instructions.


Please note: You can be particularly at risk from CO poisoning when you are asleep, because you may not be aware of early CO symptoms until it is too late. Having an audible CO alarm could wake you and save your life.


What are the symptoms of carbon monoxide poisoning?


Early symptoms of carbon monoxide (CO) poisoning can mimic many common ailments and may easily be confused with food poisoning, viral infections, flu or simple tiredness. Symptoms to look out for include:


  • Headaches
  • Breathlessness
  • Nausea
  • Dizziness
  • Collapse
  • Loss of consciousness
  • Tiredness
  • Drowsiness
  • Vomiting
  • Pains in the chest
  • Stomach pains
  • Erratic behaviour
  • Visual problems