Carbon monoxide: the invisible killer


How do you protect you and your family from something you can't see, taste, or smell?

Carbon monoxide (CO) is deadly, poisonous gas that can kill in just a few hours. 

It's released through the improper burning of fossil fuels like coal, oil, wood, and gas in poorly ventilated areas – often the result of an incorrectly installed or maintained appliance.

Because it's very difficult to detect, you're most vulnerable when you're asleep. It's therefore vital you stay vigilant to the early warning signs so that you can catch carbon monoxide before it harms you.

Warning signs


Have you, or someone in your family, experienced any of the following – especially if they go away after you leave the home?

  • Flu-like symptoms
  • Nausea
  • Headaches
  • Drowsiness
  • Dizziness
  • Chest pain
  • Stomach pain 
  • Breathlessness

If the answer to the above is yes, then ask yourself:

  • How many in your home are affected?
  • Do the symptoms disappear or reduce away from home?
  • Do the symptoms appear or get worse in the presence of a fuel-burning appliance?
  • Are the symptoms worse in cold weather when the heating's on?

Your appliances

Have you, or any of your family, noticed any of these signs:

  • Yellow or orange flames
  • Soot around the appliance
  • Stains around the appliance
  • Regular extinguishing of pilot lights

If you think you've been exposed to carbon monoxide

If you think you've been exposed to carbon monoxide, or believe you've an appliance emitting it in your home, go to hospital immediately and tell them you've been poisoned by carbon monoxide. They'll measure your carboxyhaemoglobin level with a blood test. As you'll be considered an emergency case, ask a friend or family member to go with you.

Protect yourself and your family

There are a few things you can do to prevent carbon monoxide poisoning:

  1. Ensure all your gas-powered appliances have been installed and maintained by a Gas Safe Register™ engineer.
  2. Don't block ventilation.
  3. Service all your fuel-burning appliances regularly.
  4. Install a carbon monoxide detector with an audible alarm. A carbon monoxide detector will tell you if carbon monoxide is in your home. As you're vulnerable while sleeping, a carbon monoxide detector with an audible alarm is the safest option – make sure it complies with British Standard EN 50291 and carries a British or European approval mark, such as a Kitemark. Carbon monoxide detectors should be installed, checked and serviced in line with the manufacturer’s instructions.

For more information on carbon monoxide, visit:

Health and Safety Executive


Carbon Monoxide Safety

Carbon Monoxide Consumer Awareness Alliance (COCAA)

Are you eligible for a free gas safety check?

If you're on our Priority Services Register and live alone or with others who are of pensionable age, chronically sick or disabled, or you live with a child under the age of 5 then you could be eligible for a free gas safety check provided:

  1. You do not live in a property where the landlord is responsible for arranging a gas safety check.
  2. You receive a means tested benefit.
  3. You have not had a gas safety check carried out in the premises in the last 12 months.

Your check will be carried out by qualified person and will include checks of gas appliances and any other gas fittings. We’ll check the effectiveness of any flue, the air-supply, the operating pressure and that it is functioning safely. To arrange your gas safety check call us on 0808 164 1088.

Safe Use Of Gas Appliances

It's absolutely essential that gas appliances and fittings are properly installed and maintained – otherwise it could result in gas leaks or carbon monoxide poisoning.

Follow these guidelines at all times:

  1. Don't use any gas appliances that you think aren't working properly.
  2. Ensure ventilation bricks, grilles, or outside flues are never covered or blocked.
  3. Ensure your gas appliances are serviced at least once a year by a Gas Safe Register™ engineer.
  4. Install a carbon monoxide detector.
  5. Don't allow unqualified people to install or maintain your appliance.

If in doubt, or if you smell gas, call the National Gas Emergency Helpline on 0800 111 999.

Published on 9th June 2017 by:

image of Chris Roper

Chris Roper


Hey I'm Constantine, welcome to Octopus Energy!