Protect Yourself from Carbon Monoxide

Check out what you ned to know if you suspect fumes are escaping from your combustion appliance into your home, or your carbon monoxide alarm goes off.

For more information select a link below:

Quick Checklist

  1. After fitting your stove,  make sure your HETAS Installer has  fitted a carbon monoxide alarm in a location that is compliant with Building Regulations.
  2. If you suspect a CO escape turn your combustion appliance off, open doors and windows and leave property immediately. If you feel unwell, go to a doctor, call NHS Direct on 111 or in an emergency phone 999 for an ambulance.
  3. A CO alarm is not a substitute for:
    ∙ correct appliance operation *
    ∙ regular & effective chimney sweeping *
    ∙ correct appliance installation & maintenance * by a HETAS Registered Installer or Approved Servicing Technician

* Always follow the manufacturer’s instructions

Please make sure you read our two other important Consumer Advice pages before you use your new stove: Before Your Purchase & After Your Purchase

Early Symptoms of CO Poisoning

Early symptoms of carbon monoxide (CO) poisoning can be similar to many common ailments and easily be confused with  flu, viral infections, food poisoning, or simply tiredness. Symptoms include:

  • Headaches
  • Stomach pains
  • Nausea
  • Drowsiness
  • Erratic behaviour
  • Dizziness
  • Visual problems
  • Chest pains
  • Tiredness
  • Vomiting
  • Loss of consciousness

What to Do If You Suspect a CO Escape

If you suspect fumes are escaping from your combustion appliance into your home, or your carbon monoxide alarm goes off:

  • Where an appliance is automatically fed with fuel, turn it off
  • Open the doors and windows and ventilate thoroughly
  • Leave the property immediately and don’t return until your appliance or boiler has extinguished and any CO has dispersed
  • If you feel unwell, go to your doctor, call NHS Direct on 111 (0845 4647 in some areas) or if it is urgent phone 999 for an  ambulance. Tell them you feel your symptoms may be related to carbon monoxide poisoning

Before you re-use the appliance, have it inspected and the chimney checked by a HETAS Registered Installer, HETAS Approved Servicing and Maintenance Technician or Approved Chimney Sweep. Do not use the appliance until you are told it is safe to do so.

Your installer may need to fit a wall ventilator for extra combustion air. HETAS have approved a selection of vents, available to view at /find-appliance


Carbon monoxide (CO) is a toxic gas produced by poor combustion. Faulty combustion appliances including gas, oil & solid fuel can emit CO, usually accompanied by smoke in a solid fuel appliance. In some conditions this can be tasteless & odourless.

Solid fuels including wood are safe to burn in appliances that are installed and maintained properly. Where incidents of CO poisoning occur from solid fuel appliances, the most common fault by far is failure to maintain or service the appliance and failure to get the chimney swept properly.

We strongly advise that all installations, servicing and sweeping are carried out by HETAS Approved businesses


Building Regulations in England & Wales make it compulsory to fit a CO alarm when a new or replacement solid fuel appliance is fitted in a dwelling. HETAS recommend the CO alarm is installed by a HETAS Registered Installer to ensure it complies with Building Regulations (standard BS EN 50291).

For a list of Carbon Monoxide alarms recommended by HETAS

Carbon Monoxide Alarm Placement


  • in an enclosed space or where they can be obstructed
  • above a sink or in humid areas
  • next to a door, window, extractor fan or air vent, or near a cooking appliance
  • where temperatures drop below -10oC or above 40oC unless your model is designed to do so


Carbon Monoxide Alarm Placement

Ceiling mounted alarms - should be placed at least 300mm from any wall and between 1 metre and 3 metres horizontally from the appliance.

Wall mounted alarms - should be at least 150mm from the ceiling. If there is need to install on a wall with windows or doors, locate the alarm as high above these as possible, but still at least 150mm from the ceiling. Place between 1 metre and 3 metres horizontally from the appliance. If in a room with a sloping ceiling, locate alarm towards the highest side of the room.

CO Alarms must be in a permanent, fixed position and located in the same room as the appliance in line with approved document J, as pictured above.


  • Use appliances that fully comply with current British Standards
  • Get appliances installed by a registered competent installer to ensure work complies with current Building Regulations.
  • Regularly maintain your appliance using a HETAS Registered Installer or Approved Servicing Technician. Faulty appliances can lead to poor combustion which produces CO.
  • De-ash your appliance regularly as per manufacturers instructions
  • If the appliance burns wood, ensure it is dry & seasoned. Wet wood (unseasoned) produces less heat and more products of combustion containing CO. Ready to Burn or Woodsure certified wood fuel, guarantees low moisture content.
  • Make sure the appliance receives enough fresh air. Some appliances require a permanently open vent to external air located in the same room. This must remain unblocked. The appliance set-up must give enough combustion air to burn cleanly. An incorrect fuel-air mix can increase CO output.
  • Burn correct fuel for the appliance.
  • Make sure your chimney is swept at frequent intervals by a HETAS Approved Chimney Sweep. A blocked or restricted chimney will reduce flue performance, increasing the chances of the appliance spilling CO and other fumes.
  • Never operate a stove with its doors left open: CO can easily spill into the room.  When embers are “slumbering” without flames, they can produce high levels of CO
  • Responsible landlords should provide proof an appliance has been serviced and chimney recently swept before a tenancy starts. Ongoing maintenance of appliance & chimney is subject to contractual conditions detailing responsibilities
  • Carry out the user maintenance schedule as per the appliance ‘installation and use’ instructions.
Information extracted from: LEAFLET NO.3 - Protect Yourself from CO2 HETAS Consumer Advice

Alston - Ambleside - Appleby - Barrow in Furness - Brampton - Carlisle - Carnforth - Cockermouth - Dumfries - Keswick - Lancaster - Maryport - Morecambe - Penrith - Sedbergh - Silloth - Ulverston - Whitehaven - Windermere - Workington