Carbon monoxide — the invisible danger in heating systems
Why carbon monoxide is so dangerous, and how you advise the customer to protect themselves
Carbon monoxide is one of the dangers a chimney sweep must be able to talk about with confidence — precisely because it cannot be seen or smelled. Carbon monoxide is an odourless, dangerous gas that can be emitted during incomplete combustion, and understanding how it arises is central to your advisory work.
§Why carbon monoxide is so dangerous
Because carbon monoxide can neither be seen nor smelled, it can accumulate in a room without any visible warning. It typically occurs with incomplete combustion — for example with poor draft, a clogged chimney, or a heating system that does not function as it should.
- 01Headache and dizziness
- 02Nausea and fatigue
- 03Confusion and difficulty concentrating
- 04In the worst case, unconsciousness and death at high concentrations
§The Safety Authority's recommendation
The Safety Authority recommends the use of carbon monoxide alarm in rooms where combustion-based heat sources without chimneys are used including gas ovens. A carbon monoxide alarm is an important extra safety layer but it can never replace proper installation maintenance and sufficient ventilation.
§The chimney sweep's role in preventing carbon monoxide poisoning
When you check draft and combustion you help prevent exactly that type of accident. Poor combustion and bad flue are a direct risk factor for carbon monoxide building up indoors — particularly in newer tight well-insulated homes where natural ventilation is less than in older houses.
§Advice to the customer
Tell the customer that they must never block air supply to a heating system that ventilation must be in order and that they should consider a carbon monoxide alarm — especially with combustion-based heat sources without chimneys. And emphasise that they should contact a professional if they experience signs that a system is not functioning correctly.