What is carbon monoxide?

Carbon monoxide, known as CO for short, is a toxic gas, which cannot be seen, tasted or smelt ©-Arestov-Andrew-Fotolia

Carbon monoxide, known as CO for short, is a toxic gas, which cannot be seen, tasted or smelt. It results, among other things, from incomplete combustion processes of fossil fuels such as oil, gas, coal, wood, charcoal and petroleum. However, the danger only starts when this combustion takes place in a confined space and not in the open air, as with a barbecue for example. Defective devices or systems can result in retention or backflow of exhaust gases. In this case, not all the chimney smoke is channelled away via the chimney or exhaust gases from the kitchen gas stove are not properly channelled away. This is the way excessive carbon monoxide forms in garages as well. 

Carbon monoxide may accumulate under certain circumstances for several days, resulting in insidious poisoning – until the concentration of carbon monoxide becomes excessive and fatal to people. 

Typical sources of danger include:

Blocked chimneys

If chimneys are blocked, exhaust gases can no longer be sufficiently removed from the residence or house - or at all. Blocked chimneys – due to birds’ nests or other garbage – are frequently a reason why people succumb to carbon monoxide poisoning while asleep.

Fireplace, gas stove, oil and gas heating, grills

Devices which run on fossil fuels are an additional source of danger. The scope of fossil fuels includes coal, crude oil and natural gas, which are used in many devices in homes and gardens, such as: 

  • Fireplaces and stoves
  • Gas stoves
  • Oil and gas heating systems featuring oil and gas boilers or solid fossil fuels such as wood, coal or pellets, flow heaters
  • Wood or electric grills


Have your chimneys, fireplaces and all other relevant devices such as heating systems checked by a specialist regularly. 



Based on the non-specific symptoms, it is generally difficult to detect whether carbon monoxide poisoning has taken place. 


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