Carbon Monoxide is a poisonous gas, that is odourless and cannot be detected by human senses making it a potentially lethal substance when concentrated in the home. There are many causes of carbon monoxide, but in the home, poorly installed, maintained central heating systems can be the cause of accidental exposure. Poor ventilation in the home, or blocked flues and chimneys can also cause a build-up of carbon monoxide. Proper maintenance of heating system can prevent issues with carbon monoxide, and it is also a good idea to install carbon monoxide detectors and alarms to alert you to any build up of carbon monoxide in the home.