Pollutants from these sources include formaldehyde, oxides of nitrogen, carbon monoxide, carbon dioxide and other chemicals, as well as fine particles of soot. Amounts produced will depend on the size of the space heater, how long it is in operation, whether the heater has been properly cleaned and adjusted, and ventilation of the room, among other factors. Likewise, use of a gas range will also produce these pollutants. Problems with the furnace or chimney can cause dangerous fumes to enter the house. Since the most deadly of these, carbon monoxide, has no odor, carbon monoxide alarms are very important for warning of this deadly gas.
Most combustion products are irritants to the eyes, nose, throat and lungs.
Effects include coughing, burning sensation in eyes, nose and throat, headaches and dizziness and sleepiness. Larger doses or prolonged exposure may have more serious effects. Some of these pollutants can increase the risk of cancer. Children with asthma may be more sensitive to the irritation caused by these pollutants. While large doses of carbon monoxide can kill, small amounts can cause nausea, muscle aches, tiredness and other symptoms resembling the flu.