If testing reveals that the house has low radon levels, the small cost of the removal tube can be considered fairly cheap insurance. The U.S. Environmental Protection Agency has a number of construction-oriented booklets dealing with radon control. While cancer is a disease that is certainly frightening, there are many other negative health effects associated with housing. For example, there are several hundred deaths each year attributable to carbon monoxide poisoning when furnaces malfunction. There are many more people who suffer from low level, non-lethal exposures.
Symptoms can range from headache and dizziness to cardiovascular and neurobehavioral effects.
There are probably many more people suffering who don't go to the hospital with their symptoms. Backdrafting and spillage are responsible for a variety of combustion gases entering a house, including carbon monoxide. Backdrafting refers to combustion by-products actually traveling down a flue or chimney, while spillage occurs when they don't go up fast enough, and some spill back into the furnace room. Backdrafting and spillage can occur when a house gets depressurized. Whenever you exhaust air from a building, you run the risk of depressurizing it.