Radon is a cancer-causing radioactive gas that occurs naturally in the soil. No level of radon gas is completely safe. The Minnesota Department of Health estimates that 1 in 3 Minnesota homes have harmful levels of radon gas in their homes. The air pressure inside our homes is usually lower than the pressure outside; this difference makes our basements act like a vacuum bringing radon in through cracks or other openings.
Why is it harmful? Radon is the second leading cause of lung cancer in the world and is thought to be responsible for 20,000 deaths a year. The Minnesota Department of Health recommends that every Minnesota home be tested for radon. Just because your neighbor’s home doesn’t have radon doesn’t mean yours won’t be affected.
The EPA website states:
The U.S. Congress has set a long-term goal that indoor radon levels be no more than outdoor levels; about 0.4 pCi/L of radon is normally found in the outside air. EPA recommends fixing your home if the results of one long-term test or the average of two short-term tests show radon levels of 4 pCi/L or higher. (The World Health Organization recommends 2.7pCi/L.)When we purchased our home nine years ago I did a radon test and found that the level was a bit elevated. Knowing we would be spending more time in the basement once it was remodeled I tested for radon a second time using the method described in the following Minnesota Department of Health video.
Those tests results indicated a 3.9 pci/L level not terribly high but it could be reduced.
I consulted with Walt of Advanced Radon Services. His company sealed the two sump pumps in our basement floor to stop air from seeping up through them. I am hoping that pouring the new concrete floor and repairing the walls will also help lower the level.
When our project is over I will retest. If the level hasn’t been reduced I will consider having an air exchange system installed. Due to the fact that the Midwest has a fairly high incidence of radon I feel that designers, contractors and builders have a responsibility to encourage homeowners to test for radon and to lower the levels in their homes if necessary.
If you have further questions about Radon, this Environmental Protection Agency site should help answer your questions.