A properly conducted test will let you know the estimated average radon level in the home. Testing for radon comes in two forms: active and passive. Active devices usually require much longer periods of time then passive devices to collect the samples needed to provide a result. Passive devices are much quicker tests, 2-6 days, and therefore more suitable for real estate transactions. The most common passive device is metal cannister that contains activated charcoal. The canister is left open in the lowest level of the home which could be occupied. This excludes crawl spaces under the house, but includes finished or unfinished basements. The canister is retrieved after several days of exposure and sent to a professional lab for analysis. Concentrations of radon are described in terms of picocuries per liter of air (pCi/L). If concentrations of radon above 4 pCi/L are found in your home, the EPA recommends mitigation. For more information, visit the EPA web site on radon at http://www.epa.gov/radon.
If you're buying or selling a home, radon can be a significant issue. Exposer to radon over a period of years can have a significant and detrimental effect. In fact, it is the second leading cause of lung cancer in the United States according to the EPA. How widespread is the problem? Radon has been found in homes in all 50 states. Certain areas are more susceptible than others but no location is immune. Concentrations of radon in the soil can be either natural or manmade. Homes built near historic mining operations may be at higher risk. The only way to tell for sure is to have the home tested.
Radon is a radioactive gas that is created when uranium in the soil decays. The gas can seep through any access point into a home. Common entry points are cracks in the foundation or basement floor, poorly sealed pipes, drainage systems or any other access way to the soil.