Pico Curie per Liter, is broken down into two parts, the first is pico. Pico is simply a mathematical term for one trillionth. The second, Curie, is derived from Madame Curie who discovered that a gram of Radium produces 37 Billion decays per second. So 1 pCi/L (a trillionth of a Curie) equals 2.22 decays per minute per liter of air.
There is no known safe level of radon exposure. The EPA recommends that Americans consider fixing their home for radon levels between 2 pCi/L and 4 pCi/L. While the World Health Organization maintains an action level of 2.7 pCi/L.
Typically you should have 2 radon tests done before considering a radon mitigation system. Radon levels tend to fluctuate throughout the year. You can purchase short-term radon test kits from you’re local home improvement store or hire a professional to conduct a test.
Most types of granite used in counter-tops and other aspects of home construction are typically not major contributors of radon in the home.
Yes. Radon is a class A carcinogen. “Two studies, a North American study and a European study, both combined data from several previous residential studies. These two studies go a step beyond earlier findings. They confirm the radon health risks predicted by occupational studies of underground miners who breathed radon for a period of years. Early in the debate about radon-related risks, some researchers questioned whether occupational studies could be used to calculate risks from exposure to radon in the home environment.” (US EPA) These findings effectively end any doubts about the risk of radon exposure.
Soil vapor infiltration is one of the main causes of high humidity levels in a basement. A sub-slab depressurization system stops radon and vapor laden air from entering the basement while inducing sub-slab air movement that can reduce the moisture content of the floors and walls. Customers typically report a reduction in relative humidity and musty odors associated with mold. Every home is different and the effects of sub-slab depressurization on humidity levels vary from home to home. For more info you can access an EPA funded study here.
It should also be noted that a sub-slab depressurization system not only reduces radon gas entry into the home but also reduces any other chemicals or gases that are being drawn into the home, such as chemicals used by lawn fertilization companies.