A cancer-causing radioactive gas that comes from the soil and can seep into any type of building- house, office, school, hospital, etc.…It can get in through cracks in solid floors and walls, construction joints, gaps in suspended floors and around service pipes, cavities inside walls and even in the water supply.
It is found all over the United States, but areas are broken into three zones measured in picocuries per liter of air (pCi/L).
No level of radon is safe, but anything above 4 pCi/L needs to be mitigated. Franklin County, PA and the immediate surrounding counties are all in Zone 1 meaning those counties have the highest radon exposure risk.
However, if your next-door neighbor’s house tests at 27 pCi/L, your home could test at 36 pCi/L or it could test 2 pCi/L. Many factors play a part in radon levels. The building structure, the wind, how much uranium is in the soil, rocks or water etc…
Just because the surrounding area tests high doesn’t mean your house will test high.
But the only way to know is to test.