WHERE DOES RADON COME FROM?
Radon comes from the natural radioactive decay of radium and uranium found in the soil beneath the house. The amount of radon in the soil depends on soil chemistry, which varies from one house to the next. Radon levels in the soil range from a few hundred to several thousands of pCi/L. The amount of radon that escapes from the soil to enter the house depends on the weather, soil porosity, soil moisture, and the suction within the house.
Radon is constantly being generated by the radium in rocks, soil, water and materials derived from rocks and soils. The radon generated in rocks or water usually stays trapped in that material unless the rocks are fractured or the water is mixed with the air (shower, laundry room). Radon-222 is the decay product of radium-226. Radon-222 and its parent, radium-226, are part of the long decay chain for uranium-238. Since uranium is essentially ubiquitous (it is everywhere) in the earth’s crust, radium-226 and radon-222 are present in almost all rock and all soil types. The amount of radon in the soil depends on the soil chemistry, which varies from one house to the next. Radon levels in the soil range from a few hundred to several thousands of pCi/L (picoCuries per Liter). The amount of radon that escapes from the soil to enter the house depends on the suction created within the house, soil porosity, soil moisture, and the weather.
Radon is constantly being generated by the radium in rocks, soil, water and materials derived from rocks and soils. Radium is present at about 0.5 to 5 parts per million (PPM) in common rocks and soils. The radon generated in rocks or water usually stays trapped in that material unless the rocks are highly fractured or the water is mixed with the air. Radon generated in soil has about a 40% chance of escaping into the soil gas.
