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[L. radius, ray]
SYMB: Rn A chemical element, one of the noble gases, resulting from the disintegration of isotopes of radium, atomic weight (mass) 222, atomic number 86. Because radium is present in the earth's crust, radon and its disintegration products accumulate in caves, mines, houses (particularly those that are energy efficient), and any space where no free exchange exists between the air contained in it and the air outside it. Exposure to radon above acceptable limits is believed to be a risk factor for lung cancer.
SEE: noble gas
CAS # 10043-92-2

If the level of radon in a house is measured and exceeds acceptable limits, steps should be taken to reduce it. In some areas, this is a legal requirement for sale of a property. Methods for removing or decreasing radon exposure in buildings include the installation of fans for ventilation.

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