What is Radon?
(January 13, 2005) The Surgeon General of the United States has issued a Health Advisory warning Americans about the health risk from exposure to radon in indoor air. The Nation’s Chief Physician urged Americans to test their homes to find out how much radon they might be breathing. Dr. Carmona also stressed the need to remedy the problem as soon as possible when the radon level is 4 pCi/L or more.Radon is a gaseous radioactive element having the symbol Rn, the atomic number 86, an atomic weight of 222, a melting point of -71ºC, a boiling point of -62ºC, and (depending on the source, there are between 20 and 25 isotopes of radon – 20 cited in the chemical summary, 25 listed in the table of isotopes); it is an extremely toxic, colorless gas; it can be condensed to a transparent liquid and to an opaque, glowing solid; it is derived from the radioactive decay of radium and is used in cancer treatment, as a tracer in leak detection, and in radiography.
Radon is a naturally occurring radioactive gas, you can’t see it, taste it, or smell it. Radon is formed from the natural decay of uranium in soil, rock and water. It can be found in almost all soil types and is found all over the world. 55% of the total radiation we are exposed to comes from radon. Even outdoor air we breath will have some levels of radon gas.
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Radon is an odorless, tasteless gas. It occurs from the natural radioactive decay of uranium in the soil. The radioactive decay products of radon are charged ions. They have a static charge that enables easy attachment to dust and smoke particles in the air. Radon is measured in units called picoCuries per liter (pCi/L). A picoCurie is a measure of actual radioactivity. Annual levels above 4 pCi/L are considered excessive, and some remedial action should be taken. Radon comes from various sources. It can come from rock; granite, shale, phosphate, and pitchblende are four likely rock sources, but others also have some percentage of uranium naturally occurring in them. Radon moves easily through porous, permeable materials. It can come from well water, natural gas, and in rare cases, some building materials such as concrete which can contain and emit radon. Elevated indoor concentrations of radon can be found in every state. Uranium is present in most of the soil in the world. However, s
