Date Published: 09/01/2009 [Source]
Granite versus Radon
Solid Surface, The Journal of the Solid Surface Industry (Volume 1 Number 1) that was published several weeks ago, included an article entitled "Granite & Radon". The introduction to the article stated "Scientific research poses disturbing questions about the safety of granite countertops" and copies of this article have circulated around the stone industry raising questions about radon gas emissions from granite countertops.
Donald Langmuir, PhD, Professor Emeritus of Chemistry and Geochemistry at the Colorado School of Mines and President of Hydrochemical Systems Corp., both in Golden, Colorado, has prepared a response on behalf of the Marble Institute of America that evaluates and refutes these allegations. In addition to working with Dr. Langmuir and other scientists, the MIA staff also talked with the major U.S. granite quarriers and producers about the issue of radon emissions from granite. These companies have certainly not ignored the issue and several have had radon testing performed on their granites. The research done for these companies have shown that actual levels of radon gas emissions from granites are so low as to be insignificant and generally represent no threat to the health and well-being of people who live or work in buildings with granite countertops, floor or wall tiles, furniture or any other furnishings made from granite.
What is Radon?
Radon is a naturally occurring gas generated by the decay of trace amounts of uranium found in the earth's crust throughout the world. It is an unstable gas that quickly breaks down and dissipates in the air. Radon is measured in units called picocuries per liter (pCi/L). A picocurie is one trillionth (10 -12) of a curie, which is the amount of radioactivity emitted by a gram of radium. The U.S. Environmental Protection Agency (EPA) has established 4 pCi/L as the standard for indoor air; 20 pCi/L represents the maximum amount of exposure to radium that is now allowed by U.S. regulations.