Granite versus Radon

Granite versus Radon


This information was prepared for you to distribute to your customers and others who have questions or concerns about the radon and granite issue. It is copyrighted by the Marble Institute of America, but may be reproduced, with credit given to the Marble Institute of America.

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. The key advertisers in this journal were Corian and Formica.
The MIA has called upon several of the country's leading scientists in geology and geochemistry to assist in preparing a response to the allegations in this article that radon gas emissions from granite countertops may be hazardous. On reading the article, our consultants reacted with such comments as "ludicrous", "a fabulous collage of nonsense", "politically motivated", "unethical", and "bizarre".
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. His report appears in full in this Special Bulletin. Dr. Langmuir received his BA (with honors), and his MA and PhD degrees in geochemistry from Harvard University. He served as a geochemist with the Ground Water Branch of the U.S. Geological Survey's Water Resources Division and subsequently taught and conducted research for 11 years at Pennsylvania State University, with temporary appointments at Rutgers University, the Nevada Desert Research Institute, and the University of Sidney, Australia. Dr. Langmuir has been a full professor at the Colorado School of Mines since 1978.
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.
Marbles, limestones and stones other than granites are of such mineral composition that they generally do not contain measurable quantities of radon-producing material. In terms of building materials, radon emissions from concrete, cement and gypsum could be of greater concern.

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.