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R a d o n     R e p o r t s   :    R a n t     o r    R e a l ?

editorial by Brian Laws



Over the years, we have seen the occasional rise of negative media attention regarding the possibility of hazardous amounts of radon being emitted from natural stone countertops. Some very alarming figures have been in circulation about this subject and have seen varying degrees of public attention. Most often printed in magazines and internet sites that either have misinformed or skewed information (sometimes intentionally done to generate an alarmist response and thereby increase the sales of sponsoring companies).

Because Alexander's Stone Art is not only a natural stone fabricator who may see decreased sales due to a possible consumer misconception, but also because we are very concerned in the health of our customers and our employees, we have spent several hours researching these sources of information on radon as well as less public and more scientific oriented materials on radon and the possible dangers that it may present.

Here is what we have found.

So What Exactly is Radon?

Radon (Rn-222) is a naturally occurring radioactive 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” or pCi/L. A picocurie is one trillionth or 10-12 of a curie (a curie 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.

Radon has been deemed as the second leading cause for lung cancer in the U.S. and is commonly found throughout the U.S. in varying levels. Radon, being heavier than air usually pools in low areas with little ventilation such as crawl spaces and basements.

In most cases unacceptable radon counts are found because radon gas can enter a home from the soil through dirt floors, cracks in concrete floors and walls, floor drains, sumps, joints, and tiny cracks or pores in hollow-block walls.


How Concerned Should We Be?

Although Radon can be emitted by some types of granite, it is highly uncommon. In nearly one thousand different stone slab materials classified as granite in our field, very few of these materials have shown any discernable radon emission, meaning the emissions (if there are any at all) are so minute as to not be detectable by any means. In almost all cases, it can only be estimated that less than one atom of radon is emitted from a roughly 70 cubic foot block of granite per year. This is completely negligible and well below detection by any known method of radioactive analysis. Every granite tested that has conclusively shown a hazardous radon emission rate have been removed from American markets.

Most rock materials used in a home are absolutely safe and many types of rock that are used for countertop surfaces cannot emit radon at all because there are no particles in it which can possibly emit radon. These types of stone include; marble, travertine, onyx, limestone, slate, soapstone, and also the vast majority of materials classified as granite in our industry. These types of rock are absolutely safe and radon free by thier nature.

Formal Radon Testing for Statistical Information

Most formal radon testing has been done on raw granite block. There have been few tests run on finished and sealed granite countertops, and in almost all formal tests on finished granite countertops there has been no discernable radon emissions.

if the Geiger counter squeals then it's gotta be bad... right??

It is very important to recognize that all sorts of products can set off a geiger counter, and therefore can be misconstrued as radioactive. A geiger counter is sensitive to harmful radioactive minerals like: uranium and radium, but also detect harmless minerals such as thorium and even potassium. There are all sorts of products that will set off a geiger counter such as: concrete products, clay bricks, most non-plastic plates and dishes, coal (and the flyash produced in coal-fired power plants), natural gas, phosphate fertilizers used in your garden (ALL of which contain potassium and small amounts of uranium and thorium), and thereby the vegetables grown using those fertilizers. The Border Patrol often catches truck loads of marijuana because it is loaded with radiation producing potassium), all glass made using silica (even eye glasses, wine glasses, mirrors, windows, etc.), and many many more. Almost all of these products do not emit any radon gasses. This is why Gamma measurements made with simple hand-held meters such as geiger counters have absolutely no relationship to potential radon emissions.

When testing for radon in labs there have been a few test results with higer than acceptable results. Usually the granites in question are either more exotic granite materials that have become available relatively recently in the market due to the rising demand for granite, or older granite materials that have been discontinued because of their high radon test results.

The Marble Institute of America is currently undertaking the task of creating a standardized testing protocol for granite to illuminate false information about radon in natural materials and hopefully lead to the removal of the rare harmful granites from the market.

Although Alexander's Stone Art does not provide testing for radon ourselves, we are more than happy to give you information about radon testing, companies that provide radon testing, and samples of any material you are considering so you can have it tested for radon.

Testing Your Home for Radon

There are several companies that will test your home for radon, as well as many manufacturers of DIY (Do-it-yourself) kits. There are two types of DIY consumer testing kits available to check your home for unsafe radon levels: short term, and long term. Both short-term and long-term testing devices are easy to use and relatively inexpensive. Either type can be purchased for about $20.00 through the mail and from hardware stores or other retail outlets. After testing is completed, the kit is simply returned to the manufacturer for analysis. The analysis is usually included in the price of the kit.

Alpha    Track's Do it yourself short term testing kit

Short-term testing (a few days to several months) is the quickest way to determine if a potential problem exists. Charcoal canisters, electret ion detectors and alpha track detectors are currently the most common short-term testing devices. Short-term testing should be conducted with doors and windows shut, preferably during the cooler months of the year when indoor radon is generally somewhat higher.

If a short term result is low it is usually recommended to test again sometime in the future to make certain that the measurement was not conducted at a time that radon levels were at a lull. If a short-term measurement result is high, the best way to determine the annual level is to conduct a long-term test of one year.

Long-term testing can take up to one year and is the most accurate way to test radon. Alpha track detectors and electret ion detectors are the most common long-term testing devices. If a long-term test result is high, homeowners should definitely take action to fix their home as soon as possible.

To ensure the public gets accurate results, the EPA conducts a Radon Measurement Proficiency Program to evaluate companies that make and analyze test kits. It is highly recommended that you should look for a test-kit manufacturer that has successfully completed the Proficiency Program. Most companies indicate approval on the test kit box. In addition, many states require licensing of radon testing companies and contractors. State radon offices have a list of all radon measurement companies that are state or EPA approved. To see a list of approved contractors and companies in the state of Washington see the links at the bottom of this page.

Radon Remediation and Abatement

Typical sub-slab depressurization technique

If your home has been tested for radon and the results are high then radon remediation or abatement is recommended. Radon remediation and abatement includes one or more of the following techniques:

Sealing any cracks in concrete floors, walls, joints, and porous concrete blocking, as well as sealing collets around drains and any other opening that radon gas can seep through into your home.

One of the most preferred methods of radon reduction is "sub slab depressurization" techniques. This method includes the installation of simple vertical piping systems with fans to pull radon gas from the ground under and around your foundation before it can enter your home.

Another method to mitigate radon is using additional ventilation that targets areas in your home that radon can pool.

The use of one or more of these techniques will easily eliminate any radon threat you may have. There are several companies that provide radon abatement services. For more information about radon reduction see the links at the bottom of this page.

The Bottom Line

We have seen varying reports about radon in countertops ranging from those that state that stone countertops are certain to kill you, to those that say that radon is emitted at the most toxic levels from your cement foundation, and that bananas tested for radon emit as much radon as the common stone countertop.

In our search for the truth about radon we have seen some incredibly biased statistics that go so far as to declare that radon is emitted at deadly levels from 100% of stone countertops tested. This specific study has been used as the backbone for natural stone detractors (aka - man-made countertop material manufacturers) and is very misleading for several reasons:

  • All testing was performed on only one type of granite that was already known to contain radon emitting particles and was pulled from the market years ago because of it.
  • The testing did not include any stone of any type that cannot emit radon such as: marble, onyx, travertine, limestone, slate, the vast majority of granite, or any one of the other types of stone that are available on the market.
  • To find a large enough sample of the target type of stone countertops it took a nationwide search to find enough of that material. And this fact was decieving also because by declaring that it was a "nation-wide" study makes it seem more credible.
  • The information gathered in this study is not attributed to any organization, governmental body, collegit group, professionals in the field, or even any credible person who could have prior knowledge about the subject at all.
  • The funding for this study was provided largely by a man-made countertop manufacturer whose product is made from the same ground up materials that their misleading statistics present as 100% deadly.

It takes time to research each study we are exposed to in order to find out how credible the source is, as the least credible sources of information (especially those that are given no source attribution) often rely on our reluctance to research the subject ourselves. Information on any topic presented by any source should be considered suspect until the consumer is reasonably aware of the issues and possible motive for the information being presented.

And The Debate Continues

Alexander's Stone Art is glad to see the rise in concern for the health of consumers over the years and is equally happy to see public scrutiny over issues of household hazard awareness. And although there is still debate over the possibility of radon coming from a countertop, we are comfortable in the knowledge that our products are safe for you, your family, our employees, and the public at large.



"Do not put your faith in what statistics say until you have carefully considered what they do not say."

~William W. Watt






Further Radon Information & Source Materials


- The Marble Institute of America -

The M.I.A. is the leading source of information on standards partaining to natural stone workmanship and practice and the suitable application of natural stone products.

view radon information area

– Snopes.com -

Snopes is the acclaimed front-running site exploring the truth or debunking the falsehood of commonly held misconceptions as well as urban myth and legend.

view radon information area

– MB Stone Restoration –

MB Stone Restoration is a company out of New Jersey that manufactures stone restoration products.

view radon information area

– RadonZone.com –

RadonZone is a leading provider of radon gas testing products.

view radon information area

– Radon.com –

Radon.com is a radon information site sponsored by AirChek inc. A leading provider of consumer radon gas testing kits.

view radon information area


– Dr. Langmuir's Report -

Dr. Donald Langmuir, PhD, Professor Emeritus of Geochemistry, Colorado School of Mines, & President of Hydrochem Systems Corp. responding to information presented in The Journal of the Solid Surface Industry Volume 1 Number 1 (this magazine was created wholly by a man-made solid-surface manufacturer) and included a detracting article entitled "Granite & Radon".

view Dr.Langmuir's Radon Report

– The Consumer Law Page –

this site provides practical information and links to legal counsel for matters of personal injury, negligence, toxic chemicals such as radon, and corporate insurance fraud.

view radon information area

–Environmental Protection Agency–

The EPA is a governmental organization that provides standards in building, waste management, wildlife preservation, as well as consumer protection and health concerns.

Guide to Radon Reduction (pdf) | Radon Zone Map, WA



A note from the author: It is paramount for all of us as consumers to spend as much time as possible to learn about the hazards of the products we consume, especially when we feel we are too busy to spend enough time to find the truth. To rely on information from others when we aren't certain how much they know on the subject encourages the spreading of misinformation, half-truths, and outright deceptions as well as encouraging those who spread these types of falsehoods for mischevous, malicious, monetary, or any other reason.

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