Radon in Granite - What you've been hearing about

We want everyone's exposure to radon to be as low as possible. If it takes someone's concern about their granite countertops to get them to test their home for radon, so be it. But please, be an informed consumer. Read the science about radon in granite before you spend the extra money to test your countertops.

The study that started is called “Radon and Granite” published in Solid Surface, an industry journal. Reportedly, it was written by an unnamed author, whose funding may have come from competitors to the granite industry. I have been unable to find a copy of this original study, so we are unable to comment on the science behind this study.

It does bear noting that with a little on-line research, it is immediately clear that there are two groups at loggerheads over several industry issues: The Solid Surface Alliance and the Marble Institute of America. There appears to be a Shakespearean amount of bad blood between the two groups and they are at vocal polar opposites on this topic. The Solid Surface Alliance says radon in countertops is a serious and significant problem and the Marble Institute of America takes a much less alarmist approach.

Make no mistake: the Solid Surface Alliance does not like granite and sells alternative products. Here is the Solid Surface Alliance information on the granite - use the links on the left to go to their radon information..

Here is what the Marble Institute of America says.

The New York Times article that started it.

Here are independent, non-industry studies of the matter:

• University of Akron - the study
• Heath Physics Society - about HPS - the study

Here are Government and Radon Industry Positions:

• The US EPA Position
• The American Association of Radon Scientists and Technician Position and Testing Strategy

A Very Basic Explanation of Radon’s Health Risk: The Alpha Particle

Radon can be found emanating from granite. It is from the decay of uranium, which is a normal component of granite. Most radon is trapped in the granite and unable to escape, and will not pose a threat to your health. The radon that does escape can emit alpha particles, which are the elements that pose the health risk to humans. Alpha particles are the largest and heaviest radioactive particles and are easily blocked. They are also the most dangerous to human health since they have a high mass, strong absorption, and are ionizing radiation. However, since they are so large and heavy, they can travel only a few centimeters in the air, they easily are absorbed by the skin or plate out on other surfaces and are only a health concern when inhaled or ingested. The primary health risk associated with radon exposure is lung cancer. If you are concerned about health risks stemming from the ingestion of radon, please follow this link.

Our Testing Strategy that includes Granite Countertops - print copy
 
The industry standard does not include sampling areas with granite countertops. Testing that includes device(s) placed on granite is voluntary and done at the client’s request only.
 
To find out the radon levels in the home, a complete survey needs to be done. Ideally, a long-term survey is done (90-365 days) with a homeowner test kit, but a short-term test with a minimum testing period of 48-72 hours (using a test kit or done by a professional) can also be done to take a snapshot of radon levels in the home.
 
A complete survey will include placing on test device in an eligible room on each different foundation in contact with the ground. If a home has a basement, crawlspace, and/or slab foundation, each foundation should have its own device. Devices placed to test crawlspace foundations should be placed in rooms above the crawlspace, not in the crawlspace itself. Our focus is to determine the radon levels where we breathe, and we don’t live in the crawlspace.
 
Place an additional device in the room with the granite countertops.  This device should be placed at minimum 20 inches from the countertop.  Why 20 inches?  First, there aren’t many of us that live with our faces within 20 inches of the countertop, and also, granite is not uniform – you do not want to test one small spot of the counter, you want to test the whole counter’s contribution.  The device placed near the counter should not be encapsulated, nor should it be placed in the cabinet spaces beneath the counters as neither of these are normal conditions or living spaces for the residents of the home.  If there is not another device placed on this foundation already, you may choose to place one in a room away from the countertops to provide a baseline measurement for this foundation.

If it happens that the home has a single foundation and the room with the granite counters is one of the rooms in contact with the ground, two devices need to be placed on that foundation.  One device needs to be placed in the room with the counters and the other should be another room away from the counters.

Once the testing period is complete, the results from the devices should be interpreted as follows:

• If the average of all devices in the home are below 2.0pCi/l, the levels found are considered to be in the Ideal Range per the US EPA and not further action is recommended at this time.
• If the average of any device in the home is between 2.0-3.9pCi/l, the levels found are in the US EPA’s Acceptable Range. You may consider calling a mitigation specialists to determine whether or not the levels could be effectively lowered, and if so, at what cost.
• If any device in the home averages at or above 4.0pCi/l, a radon mitigation specialist should be consulted about reducing radon levels in the home.

 
It is most likely that the highest radon levels will be found in rooms in contact with the ground and the majority of the radon will be coming from the soil beneath the home. The room with the granite may or may not be on that same foundation. With the results of the test, the mitigation specialist will know whether or not the distribution of radon in the home follows normal patterns for having come from the soil. If the distribution pattern is unusual, he will use special diagnostic equipment to investigate the potential sources (with the counters being one) and other possible entry routes of radon coming into the home. He will discuss his findings with you and you can determine the best way to lower the radon levels and your radon exposure throughout your home.