Radon Gas

What is radon and why is it a concern?

       Radon is a naturally occurring gas that rises from the ground under many homes and can cause serious illness if undetected. It is quite easy and inexpensive to test for (only $99!) and is not typically difficult or costly to fix. Both the Federal and State governments have established levels at which this problem should be fixed and specific methods for achieving an acceptable result.
           Just as the ground is made up of iron, potassium, sulfur, and other elements, it is also made up of uranium and radium which occur naturally in the earth.  As these radioactive trace elements decay, they produce a radioactive gas that percolates up through the soil and then dissipates into the air.  It is a perfectly natural gas-you'll find it in Yellowstone National Park.  The problem arise if we put a house in the way--the gas makes its way up through the interstices in the gravel below the slab, through the concrete slab and into the houisehold air.  Because the gas carries radioactive particulate material with it,  it can do cellular damage to your lungs.

            The EPA and CDC attribute thousands of deaths every year to lung cancer caused by radon exposure. It is considered the second leading cause of lung cancer in the country, and is relatively easy to control.  As a general rule, radon mitigation is performed by cutting a small hold in the floor of the basement or crawlspace, inserting a 4 inch piece of plastic pipe very similar to that used in your plumbing drain system, exiting through a sidewall, inserting a fan and then running a length of downspout up above the eaves to vent the gas into the atmosphere (which is exactly where it would have wound up anyway if we had not placed a house in the way).  These sub-slab depressurization systems are typically extremely effective, and mitigators are required to guarantee to get the level of radon below the EPA and Commonwealth action level of 4pCi/L of air.  These systems typically cost anywhere from $700 to $1500, and can be installed in approximately half a day.  Over all the years we have been testing for radon, having performed many thousands of inspections, we have found that more than one house out of every four tested in our Northern Virginia service area ( 28 percent) has a radon level in excess of the federal standard.  http://www.epa.gov/radon/zonemap.html)

 

What if my house is on a slab, or has a walkout basement?  I have been told that these houses do not have radon problems.

 

            This is a persistent piece of mythology. The EPA recommends testing dwellings up through the second floor, and we have found elevated levels in second-story condos we have personally tested in Northern Virginia.  The only characteristic that governs whether or not elevated levels of radon will be found is the level of radioactive material in the bedrock below the structure.  While clearly, the more elevated and/or ventilated the living space, the lower the radon level is likely to be but simply having  an above ground or walkout basement level has no bearing on the radon levels.

 

 

What if I have a high radon level?  Does that mean I shouldn't buy a house?

 

Joyce (Director of Environmental Services) always says that she wishes she could make buyers understand that they should go and dance in the middle of the street to show how happy they are if the new house needs to be fixed. She's not crazy -- she's right! How is that possible? The truth is presence of radon shouldn't change your mind at all since every house has it and it is in the outdoor air.  It's typically extremely easy to correct and --here's the kicker -- in all likelihood the installation of a mitigation system will leave you with less radon in your air than your neighbors without a radon "problem" PLUS as it pulls all that wet air out from under the slab and vents it the outside it also means that you have a drier, much fresher smelling basement that those neighbors -- it's a wonderful, low-level dehumidifer that doesn't have a bucket that has to be dumped!   We consider radon mitigation systems to be an asset although we don't perform radon mitigation unlike most radon testing firms -- we never benefit from a high test.

 

How do you fix a radon problem?

This is not really a multiple choice question -- sub-slab depressurization is the fix in 99% of the homes with a radon issue.  Sealing cracks and other openings in the foundation is a basic part of most approaches to radon reductions.  The EPA does not recommend the use of sealing alone to reduce radon because, by itself, sealing has not been shown to lower radon levels significantly or consistently and we have many years of test results to confirm that. Sealing cracks and closing sump pits results in level changes that are almost never enough to bring the level below 4.0 pCi/L.  In most cases, systems with pipes and fans are used to reduce radon.  Such systems are called “ sub slab depressurization" and do not require major changes to your home.  The systems prevent radon gas from entering the house from below the concrete floor and the foundation.  Similar systems can also be installed in homes with crawlspaces.  The specifics of the system depend on the design of your home and other factors.  A system typically costs between $700 and $1500.00. You should also test your home again after it is fixed to be sure that radon levels have been reduced and that the system was installed in accordance with E.P.A protocols as required by the Commonwealth.

 http://www.epa.gov/radon

 

I've been told there is more than one way to test for radon.  Are your ways best?

Yes, we believe so. The EPA has validated the E-Perm electret ion method of radon measurement used by All-Pro Services with the highest Test Devices pass rate of all commonly used measurement methods. It has the added advantage of being easy to use and is not as prone to operator error as some other methods such as Continuous Flow Monitors. We also deploy them inside a tamper-resistant cage for added protection. The inexpensive charcoal tests sold in stores are not used by most professional testing firms due to some common inaccuracies, and to the delays and complications inherent in shipping to a third party for analysis. Additonally, they are charcoal which tends to under report radon levels in this marketplace because the charcoal absorbs moisture and adsorbs radon.

 

Does weather affect radon levels?

You bet it does, as does the time of day, whether closed house conditions were maintained, and even the time of the year. The truth of the matter is that the two day testing protocol designed for real estate transactions gives us a snap shot of that two day period and that is it. The EPA would prefer to see all houses tested for a year and that is the gold standard of radon testing. All weather conditions are included, you live the way you live and don't worry about closing doors and windows -- it is simply a much better test. Sadly, it doesn't fit into the process of selling a home. Here's the truth of the matter -- a home should never be over 4.0 pCi/L. If the wind is high the radon  will probably be higher. If the barometric pressure is low it is definitely easier for the gas to rise and the levels will probably be higher. If there is a hurricane the levels will definitely be highter. All of that having been said -- radon gas carries particulate radioactive material that damages your lungs. It should never be over 4.0 in your home. Remember -- 3.9 is not good....we just don't know how to reliably bring levels down any lower than we are now so it is not practical to mandate lower -- unattainable -- concentrations in our homes.

 

But what about rain? Doesn't it increase the radon levels?

If the rainfall is heavy -- several inches -- it would make sense that saturated earth would prevent the gas from percolating up through the soil  leaving only the easier alternative route through the concrete and into your home -- BUT  the only studies on that topic are NOT peer reviewed and there are problems with their methodology so I am not willing to cite them as authoritative here. Small amounts of rain -- a summer afternoon thunderstorm definitely don't affect the levels .....but I cannot definitively give an answer one way or another  --- yet. However -- -it doesn't matter because the radon levels in your home should NEVER be over 4.0 pCi/L.