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Why should I test my home for radon?


Radon is the leading cause of lung cancer in non-smokers.  There are 21,000 - 25,000 (preventable) radon related cancer deaths annually.  The EPA, American Cancer Society, World Health Organization and the Surgeon General all recommend testing every home.  Radon is found in all 50 states. Any home can have elevated radon. On average, 19-23% of all homes in Western MA will show high levels.


All homes have SOME level of radon.  So the question is not "do I have radon in my home" but "is the level of radon in my home at a dangerous level?"  Never rely on your neighbor's results to determine the level in your home.  Results vary widely from house to house.  The only way to know your level is to test.  And remember, all tests ARE NOT EQUAL in terms of reliability, accuracy, timeliness or information.  A flawed test gives you useless information.  Usually a flawed test will show levels as artifically low -- but sometimes they're too high.  See "How do I test" for more information.

Who can test for radon?


Anyone CAN test.  The question is - should they?  Unqualified testers can get misleading results, may not follow EPA guidelines and seldom use reliable equipment.  If anyone "sets a test" and asks YOU to "seal it up and mail it in", they may not be a professional tester and the test may not be valid.  Was the house closed 12 hours before the test was set?  Was the test set in an appropriate location?  Is the proper time elapsed (tests are VERY time sensitive) ?  Is it sealed properly and can you verify the validity of the results?  If you answer no to any of those, you may not want that liabiity.


The EPA, as well as many state Realtor Associations, recommend that you hire a qualified professional when you are buying or selling a home.  Several states require testing by a certified tester.  MA does not require certification, but our tests are evaluated by and our technicians are trained by a Certified AARST/NRRP Radon Measurement Specialist.  We can verify the validity of our tests -- and we're happy to do that.  We are a completely unbiased party.  We aren't selling or buying the property and we don't do mitigation.  We just test and report the radon level.


Only a professional is likely to invest in the technology necessary to get a truly reliable, sensitive test.   An accurate test is priceless -- and a flawed test is dangerous.  The EPA protocol on passive testing calls for " 2 canisters/vials placed side by side".  At the end of the testing period, if the lab results show a difference of more than 25% between them you must discard the test."  Is that the kind of "accuracy" you want to provide to your clients

.? Probably not.  Some studies have shown error rates of 80% and up with collection devices.  Some tests are just returned with no result ("too long in transit").  Not what you want to hear in a time-sensitive real estate transaction.  That's often when we get the call.  And we can usually be there within a day or two.  Better to be proactive in the first place with timely results.


What is the testing protocol ?


In real estate transactions, testing should be done on any level that might be used by the prospective buyer.  For a homeowner, the protocol calls for testing the "lowest normally lived in" area of the home.  The basement is the area with highest concentration of radon.  Many buyers prefer this level to get a "worse case scenario."


Radon levels within a building will change on an hourly basis. Highest indoor levels are found during the winter months when the ground is frozen. For routine "maintenance testing" (which should be done every two years) it is best to test in the winter when the ground is frozen.  Retesting is also recommended after a remodeling project which tightens the envelope and should always be done after a mitigation system is installed.  This can be done once the system has been running for at least two days.


A radon test must be conducted for at least 48 hours.  There is absolutely no way to get a valid test in a shorter timeframe due to the constant changes in the levels.


Protocol calls for closed-house conditions.  This requires that the occupants keep all windows (on every floor) and entry doors closed as much as possible during the test (just as you would in February).  Windows and outside doors should be closed for 12 hours before beginning the test - except for normal entering and exiting.  If windows or doors are open, however, we can set the monitor to start in 12 hours - so the test can be completed as scheduled.  With passive testing you would have to return in 12 hours to begin testing if you intend to produce a valid test - which is generally not what happens.  You should avoid conducting a short-term tests during unusually severe storms or periods of unusually high winds (35-40 mph) as levels can be unusually high during these conditions.


When necessary, air conditioners can be used (on recirculate); in-room fans can be used in rooms away from the device; no whole-house or windows fans should be used.  Leaving windows or doors open can create an air flow pattern which can serve to raise or lower the radon entering the house.  Stabilizing the air within the home as much as possible for the 48 hour teting period allows you to get a more accurate sense of what the annual radon activity is.  The only way to get a more accurate assessment would be to do a 365 day test.  This does not require closed-house conditions.


What kind of testing device is used?


We use only Continuous Radon Monitors. CRMs provide the only form of active testing.  Unlike passive tests, which collect (usually erratically), an active test records the levels.  It records these levels hourly;  clears the data and records the next hour -- 48 times.  At the end of the testing period we have an average based on that data.  This is downloaded and emailed to the customer.  We can also get a reading directly from the monitor at the test site.


CRMs are accurate, reliable, efficient and tamper proof.  They give you a real-time picture of exactly what the levels were during a given time frame.  The detailed chart will show signs of tampering or unusual spikes created by weather or environmental conditions (i.e., nearby construction, etc.).  If we feel there is any question about the results, we will gladly retest free of charge.


Where should home testing be done?


The EPA recommends that testing be done in the lowest level of the home suitable for occupancy or that could be converted to regular living space. This typically represents an area where the greatest radon level will occur.  Never test in a working kitchen, bathroom, laundry room, hallway, closet or crawlspace.  Charcoal devices are especially effected by humidity, air flow, time in place, time in transit and placement in general. CRMs will flag potential problems and are not time sensitive.  Do not disturb any devices during the test.  A CRM will record any motion errors on the chart.  Passive methods have no safeguards.


Because most indoor radon comes from naturally occurring radon in the soil, high indoor levels are more likely to exist below the third floor. This is why the EPA recommends testing all homes at the lowest lived in level or the lowest level that could be converted to regular living space.  In some cases, high radon levels have been found at or above the third floor, due to radon movement through elevators or other air shafts in the building.  If you are concerned about this possibility, you may decide to test multiple levels.


In homes with no basement it is even more critical to know your radon level.  There is no buffer for any radon that is entering through cracks and around the slab, allowing it to enter directly into your living space.  You should test in a bedroom or living area.



What if my home has high levels?


It can be fixed.  Mitigation systems are affordable and effective.  Most can be completely installed in less than a day.  You can find certified, qualified radon mitigators on the AARST website.  Prices typically range from $1200 to $2500, although more sophisticated systems are also available.


Homes with working mitigation systems often have much lower levels than a home with a naturally low radon level.  Most systems will bring your levels down to near or under 2.0 pCi/L.  


Mitigation systems should always be verified for effictiveness with an accurate, sensitive radon test.  You expect a low level - and you should get one.  But low levels with passive testing can mean lack of "collection" -- so there's no real information gained; only time lost.  In every case professional testing is never expensive ... it's priceless.  It's peace of mind .. not a false sense of security.  It just may save a life.

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