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Welcome to our blog!
We want you to be an informed homebuyer, and each blog post is a question that we have answered for our friends and customers over the years. Hope they help you make a good choice for your next home.

Radon Testing


in Metro Gainesville

48-hour test, results same
day of test completion



when done at same
time as  home inspection

    The premise of the test standard is to replicate the way most people live in their homes: with the windows closed and the HVAC system on. It is a “closed house test.” The occupant of the house can come and go as often as they want, as long as they do not leave a door open.

    While all houses have a small amount of air exchange between the interior and outside, even with the doors and windows closed, opening them will usually reduce the radon level somewhat. Any kind of air exhaust systems also tend to the reduce the radon concentration, although they may possibly increase it and, of course, moving the test device outside will lower the radon reading significantly.

    Examples of passive devices would a charcoal canister or Electret Ion Chamber (EIC). They are both small, simple, and do not require any electric power to operate or have any type of environmental monitoring sensors. The only test result obtainable is the average radon level for the duration of the test. When these systems are used, the single tamper-resistant feature that can be added is securing the device in place with a special tape that shreds when moved to indicate tampering.

    Electronic monitors require power, but have a battery in case the power fails during the test. The one that we use, the Radalink AirCat, is a typical electronic monitor and has the following tamper-resistant sensors:

  1. 1)A movement sensor.

  2. 2)An air pressure sensor that keeps a continuous log of the opening of any doors or windows and the length of time they remain open.

  3. 3)A temperature and humidity sensor that also keeps a continuous log to indicate any temperature or humidity changes.

  4. 4)An hourly radon concentration reading.

    A technician at Radalink, in Atlanta, Georgia, reviews all the sensor data, looking for any indications of changes in the test conditions that would indicate tampering, before releasing the final report to the customer. The result is a test reading that is much less likely to have been manipulated. We occasionally have a test voided by Radalink because of evidence of tampering, and the home has to be retested. It does not happen often, but it does happen.

    While the passive radon test devices are approximately as accurate as an electronic ones, we suggest using a company with an electronic system to be assured of the  most accurate result possible when radon testing for a real estate transaction. Passive devices are just fine for testing your own home or a follow-up test after a radon mitigation system has been installed.

      Not sure whether testing for radon is worth the cost? Read our blog post “How can not testing for radon be an expensive mistake for homebuyers?” before you decide. And if you are considering a do-it-yourself radon test, see our blog post ”Can a homebuyer do their own radon test for a real estate transaction with a self-test kit?” for the pros and cons of doing your own test. 

While we hope you find this series of articles about home inspection helpful, they should not be considered an alternative to an actual home inspection by a local inspector. Also, construction standards vary in different parts of the country and it is possible that important issues related to your area may not be covered here.
© McGarry and Madsen Inspection

Answers to the most Frequently Asked Questions (FAQ) about radon:

  1. What is radon? Should I be concerned about it in Gainesville?

  2. How can not testing for radon be an expensive mistake for homebuyers?

  3. This house has been empty and closed-up for months. Will the radon test come back sky-high?

  4. What are a homebuyer’s options when the radon test comes back high (4.0 pico-curies/liter or more)?

  5. What’s my chance of getting a high radon reading in Gainesville?

  6. How long does it take to get the results of a radon test?

  7. How can I tell if a house has a radon mitigation system?

  8. Do granite countertops emit radon?

  9. Will opening the windows reduce the radon level in a house?

  10. What does a radon mitigation contractor do to lower the radon level in a home?

  11. What is the danger of radon in well water?

  12. Do I need to test for radon when buying a condominium?

  13. What are the symptoms of radon poisoning?

  14. What is the average radon level of indoor and outdoor air in America?

  15. Can a mobile/manufactured home have a high radon problem?

  16. Should homeowners get a pre-listing radon test before selling their home?

  17. For how many years does an old radon test remain valid?

  18. Where does radon come from?

  19. How was it determined that between 15,000 and 22,000 lung cancer deaths each year are caused by radon?

  20. Can stormy weather change the radon in a house?

  21. Do older houses have higher radon levels than new houses?

  22. Do radon mitigation systems require maintenance?

  23. What is the operating cost of a radon mitigation system?

  24. Should I buy a house with a radon mitigation system?

  25. Is radon mitigation possible for a condominium?