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Can a homebuyer do their own radon test for a real estate transaction with a self-test kit?

Saturday, June 30, 2018

Yes, you can do the test yourself using two small canisters that you open and leave in the house for a minimum of four days, and costs about half of the average fee for a professional test. The results are as accurate as one done by a licensed radon technician using an electronic monitor.

    The most popular self-test kit is manufactured by Pro-Lab of Fort Lauderdale, Florida. It’s available at Home Depot, Lowes, and many hardware stores for around $10. At the completion of the test, you close the canisters and send them to the lab, along with a $40 lab fee. Test results are available one week from receipt of the test kit at Pro-Lab. If you need it sooner, there is an optional 96-hour turnaround for an additional $20.

When you are doing the 4-day test, the Environmental Protection Agency (EPA) recommends the following test protocol, in order to get the most accurate results:

  1. Close the windows and doors at least 12 hours before starting the test.
  2. Keep the windows and doors closed for the duration of the test, except for normal entry and exit.
  3. Do not conduct the 4-day (short term) test during severe storms or periods of high winds. This may skew the test results upward. See our blog post What factors can change radon test levels up or down? for other things that can mess up the test results.
  4. Follow the testing instructions and record the start time and date.
  5. Place the test device(s) at least 20 inches above the floor in a location where it will not be disturbed and where it will be away from drafts, high heat, high humidity, and exterior walls.
  6. Leave the test kit in place for as long as the test instructions say.
  7. Once the test is finished, record the stop time and date, reseal the device and return it immediately to the lab specified on the package for analysis.

    So why does anybody use a professional radon technician for their test if do-it-yourself is relatively simple? There’s actually two good reasons:

  1. TIME - Take  the 4 days for the test, add 3 days for the canisters to arrive at Pro-Lab by first class mail, plus 7 days for normal lab turnaround, and you’ve got a total of 14 days from start to finish. Most inspection periods are 10 to 14 days, so you would have to place your test canister in the home immediately after signing the sale contract and hope that nothing takes longer than it should to get it done within the 14-day inspection period. Paying the rush processing charge and sending the canisters by overnight express cuts it back to 9 days, if you have a 10-day inspection period, but raises the cost to about $95.
        A professional radon test with an electronic monitor takes 2 days and you have the results same day of completion of test for between $100 and $160.
  2. TAMPERING -  No test device is totally tamper-proof, but the test canisters are extremely vulnerable to fudging by both sides of the deal. The seller can open the windows during the test or place the canisters outside for awhile to reduce the final test number, and the buyer can open the canisters somewhere else for several days before the beginning of the test to increase the test result. Electronic radon monitors keep track of temperature and humidity changes, sense when a door or window is opened and when it is closed, take hourly radon readings, and also note if the machine has been moved. We always tell the seller about the tamper-resistant features before we start a test, but some can’t resist “accidentally” opening the windows for a few hours—which voids the test.

    If you are confident that the seller will not tamper with the test, and you have a 14-day inspection period or longer, a do-it-yourself radon test will save you money. Otherwise, testing by a professional is the way to go.

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Here’s links to a collection of our blog posts about “RADON":

 Is a radon mitigation fan required to be on a dedicated circuit breaker/fuse in the electric panel?

What happens to a radon test result if the windows were opened, the test device moved, or there was any other evidence of tampering during the test? 

Where do I find the Florida laws regarding radon?

Can I test vacant land for radon before building a house? 

Is radon mitigation possible for a condominium?

Do radon mitigation systems require maintenance?

What is the average life expectancy of a radon mitigation system?  

Do older houses have higher radon levels than new houses? 

Can the seller tamper with a homebuyer's radon test to change the results?

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

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

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

What is the danger of radon in well water?

What are the symptoms of radon poisoning? 

Does Florida have radon?

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

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

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

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

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

Will the radon test come back sky-high in a house that has been empty and closed-up for months? 

What is radon? Should I be concerned about it?

Should I buy a house with a high radon level? 

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

What is the operating cost of a radon mitigation system? 

• Should I buy a house with a radon mitigation system?

• Does the buyer or seller of a home pay for radon mitigation when the radon test comes back high? 

What is the probability of having high radon in a Florida house?

• How quickly do I need to reduce a high radon level in my house? 

Does a home inspector check for radon?

What are the problems with underground return air ducts? 

• What is the probability of having high radon in a Florida house?

• What factors can change radon test levels up or down?

    Visit our RADON page for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles.

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