Buyers refute radon results?

–Can buyers/sellers refute radon results if the radon tester is not certified or properly certified?–
Yes, a buyer/seller can refute anything but how likely will their attempt to refute the results succeed if:

  1. They are not certified?
  2. Have InterNachi certification? (This certification is training only and does not mandate device policy & procedures [or tracking thereof], independent proctored industry testing, continuing education [or tracking thereof] nor unique radon industry code of ethics).
  3. They are testing with Charcoal canisters? (easy to manipulate the test results)
  4. The are using a unapproved NRPP or NRSB radon monitor?
  5. They are using an approved NRPP or NRSB approved monitor but it has not been calibrated?
  6. They are an EPA recognized certified radon professional (NRPP & NRSB only) but have not performed a ‘duplicate’ test in the past 10 tests?
  7. They are an EPA recognized certified radon professional (NRPP & NRSB only) but they did not place the device(s) according to AARST (EPA guidance) protocol?

Thank you


Good info Bill.

And, welcome to our forum!..Enjoy! :smile:

Thank you!

Charcoal canisters are no easier to manipulate than other methods. Venting the house throw off any test. On the other hand venting an upper floor can draw in more Radon from a stack effect and make results worse. A 48 hour test is just a basic guideline of whether you should do more testing or not. I had a sellers agent call and give me hell for a result that was exactly 4.0. I told him I just run the equipment I don’t calculate the results.

We live in a world where there is little personal responsibility for anything. Everyone wants to blame someone else (not the way boomers were raised). If someone looses a sale and wants to blame you they don’t need a GOOD reason.

You should, by the way, get a signature that closed house conditions were kept for the entire test or results are not valid.


Manipulation of the testing is a separate conversation but I can say that charcoal canisters are the easiest to manipulate. CRMs can be manipulated by several methods but are easier to identify when comparing the interior/exterior barometric pressures, humidity and temps. Only a seasoned radon professional will known from the CRM data when a crawlspace is being exhausted with a mobile home fan or the house is being pressurize by turning on the HVAC fan or when the return air to the HVAC is supplied with exterior air. (short list)

That is for are, Bob!

I am hoping that this discussion is taken seriously and not lost in side narratives and discussions. I am looking for tangible replies in this “Legislation, Licensing, Ethics & Legal Issues” topics area. Thank you for your cooperation and understanding. If you guys like I can report this in a more general discussion area.

What discussion would you like to have? You asked and answered your own question. If you are referring to Bob’s response, he was spot on. People can refute anything they want.

Problem with closed condition “signatures” is that normal use of the home is OK. There is no reasonable way to control the conditions unless you sleep with your monitoring device on site.

While educating the home owner about what “not to do” you inadvertently teach them how to defeat the test.

In my opinion, the best thing to do is educate your client on the limitations of the test. It is a snapshot in time under current conditions that will give them a better understanding of radon levels at the time of the test.


Thanks Brian…please note the bold words and the ‘if’ part of the question.

How likely? Hmmm, I guess it depends on the lawyer, expert witnesses and the jury. As each one of “your answers” is checked off, the success rate increases.

Testing conditions will always be the weak point in the process because it is not monitored. Bath fan, whole house fans, fireplace dampers, clothes dryers etc. are not under the technicians control.


This is where canister fail: they do not tell the story of the 48+ hours. They only reflect the impact to the charcoal canister contents during the test. Charcoal canisters should only be used when owners of the house want to know and are willing to follow the results. Using NRPP/NRSB approved CRM devices that also record barometric pressure, humidity and temperature help identify situations such as the use of a ‘bath fan, whole house fans, dampers, clothes dryers’ or tampering. With respect to all that I can say that 1 out of 14 tests are inconclusive due to either tampering or situations such as ‘whole house’ fans. I can definitely say that the lion’s share of inconclusive tests are due to tampering with the environment…it is easy to see in the data.

As radon testing professionals we are not just about reading a number of <=2, >2 to <4 or >=4.0…understanding the behavior of the house and the occupants is huge if you buy into radon health information. For example: I did a radon test on an A-frame cabin and the results were just under 4.0. Joe shmoe canister radon guy might say to the the client “It is safe, it is under 4.0”. But the CRMs recorded the story of the 48 hours: the 1st 36 hours were well under 2.0 but the remaining 12 hours were well above 4.0. What questions would you ask Brian? What data would you look at regarding the 1st 36 hours vs the last 12 hours (what additional data do you need to support your written report)? How would you advise the client?

1 Like

In your described situation, the client has options: They can perform a longer radon test to achieve a greater understanding of the radon levels in the home or the EPA states “A radon level below 4 pCi/L still poses a risk. Consider fixing when the radon level is between 2 and 4 pCi/L.” per the EPA’s 2018 “Home buyer’s and seller’s guide to radon”

Sounds like a test question. If you are here to educate, go for it. I will read what you write.

So, what did you advise the client?

1 Like

Your question and enforcement all relates to what kind of requirements your specific state has.


Those typical responses are not professional level radon responses…anyone can read the charcoal canister directions and cite the EPA. But it is not so simple: We should investigate why it was above and below 4.0. So, in this case there was 1) no tempering with the devices because the devices did not indicate that with regards to movement [canister can be moved outside or placed in refrigerators by the occupants] 2) (data to study) the barometric data revealed that the pressure equalized with the exterior at the last 12 hours 3) (data to study) the 1st floor temperature changed slightly 4) no change in humidity. So, I asked the owners what events happened leading up to the last 12 hours…Turns out they had guests who slept on the top floor of the A-frame and the guests got so hot from the stack effect (1st floor was heated to the owners comfort level) that the guests opened the windows but did not tell the owners until they were asked. The 1st floor heated air was moved even faster upwards and out the windows pulling the earth gasses into the house.

The advice to all the occupants of the house: 'Opening the 2nd floor A-frame windows to exhaust the hot air increases the level of radon above the EPA 'Take Action" threshold due to the stack effect and exhausting heated air. Keeping the top windows closed appears to reduce the level of radon to below 2.0.
So, in this case opening windows increased the radon rather than lowering it (wild right)…

In the end it is rather tragic that casual radon testers do not take it seriously to further educate themselves, they are dishing out advice about a health concern…a level 1 carcinogen. The technology exists to better understand the environment but some people still only use canisters. Maybe there is a % of the 22,000 who have died because they received incomplete and inaccurate advice. I do not know but my gut is telling me my client’s health is sacred…to take it seriously and do not settle for decades old approaches when todays technology can save lives.

So what did the Judge have to say about all this?
To me, it sounds as if you got your arse handed to you, and am now looking for support of fellow inspectors to sooth your hurt ego!


Zero states have policy and procedure supporting a sellers position on this matter (it is a legal mater at this point). States that mandate certification, testing and mitigation support only the methods and QA/QC which all exists prior to the seller’s options to refute…

Radon pros, sellers and buyers, in states that require certification, are at less risk of inaccurate or incomplete recommendations since they follow guide lines which support state level department of health policy & procedures. I think this is your point Christopher…but, unfortunately, only a small number of states have certification requirements.

So what did the Judge have to say about all this?
To me, it sounds as if you got your arse handed to you, and am now looking for support of fellow inspectors to sooth your hurt ego!

I call this look before you leap reply…
But here you go: No, that was simple…
Do you have anything constructive to offer?

Yup… looks like I nailed it!!
Good luck.

1 Like

Good thing your able to interview the home owners. Without that interview you would have been left to decipher the data yourself.

Based on the information you provided, my response was appropriate. Longer test or mitigate.

Your question was a set up. You had more info but did not share it. I am beginning to question your motive on this forum.

For the record, I do not use canisters. Best of luck.