Are these radon results fubar?

[William Thacker]

Originally Posted by cduphily

I'll have to find the exact language but PA - DEP gives 2-3 hours leeway between placement/pickup for ease of scheduling. I typically leave my monitors an extra 10-12 hrs longer if I can not pick up close to the drop off time (rural area) ... but some CAN pick up sooner.

If the windows are open, I'll close the house and leave the CRM for 72 hrs + or - 2 hours. I will mathematically remove the first 24 hours of data and average the remaining.

By protocol to minimize the effects of the diurnal changes in radon level, the detector is supposed to be exposed for durations in increments of 24 hours plus or minus 2 hours from 48 hours on.

How do you add 12 hours to your tests? Are you retrieving them at 8:00pm to 8:00am? (assuming you might work from 8:00am to 8:00pm in the field). How do you account for the extra data? Do you remove data? Does your QAP address this situation?

[William Thacker]

Originally Posted by fcarey

I will also from time to time leave a monitor for an extra 12 if I am not sure closed conditions are satisfied when I get there. These monitors only take the last 48 measurements under EPA avg. A short term test is defined as 2-90 days I believe. Don't quote me on that.

The CRMs will record 90 intervals. The average and current values continue to update. On a loss of power, the partial hour value is removed from the average and the current value is lost.

The machine will issue an average based on all hourly results and the EPA average which is with the first four hours removed. The detector must be exposed for 48 hours in order to have the minimum 44 contiguous hours to produce a valid test.

FYI - The co-located test with the machine produced results with a RPD of 1.4%.

[Frank J. Carey]

What were the readings for the co-located test?

[William Thacker]

Originally Posted by fcarey

What were the readings for the co-located test?

The machines were in an undisclosed location deep inside a Hershey chocolate mine.

The readings were 29.0 pCi/L versus 28.6 pCi/L for the suspect CRM

RPD = |(29.0 - 28.6)| ÷ [(29.0 + 28.6) ÷ 2] x 100% = 1.4%

No anomalous data was observed. A difference of 0.4 pCi/L seems fairly insignificant, especially given the accuracy of machine is 25% or 1.0 pCi/L, whichever is higher after at least 24 hours of exposure.

[Chris D. Duphily]

Originally Posted by wthacker

Hi Chris,

For a 48 hour test, you have 48 + 2 hours to pick it up. After that for each additional 24 hours, you have plus or minus 2 hours.

Picking up a detector 58 to 60 hours later is not protocol. Do you certify a 60 hour test?

Bill

Hi Bill... That's not what PA DEP states, you have 48 -2 hours to pick it up. you must document why a 46 hour test was performed but you can do it. Anything over 48 hours is fine it does not have to be in 12 hr increments. Wayne Gemmill of Gemmill Associates, Kelly O. at the PA DEP office and a local mitigation specialist confirmed this... again documentation is key.

[William Thacker]

Originally Posted by cduphily

Hi Bill... That's not what PA DEP states, you have 48 -2 hours to pick it up. you must document why a 46 hour test was performed but you can do it. Anything over 48 hours is fine it does not have to be in 12 hr increments. Wayne Gemmill of Gemmill Associates, Kelly O. at the PA DEP office and a local mitigation specialist confirmed this... again documentation is key.

Hey Chris,

PA DEP is silent on the issue. They defer to the EPA.

Pennsylvania requires all testing and/or laboratory activities be performed in compliance with the following EPA documents:
• EPA-402-R-92-004 - Indoor Radon and Radon Decay Product Measurement Service Protocols, July 1992.
• EPA-402-R-92-003 - Protocol for Radon and Decay Product Measurements in Homes, June 1993.

This is why I asked what your QAP has in it. If you have state approved SOPs, then that is what you follow.

I'll tell you my reasoning and what my QAP uses.

Indoor Radon and Radon Decay Product Measurement Service Protocols, July 1992 allows the grace period of 2 hours it also directs the tester to follow the guidelines of:

Protocol for Radon and Decay Product Measurements in Homes, June 1993 which requires a minimum CR exposure of 48 hours. Any test without at least 44 contiguous hours of data after equilibrium (4 hours) is not a protocol test.

Since it is dated later and I received my initial certification training from someone who helped establish the DEP radon program, I test for 48 hours minimum plus two hours as per my QAP.

That's why I asked about your QAP and what you do with your extra data for a 6O hour test. Also, c'mon...you're not really going back 60 hours after commencing a test are you? At night?

Bill

[Frank J. Carey]

I am curious why that test was so messed up then if the two machines are so close?
Maybe the machine didn't clear out properly. I would be interested to see what Sun has to say about the results.
I can back up Chris on the 12 + hour longer situation. Sometimes If I set a monitor late/ early enough I will be glad to retrieve it if the property is empty. Also went through Wayne's training and he stated that anything over 48 was ok no matter what the increments. The question actually came up during the class. But that was a few years ago.

[William Thacker]

Originally Posted by fcarey

I am curious why that test was so messed up then if the two machines are so close?
Maybe the machine didn't clear out properly. I would be interested to see what Sun has to say about the results.
I can back up Chris on the 12 + hour longer situation. Sometimes If I set a monitor late/ early enough I will be glad to retrieve it if the property is empty. Also went through Wayne's training and he stated that anything over 48 was ok no matter what the increments. The question actually came up during the class. But that was a few years ago.

Hi Frank,

I'll have to go with my radon guru's "tender house" assessment. It was cold and windy that weekend. The last co-located test I perfomed in January had readings of 1.9 pCi/L each. The CRM was beside a wireless router. I just don't know.

Do you remove the data and calculate an average when you expose for longer due to improper closed house conditions at the start of a test?

[Chris D. Duphily]

Originally Posted by wthacker

Hey Chris,

PA DEP is silent on the issue. They defer to the EPA.

Pennsylvania requires all testing and/or laboratory activities be performed in compliance with the following EPA documents:
• EPA-402-R-92-004 - Indoor Radon and Radon Decay Product Measurement Service Protocols, July 1992.
• EPA-402-R-92-003 - Protocol for Radon and Decay Product Measurements in Homes, June 1993.

This is why I asked what your QAP has in it. If you have state approved SOPs, then that is what you follow.

I'll tell you my reasoning and what my QAP uses.

Indoor Radon and Radon Decay Product Measurement Service Protocols, July 1992 allows the grace period of 2 hours it also directs the tester to follow the guidelines of:

Protocol for Radon and Decay Product Measurements in Homes, June 1993 which requires a minimum CR exposure of 48 hours. Any test without at least 44 contiguous hours of data after equilibrium (4 hours) is not a protocol test.

Since it is dated later and I received my initial certification training from someone who helped establish the DEP radon program, I test for 48 hours minimum plus two hours as per my QAP.

That's why I asked about your QAP and what you do with your extra data for a 6O hour test. Also, c'mon...you're not really going back 60 hours after commencing a test are you? At night?

Bill

Bill, I'm stating what I have been told by a state employee and a scientist ; The firm of Gemmill Laboratories offers thirty years of technical management experience in the nuclear science field. More specifically, Wayne J. Gemmill, owner and award winning senior scientist brings to the company over twenty years of experience in product development of radiochemicals along with thirty-one U.S. patents and technical publications. Gemmill Laboratories has also acquired more than twenty years of experience in all aspects of radon science representing all testing and measurement protocols.... The longer the test the better

[William Thacker]

Chris,

I did not question your sources in the least.

I source actual EPA protocol.

All I did was include my own reasoning and asked what you do with your extra data and does your QAP include your SOP.

Additionally, my assertion that a CRM must be exposed for 48 hours minimum is for a real estate transaction single test option only and not for a general radon test. (I had assumed that was understood) After a 4 hour equilibrium period, 44 hours of contiguous data must be obtained to produce a valid test for a radon test performed using the single test option protocol. If someone is certifying a real estate radon test with less than 44 hours in a row of measurement data available, it is not a valid test. I'll stake a bad detector on that.

I agree that for a general radon test performed to assess the need for mitigation, protocol does appear to allow the detector to be exposed for 48 hours plus or minus 2 hours. A real estate transaction radon test is a separate protocol.

[Scott F. Coslett]

William -

Was your testing done in the last few weeks when we had the windy days? What type of heating system was in use?

By the way, I also use Wayne Gemmill (Einstein). It is scary what he knows........

[William Thacker]

PA has codified EPA protocol, meaning EPA protocol is PA law. If your SOP or QAP allows for a 46 or 47 hour measurement, as I have stated before in an earlier post, it is State approved and you are good to go.

Depending on who you ask in a position of authority, you may get some uncertain answers if you ask this question. (I am still researching this subject)

What is not part of a measurement protocol is a test that is not in 24 hour increments, which is why I asked the question about extra data. (No one seems to want to answer that question).

[William Thacker]

Hi Chris,

I just got off the phone after having a very informative chat with Mr. Gemmill. For those that have quoted him saying a 60 hour detector exposure is proper, I would suggest you speak with him directly about this.

Bill

[William Thacker]

Originally Posted by scoslett

William -

Was your testing done in the last few weeks when we had the windy days? What type of heating system was in use?

By the way, I also use Wayne Gemmill (Einstein). It is scary what he knows........

Hi Scott,

Yes, as I explained in an earlier post, it was cold and windy the weekend of the test and a gas furnace and water heater were in use. A subsequent re-test exhibited expected levels for a home with an active mitigation system installed.

I had a lengthy telephone conversation with Mr. Gemmill today. He was quite helpful and I would recommend him. Mr. Gemmill confirmed that a 60 hour exposure is not a protocol test. As far as if a 46 or 48 hour test is proper, he would rather defer to what the position of the PA DEP is, as there is ambiguity in the EPA protocols that govern radon testing. I called the DEP today and so far have received a less than certain reply to that question.

What I do is test for 48 hours and I do not need to worry about how someone interprets the protocol. However, if the DEP accepts a 46 hour CR exposure, no worries for those that do not test for a full 48.

[Frank J. Carey]

Hi Bill,
Sorry that I haven't responded (actually busy the last few days).
I only count the last 48 if I leave it for longer periods. I have only had to do this on two occasions when I first started out. Now I tell the client and realtor to have the house closed or someone is paying double. Haven't had that situation since.
Wayne is something else isn't he?