GAO calls for collaboration on indoor mold guidance.

[Nick Gromicko]

At this point, one may ask "why are we so concerned with the average level over time as opposed to spikes?"

The reason is pure probability. The probability of a cell being damaged and leading to cancer is related to all the radon one is exposed to... not particular spikes. The health effects from exposure to radon are thus cumulative.

[Brian A. MacNeish]

Originally Posted by gromicko

Brian writes:

Uh, your question incorrectly assumes a longer test is more accurate.

Joe F said:
"As a certified Radon Measurement Specialist, I can tell you that your statement is actually incorrect. A 12-month test is most accurate. A long-term carbon electret detector can do it, or an old-fashioned alpha-track detector also fits the bill."

I was simply turning the question back on Joe, the radon measurement specialist. I was using alpha track gear in 1986-7 and knew then that exposure to radon was a cumulative phenomenon. We are trying to ascertain the average level of exposure over the long run and have set a standard for remedial action based an an accepted very low, but still not zero, level of risk!!

The purpose of the long term test isn't to acquire greater accuracy, but rather to gather data over longer periods of time (because as I said in a previous post, radon levels fluctuate). Short term charcoal tests can't test over long periods of time for 2 reasons: The first is that the charcoal doesn't absorb radon, it adsorbs radon (releases as well as collects). Much of the radon it captures in the beginning of the test is gone at the end of the test (and so short term radon tests are biased toward the end of the test). The other is that radon has a short 1/2 life. So the radon the charcoal captures is 1/2 gone after 3.8 days and 3/4ths gone after 7 days.

Most long test kits are actually a less accurate technology but we trade accuaracy for the ability to integrate over long periods of time.

E-Perm electrets are both very accurate and can integrate over long periods of time but only if the electret is fully charged and the radon levels aren't particularly high (so that you don't run out of charge before the end of the test). Consumers can't perform electret tests like they can alpha track though.

IMHO, in regards to radon/asbestos/lead/mould in our houses, the public may be overreacting to the overblown fear has been created by the press and those that have interests in testing/remediation. They are creating hysteria and the "sky-is-falling" reaction with another "problem" every other day.

From my website:

From the MOLD REPORTER (An Online Journal) in an article titled "2002 Air Quality in Review"

•• John Bower, owner, The Healthy House Institute, Bloomington, Ind.:
"The worst thing that has happened to the indoor air quality marketplace in the last year or so is mould. This is because much of the media coverage is designed to sensationalize the topic and frighten the public - so much so, that the word 'mould' always seems to be preceded by the adjective 'toxic'. Thus, homeowners and building managers are scared to death of any minor infestation that might possibly be mould, and they often ignore other health issues, such as combustion byproducts, VOC’s, second-hand tobacco smoke and poor ventilation."

•• Dr. Joseph Lstiburek, president, Building Science Corp., Westford, Mass.: "The biggest news is the insurance people getting out of covering mould claims. This is great news because the easy money is gone. Now we are dealing with real money——yours and mine; insurance money was always viewed as someone else's. Now, attorneys are wary of taking mould cases on contingency. They actually have to work for their money" (and you still have to pay them whether you win or lose- our comment)

•• Larry D. Robertson, president and CEO, Mycotech Biological Inc, Jewett, Texas: "As industry leaders, our failure to have in place an appropriate outlet for public knowledge and education has resulted in gross misrepresentations and misunderstandings of basic Indoor Air Quality fundamentals."

"If you see it or smell it, you do not have to test for it. It is more important to get rid of the mould rather than spend a lot of money trying to find out more about it." (by sampling and identifying the species of mould- our comment) Dr. Joe Lstiburek, P. Eng., Phd..; Building Scientist and principle at Building Science Corporation (Website: www.buildingscience.com)

Why Air Sampling Results Are Undependable
By Jim H. White, Former senior researcher at CMHC

"The problem with most air sample methodologies is that they take a "snapshot" of a highly variable measurement. Several studies have shown that the number of viable spores in a building, at a given location, varies by orders of magnitude over a few days to weeks. This is due to changes in weather (and the way air moves through the building), changes in colony condition (moisture and food availability, energy available for sporulation, and so on), etc. Sampling outcomes are also highly dependent on the specific location of the sampling, especially if the mould is growing."

[James E. Braun, CMI]

Originally Posted by Brian A. MacNeish

•• Larry D. Robertson, president and CEO, Mycotech Biological Inc, Jewett, Texas: "As industry leaders, our failure to have in place an appropriate outlet for public knowledge and education has resulted in gross misrepresentations and misunderstandings of basic Indoor Air Quality fundamentals."

I agree what Mr. Robertson is saying here. If people like Brian would just take the time to get educated in mold. Ignorant people would not paste ignorant stuff from ignorant people on a message board for only the ignorant people will believe.