David Grammer dg at radata.com
Fri Aug 29 08:31:18 CDT 2008

Additional comments from the Radon Professional Group.
David Grammer  

RAdata, Inc.
27 Ironia Road, Unit 2
Flanders, New Jersey  07836
973-927-7303   973-927-4980 fax

-----Original Message-----
From: International Web Resource for Radon Professionals
Sent: Thursday, August 28, 2008 6:04 PM

This is encouraging to me. I called Ludlum and talked to the technical staff
that does the calibrations. They said they have a radium-radiation-range
that gives them about 5 mR/H to calibrate probes and meters. The end result
is not all that different from when they use Cs-137 which surprised me. 
Typically a Model 19 ( 1" X 1" NaI(TL)) will have 175 cpm per 1 mR/H of
Cs-137 and about 200 cpm per 1 mR/H of Ra-226.

Personally, I would have thought it would have been a bigger difference.

Now keep in mind we are actually seeing readings in the low uR/H- that is,
MICRO-R/H, which is 1/1000th of a mR/H.

Normal background gamma radiation runs 5 to 10 uR/H in my geographical area.

In the western USA, I see readings easily 5X that high.

A few uR/H is insignificant, but IF a reading anywhere near 1 mR/H is ever
found, then some drastic remedial measures will be needed for sure.

A pancake style GM probe is excellent for spotting hot spots and surface
contamination, using betas and alphas. Measuring gammas is not going to be
so easy because of the low levels involved. Certainly RELATIVE readings will
have some merit, as long as a calibrated sample is used to compare.

George Dowell

----- Original Message -----
From: "Geo>K0FF" <GEOelectronics at NETSCAPE.COM>
Sent: Thursday, August 28, 2008 4:34 PM

> David, that sounds very reasonable and thanks for this report. Ludlum is a

> great company to deal with, and if they will calibrate a meter such as the

> Model 19 to radium, it seems to me that this alone would take the 
> uncertainly of readings away, as far as measuring radium is concerned. .
> Your results of 8 to 25 microR are in line with what I had read with an 
> energy compensated microRem meter.
> However as a caveat, unless a full scale spectrum analysis is done, the 
> isotope ratio remains unknown, so the reading may or may not be totally 
> correct. In other words, if ONLY K-40 is present, and the meter is 
> calibrated to radium, the readings are meaningless. Likewise if only 
> thorium is present.
> Like I've posted before, these gamma levels are of scientific curiosity 
> only, and a proper radon survey will reveal the true situation one way or 
> the other.
> George Dowell
> New London Nucleonics Lab
> ----- Original Message ----- 
> From: "David Grammer" <dg at RADATA.COM>
> Sent: Thursday, August 28, 2008 3:35 PM
> Subject: Re: [RADONPROFESSIONALS] Granite
>> To all.
>> The information supplied thru this service in the past few weeks on 
>> granite
>> counter tops is very helpful. Our business is located in New Jersey on 
>> the
>> door step to New York City.
>> We have completed "37 granite scans with radon test" since the news
>> releases. In an effort to offer an honest service we have developed a
>> process and have also considered many of the reported suggestions from 
>> this
>> list to make changes. The granite scan is conducted with a Ludlum Model #
>> 19. These units were calibrated to Ra 226 by Ludlum Instruments on June
>> 27th. We calibrate every 12 months and have primarily used the meters on 
>> the
>> surface of water treatment water softeners or carbon tanks when being
>> removed. State limit for these tanks is 50 microR at 3" off the surface. 
>> If
>> levels are higher the waste disposal is restricted. Upon arrival to the
>> homes we scan all granite surfaces and on a drawing identify variations 
>> in
>> the microR readings. In addition when we conduct these granite screens we
>> require at least 3 additional radon canisters. One radon test canister on
>> the granite counter with the most activity as established by the microR. 
>> A
>> radon canister is placed under a plastic cover (1 cu ft) which is sealed 
>> to
>> the counter. In addition we conduct a canister test on top of the cover,
>> about 6" from the surface. We also place a radon canister in another room

>> on
>> the same floor to determine if levels between the two rooms are similar. 
>> The
>> most important test we place is in the lowest level suitable for 
>> occupancy
>> (most frequently the basement). Some of these scans were in condos that 
>> were
>> as high as the 3rd floor. Those units only had radon canisters within the
>> units living space. The results of the microR meter is never expressed in
>> any units other than what they read. We use the Health Physics Letter to 
>> the
>> New York Times as part of our deliverables to help explain these units to
>> the home owner. I am pleased to say that all of the microR readings were
>> between 8 & 25 microR. The canisters deliver the real information. The 
>> radon
>> canister under the plastic cover usually ranged .4 to 7 pCi/L. None of 
>> the
>> parallel test in the same room were over 1 pCi/L so this was easy to 
>> explain
>> to the home owner. When testing soil outside under an air tight cover we
>> frequently find 200 to 1000 pCi/L in the soil so these granite levels are
>> considered acceptable in comparison. Once these concentrated amounts 
>> trapped
>> in the collector are allowed to be influenced by the volume of air in the
>> room & house the levels quickly reduce to acceptable levels as 
>> demonstrated
>> by the can in a close room.
>> The most important thing I want to tell this group is we found 1 house 
>> with
>> elevated levels of radon from the soil that would have gone undetected. 
>> This
>> house has since been fixed & the home owner is grateful to the NY Times &
>> our company. This is what we are supposed to be looking for. The risk
>> reduction for this family gives me great comfort that I did not take the
>> money of the other 36 without benefit. We will continue to offer this
>> service & will follow updates and ideas how to do our jobs better.
>> It is my opinion that testers should not try to convert radon 
>> concentrations
>> from granite scans and should always conduct real radon tests in the 
>> lowest
>> level of each home along with any other areas they feel appropriate. The
>> NJDEP requires that the radon canister test under the cover be labeled as

>> "
>> This is a diagnostic test only not to be used to when considering the 
>> radon
>> levels for the home.
>> Radon test should be conducted in the lowest level suitable for 
>> occupancy".
>> Good Job All!
>> David Grammer
>> RAdata, Inc.
>> 27 Ironia Road, Unit 2
>> Flanders, New Jersey  07836
>> 973-927-7303   973-927-4980 fax
>> 1-800-447-2366
>> -----Original Message-----
>> From: International Web Resource for Radon Professionals
>> [mailto:RADONPROFESSIONALS at LIST.UIOWA.EDU] On Behalf Of Phil Jalbert
>> Sent: Thursday, August 28, 2008 1:22 PM
>> Subject: [RADONPROFESSIONALS] Granite
>> If you haven't visited EPA's website in the wake of the granite story, 
>> you
>> might want to take a look at the FAQs we've posted and continually 
>> update.
>> http://iaq.custhelp.com/cgi-bin/iaq.cfg/php/enduser/std_alp.php
>> As you'll see from the FAQs, we remain on message with recommending 
>> people
>> test their home's indoor air (not countertops/kitchens) for radon.  Our 
>> most
>> recent additions to the FAQ website address radiation in the workplace 
>> per
>> the current OSHA standard; prompted by calls from fabricators.
>> The senior staff level consensus here is that a protocol on screening
>> building materials generally for radiation is needed most.  Its the 
>> critical
>> first step in estimating risk based on exposure and dose (short of 
>> wearing a
>> personal dosimeter).  Ray Johnson's reply is briefly eloquent in pointing
>> out the source of much of the confusion currently reigning in the media 
>> and
>> elsewhere, i.e., a poor understanding of radiation health physics and in
>> selecting and using equipment.  In fact, we are working up an FAQ on
>> devices, to address public fears being prompted by visuals of the 
>> "clicking
>> Geiger counter."
>> FYI, the ANSI N13 Committee that has jurisdiction for standards 
>> pertaining
>> to radiation protection.
>> See you all in Vegas!
>> Philip P. Jalbert
>> 202.343.9431
>> Radon/SIRG Team Leader
>> www.epa.gov/radon
>> Executive Secretary, Federal Interagency Committee on Indoor Air Quality
>> (CIAQ)
>> www.epa.gov/iaq/ciaq/index.html
>> Subscribe to the CIAQ Listserve! for meeting 
>> notices/minutes/presentations
>> Send an email w/a blank 'subject' line to  ciaq-subscribe at lists.epa.gov
>> Indoor Environments Division (IED)(6609-J) U.S. Environmental Protection
>> Agency 1200 Pennsylvania Avenue, N.W., Washington, DC 20460-0001
>> [DELIVERY Address]
>> Room 431
>> 1310 L Street, N.W., Washington, DC 20005-4113
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