Paul,
When stored or transported in its holder, what is the sensitivity of the electret to gamma radiation? With little air volume for the gammas to cause ionization in, what level of gamma exposure would effect it?
Thanks in advance,
JimJames L. McNees, CHPAssistant DirectorOffice of Radiation ControlAlabama Department of Public HealthOffice-334-206-5368 Fax-334-206-5387Cell- 334-850-5293--- On Mon, 5/11/09, pkotrappa@AOL.COM wrote:
From: pkotrappa@AOL.COM Subject: Re: [RNPROF] Could this cause false positive radon readingsTo: RADONPROFESSIONALS@LIST.UIOWA.EDUDate: Monday, May 11, 2009, 8:06 PM
I would like to confirm the observation from Dr.Jenkins that the the response of SST or SLT E-PERM in off position, is negligible.While using L chamber E-PERM (LST OR LLT) the standard procedure requires that the electret be shipped separately in electret holder, and screwed to L chamber at the measuremnet location. The response of electret in its holder is similar to that of SST or SLT E-PERM in off position.Paul Kotrappa Ph.D.PresidentRad Elec Inc.
If the Eperm was short-term with the plunger down, in other words in the "off" position, it would not be affected very much, as the volume of the ion chamber is extremely small in that configuration. However, if the Eperm was long-term; i.e. an "L" chamber, then it would be affected. PhilPhillip H. Jenkins, PhD, CHPSenior Health PhysicistBowser-Morner, Inc.Mail: P.O. Box 51 - Dayton, OH 45401Delivery: 4514 Taylorsville Road - Dayton, OH 45424Voice: (937) 236-8805 x248Fax: (937) 233-2024E-mail: pjenkins@bowser-morner.comWeb: www.bowser-morner.com
From: James McNees [mailto:mcneesj@YAHOO.COM]To: RADONPROFESSIONALS@LIST.UIOWA.EDUSent: Mon, 11 May 2009 10:51:35 -0400Subject: Re: [RNPROF] Could this cause false positive radon readings
An error in the story is that cat liter does not emit radioactive traces of uranium, thorium and other natural elements.
Cat liter contains trace quantities of uranium, thorium and other natural elements. No uranium, thorium, or other natural elements are emitted from the cat liter. The radioactive elements stay in the cat liter and emit radiation, some of which will penetrate from beyond the container to the outside of the truck.
If one shipped the electret from an E-perm or an E-perm containing an electret in close proximity to the radiation source it could discharge it some and thus invalidate the future reading. No real concern for charcoal or alpha track detectors, unless one actually contaminated the alpha track with an alpha emitter.
JimJames L. McNees, CHPAssistant DirectorOffice of Radiation ControlAlabama Department of Public HealthOffice-334-206-5368 Fax-334-206-5387Cell- 334-850-5293--- On Mon, 5/11/09, Khudgi wrote:
From: Khudgi Subject: [RNPROF] Could this cause false positive radon readingsTo: RADONPROFESSIONALS@LIST.UIOWA.EDUDate: Monday, May 11, 2009, 9:17 AM
On a recent afternoon, an 18-wheeler with Canadian plates set off a radiation alarm as soon as it crossed the Peace Bridge to Buffalo, the northern border's busiest crossing.
The driver was ordered to pass another monitor and park in an inspection bay. A metal arm swept the truck's top and sides and produced a gamma ray image of the cargo. A guard used a hand-held device to identify the offending isotope. Another grabbed bolt cutters and snapped the truck's rear lock.
He quickly found the problem in boxes stacked inside: scented kitty litter. Clay in cat litter emits harmless radioactive traces of uranium, thorium and other natural elements.
"We see this all the time," said Brad Kovach, a U.S. Customs and Border Protection
http://www.azcentral.com/news/articles/2009/05/09/20090509canadianborder-ON.html?&wired
Kurt Hudgins,
Protech Environmental Services Inc.RN PROF (Subscription changes - archives) - http://list.uiowa.edu/archives/radonprofessionals.html ***** RN LEADERS - http://www.radonleaders.org/ **** RN Linked In: http://www.linkedin.com (Search radon) RN PROF (Subscription changes - archives) - http://list.uiowa.edu/archives/radonprofessionals.html ***** RN LEADERS - http://www.radonleaders.org/ **** RN Linked In: http://www.linkedin.com (Search radon)
NOTICE: This transmission is sent on behalf of Bowser-Morner, Inc. and it maybe privileged, proprietary or confidential. It is intended only for the intendedrecipient. If you are not the intended recipient or a person responsible fordelivering this transmission to the intended recipient, you may not disclose,copy or distribute this transmission or take any action in reliance on it. If youreceived this transmission in error, please notify us immediately by telephone at937-236-8805 ext 228 or by e-mail at postmaster@bowser-morner.com or byfacsimile transmission at 937-233-2016, and please destroy all copies of thistransmission. Thank you.RN PROF (Subscription changes - archives) - http://list.uiowa.edu/archives/radonprofessionals.html ***** RN LEADERS - http://www.radonleaders.org/ **** RN Linked In: http://www.linkedin.com (Search radon) -----Original Message-----From: Phillip H. Jenkins To:
RADONPROFESSIONALS@LIST.UIOWA.EDUSent: Mon, 11 May 2009 11:09 amSubject: Re: [RNPROF] Could this cause false positive radon readings
#yiv308079576 #AOLMsgPart_2_6ed20134-1d8a-47d3-aa27-a87930a12fb3 BODY{font:10pt Tahoma, Verdana, sans-serif;}
If the Eperm was short-term with the plunger down, in other words in the "off" position, it would not be affected very much, as the volume of the ion chamber is extremely small in that configuration. However, if the Eperm was long-term; i.e. an "L" chamber, then it would be affected. PhilPhillip H. Jenkins, PhD, CHPSenior Health PhysicistBowser-Morner, Inc.Mail: P.O. Box 51 - Dayton, OH 45401Delivery: 4514 Taylorsville Road - Dayton, OH 45424Voice: (937) 236-8805 x248Fax: (937) 233-2024E-mail: pjenkins@bowser-morner.comWeb: www.bowser-morner.com
From: James McNees [mailto:mcneesj@YAHOO.COM]To: RADONPROFESSIONALS@LIST.UIOWA.EDUSent: Mon, 11 May 2009 10:51:35 -0400Subject: Re: [RNPROF] Could this cause false positive radon readings
An error in the story is that cat liter does not emit radioactive traces of uranium, thorium and other natural elements.
Cat liter contains trace quantities of uranium, thorium and other natural elements. No uranium, thorium, or other natural elements are emitted from the cat liter. The radioactive elements stay in the cat liter and emit radiation, some of which will penetrate from beyond the container to the outside of the truck.
If one shipped the electret from an E-perm or an E-perm containing an electret in close proximity to the radiation source it could discharge it some and thus invalidate the future reading. No real concern for charcoal or alpha track detectors, unless one actually contaminated the alpha track with an alpha emitter.
JimJames L. McNees, CHPAssistant DirectorOffice of Radiation ControlAlabama Department of Public HealthOffice-334-206-5368 Fax-334-206-5387Cell- 334-850-5293--- On Mon, 5/11/09, Khudgi wrote:
From: Khudgi Subject: [RNPROF] Could this cause false positive radon readingsTo: RADONPROFESSIONALS@LIST.UIOWA.EDUDate: Monday, May 11, 2009, 9:17 AM
On a recent afternoon, an 18-wheeler with Canadian plates set off a radiation alarm as soon as it crossed the Peace Bridge to Buffalo, the northern border's busiest crossing.
The driver was ordered to pass another monitor and park in an inspection bay. A metal arm swept the truck's top and sides and produced a gamma ray image of the cargo. A guard used a hand-held device to identify the offending isotope. Another grabbed bolt cutters and snapped the truck's rear lock.
He quickly found the problem in boxes stacked inside: scented kitty litter. Clay in cat litter emits harmless radioactive traces of uranium, thorium and other natural elements.
"We see this all the time," said Brad Kovach, a U.S. Customs and Border Protection
http://www.azcentral.com/news/articles/2009/05/09/20090509canadianborder-ON.html?&wired
Kurt Hudgins,
Protech Environmental Services Inc.RN PROF (Subscription changes - archives) - http://list.uiowa.edu/archives/radonprofessionals.html ***** RN LEADERS - http://www.radonleaders.org/ **** RN Linked In: http://www.linkedin.com (Search radon) RN PROF (Subscription changes - archives) - http://list.uiowa.edu/archives/radonprofessionals.html ***** RN LEADERS - http://www.radonleaders.org/ **** RN Linked In: http://www.linkedin.com (Search radon)
NOTICE: This transmission is sent on behalf of Bowser-Morner, Inc. and it maybe privileged, proprietary or confidential. It is intended only for the intendedrecipient. If you are not the intended recipient or a person responsible fordelivering this transmission to the intended recipient, you may not disclose,copy or distribute this transmission or take any action in reliance on it. If youreceived this transmission in error, please notify us immediately by telephone at937-236-8805 ext 228 or by e-mail at postmaster@bowser-morner.com or byfacsimile transmission at 937-233-2016, and please destroy all copies of thistransmission. Thank you.RN PROF (Subscription changes - archives) - http://list.uiowa.edu/archives/radonprofessionals.html ***** RN LEADERS - http://www.radonleaders.org/ **** RN Linked In: http://www.linkedin.com (Search radon)
We found the real 'Hotel California' and the 'Seinfeld' diner. What will you find? Explore WhereItsAt.com. RN PROF (Subscription changes - archives) - http://list.uiowa.edu/archives/radonprofessionals.html ***** RN LEADERS - http://www.radonleaders.org/ **** RN Linked In: http://www.linkedin.com (Search radon)
RN PROF (Subscription changes - archives) - http://list.uiowa.edu/archives/radonprofessionals.html ***** RN LEADERS - http://www.radonleaders.org/ **** RN Linked In: http://www.linkedin.com (Search radon)
From Name
James McNees
From Address
mcneesj@YAHOO.COM