[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: A Question for Power Reactor Types and others with portal monitors.



Linda,



Thanks for the information.  But I have to say two things about issuing

"passes".  First that is the reason for the question to put a duration in

for security personnel.  Second, it will not be a pass.  Security personnel

are unlikely to just accept a letter or information sheet at face value and

let the person go without any checking.  Personally, though I don't put much

stock in the dirty bomb scenario, I don't think they should.  Hopefully,

personnel will be well trained and have access to appropriate survey

equipment.  A recent response I got indicates that border guards seem to

handle the situation fairly well, asking persons in a bus if anybody has had

a nuclear medicine procedure, have any identified person go through the

portal separately, then the other passengers, then the bus or other vehicle.



But I don't think it is a big stretch of imagination to say we are probably

going to be seeing more radiation survey equipment installed in various

places, say federal court houses, airline passenger terminals, you can guess

as good as I can.  



Which brings up a point, seems to me I read an article either attached or

with a link attached about a lady reporter in Washington D.C. who was

stopped by a Metro [subway] police officer after having had a Nuclear

Medicine diagnostic procedure.  Can anyone tell me where I might of read

that, a reference with date and publication would be WONDERFUL!  I should

have printed it out when I read it.



Anyway I don't think the security people are just going to accept a letter

or information sheet at face value, without some checking.  Anything we can

do to provide a letter or information sheet can easily be duplicated by

someone else, including a call back number.  The answer IMO is good training

for the security personnel and so far, it seems like they have it.



Any opinions expressed in this message are mine alone and do not necessarily

represent those of the Eastern Colorado VA Health Care System, The

Department of Veterans Affairs, or the United States Government.



Peter G. Vernig

Radiation Safety Officer, VA Eastern Colorado Health Care System, 1055

Clermont St. Denver, CO 80220, ATTN:  RSO MS 115; peter.vernig@med.va.gov;

personal peter_vernig@hotmail.com; 303.399.8020 ext. 2447, FAX: 303.393-5026

Alternate fax 303-377-5686

"...whatever is true, whatever is noble, whatever is right, whatever is

pure, whatever is lovely, whatever is admirable, if anything is found to be

excellent or praiseworthy, let your mind dwell on these things."

Paul of Tarsus





-----Original Message-----

From: Sewell, Linda [mailto:LMS1@pge.com]

Sent: Thursday, April 08, 2004 10:32 AM

To: Peter.Vernig@MED.VA.GOV; Radsafe@list.Vanderbilt.Edu

Subject: RE: A Question for Power Reactor Types and others with portal

monitors.





Greetings All,



Nuclear Medicine patients have been an issue at power plants for years since

most of us have portal monitors at the exit to our protected area, not just

the radiologically controlled areas.  We've had 16 folks in our "portal

pass" program in the past year and we employee approximately 1100 people. 



We have found that Tc-99 alarms our portals for 1-3 weeks.  I think it

really depends on how much Mo-99 there is as a contaminant.  



Tl-201 is typically less than a week but is dependent on what it's being

used for.  



I-123 used for thyroid scans is gone pretty quickly, within a few days.  



I-131 for partial or complete thyroid ablation is a problem for 1 - 3 MONTHS

and a dose rate issue for closely located co-workers for a few days.



We are starting to see F-18 and Ga-67 a bit now, but don't really have any

good data yet.  



Another one that is generally only an issue if your lower energy thresholds

are set below 80 KeV or so are the prostate cancer seeds.  The I-125 seeds

are fairly straightforward but the Pd-103 seeds have a significant Zn-65

contaminant which can cause problems.  If the monitors "see" that low, the

seeds are an issue for 1-3 years. 



Several of our workers have indicated that they were setting off the

incoming gate alarms at our local landfill.



A common thread throughout which confuses the matter is that the folks doing

the tests routinely tell the people that we'll never see it or that it will

be gone in just a day or two.  The bottom line is, as well all know, if you

start off with a BUNCH of activity (millicuries) you still have a BUNCH of

activity (from a portal or gate monitor standpoint)  even after 7-10

half-lives.



Regarding Peter's issue on homeland security, it's a very valid point.  As I

recall, I think the current plan is to start having nuc med groups issue the

equivalent of our "portal pass" that indicates that the person has had a

nuclear medicine treatment.  Also, if homeland security sticks with the FEMA

alarm setpoints of 1 uCi that will reduce the impacts.  Most power plants

set their portals to alarm at somewhere around 100 nCi.



Hope this provided some useful information.



Linda



Linda Sewell, CHP

Dosimetry Supervisor

Diablo Canyon Power Plant

MS 119/1/122

PO Box 56

Avila Beach, CA 93424

805.545.4315 (voice)

805.545.2618 (fax)

mailto:lms1@pge.com





-----Original Message-----

From: owner-radsafe@list.Vanderbilt.Edu

[mailto:owner-radsafe@list.Vanderbilt.Edu]On Behalf Of

Peter.Vernig@MED.VA.GOV

Sent: Tuesday, April 06, 2004 12:26 PM

To: Radsafe@list.Vanderbilt.Edu

Subject: A Question for Power Reactor Types and others with portal

monitors.





Group,



I have been pondering the issue of Nuclear Medicine patients setting off

Homeland Security radiation detectors.



There apparently have been scattered incidents so far but NRC published an

information notice on it suggesting a verbal explanation and a business card

be given to patients that could set off such alarms.



I did an impromptu, very quick and VERY dirty test using about 850 uCi of

Tc-99m behind my back [to simulate in the body rather than a point source

and set off waste alarms at about ten feet (3m).



Among the challenges in trying to inform patients and security personnel is

how long a patient may set off an alarm.  We have had personnel here receive

a heart study using Tl-201, usual dose 4 or 5 mCi, trip our waste alarm at

"almost a month" after the procedure.  



I am slow on the uptake but I just realized this is something I have heard

about at power plants and DOE facilities using portal monitoring systems.

Can any of you out there give me any information about how long people that

have had NM studies continue to trip portal monitors.  Any publications that

address this?





Any opinions expressed in this message are mine alone and do not necessarily

represent those of the Eastern Colorado VA Health Care System, The

Department of Veterans Affairs, or the United States Government.



Peter G. Vernig

Radiation Safety Officer, VA Eastern Colorado Health Care System, 1055

Clermont St. Denver, CO 80220, ATTN:  RSO MS 115; peter.vernig@med.va.gov;

personal peter_vernig@hotmail.com; 303.399.8020 ext. 2447, FAX: 303.393-5026

Alternate fax 303-377-5686

"...whatever is true, whatever is noble, whatever is right, whatever is

pure, whatever is lovely, whatever is admirable, if anything is found to be

excellent or praiseworthy, let your mind dwell on these things."

Paul of Tarsus



************************************************************************

You are currently subscribed to the Radsafe mailing list. To

unsubscribe, send an e-mail to Majordomo@list.vanderbilt.edu  Put the

text "unsubscribe radsafe" (no quote marks) in the body of the e-mail,

with no subject line. You can view the Radsafe archives at

http://www.vanderbilt.edu/radsafe/

************************************************************************

You are currently subscribed to the Radsafe mailing list. To

unsubscribe, send an e-mail to Majordomo@list.vanderbilt.edu  Put the

text "unsubscribe radsafe" (no quote marks) in the body of the e-mail,

with no subject line. You can view the Radsafe archives at

http://www.vanderbilt.edu/radsafe/