Re: Unusual element response pattern - Panasonic Badges

["Sandy Perle" <sandyfl@earthlink.net>]

Du Toit,

Very weird patterns, and not normal at all. I am assuming that you have 
provided normalized element responses, which include ECF correction, BKG 
subtraction, RCF correction, and any on-line normalization corrections.

The x-ray pattern looks normal, with the E3 elevation compared to the E1 and 
E2 response. The E4 does NOT look normal at all. The primary way to have an 
elevated E4 response is when the dosimeter is exposed to VERY HIGH 
gamma, Co-60 or greater. For a primary response to Co-60, the E4 response is 
in the range of only 10 to 15% above the E3 response. This does not account 
for what you see. there any possibility that the dosimeters.

I am not aware of any chemical contamination that could affect the CaSO 
elements. Have you checked for the possibility of contaminated lead over the 
E4 elements?  I consider this to be highly unlikely. Also, potential 
contamination from radioactive material over element 4? Again, unlikely.

In summary ... Unless there is a problem with the reader setup, where it is 
looking at the wrong badge type, contaminated lead or contaminated elements 
(all highly unlikely) I am not aware of any factors that would cause the elevated 
E4 responses you are seeing...  Hopefully someone else may have a better 
answer.

------------------
Sandy Perle
Technical Director
ICN Dosimetry Division
Costa Mesa, CA 92626
Office: (800) 548-5100 x2306 
Fax:    (714) 668-3111
  
sandyfl@earthlink.net
sperle@icnpharm.com

ICN Dosimetry Website:
http://www.dosimetry.com

Personal Website:
http://www.geocities.com/CapeCanaveral/1205

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