Re: TLD Background subtraction -Reply

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

Ron Shepherd said the following:

> TLD's / film badges or any unit used for permanent tracking of one's dose
> should be stored in an area that receives only background radiation..even if
> this means storing them 'offsite'.
> The control badge is used to alert us to any unusual event that causes the
> badges to read high and a reference point to assess how much exposure to
> subtract.  Some unusual events that come to mind are a rad shipment being
> parked near the badge rack overnight, radiography being performed in the
> building next to where the badges were stored, etc.

I agree completely. It is for that reason I believe that whatever 
subtraction one conducts, that subtraction should be based on 
dosimeters stored with the rest of the personnel badges, when they 
are not worn, and are sitting in the storage area. These "area 
badges" will hopefully cumulate whatever transit dose, natural 
background and any other unexpected exposure that may also be 
accumulated on the personnel dosimeters. In that there is a low 
LLD for the TLD, any small variation in the area badges can result 
either in a false positive, or, a case in which too much is 
subtracted, and there is un-reported dose.

Sandy Perle
E-Mail: sandyfl@earthlink.net 
Personal Website: http://www.geocities.com/capecanaveral/1205

"The object of opening the mind, as of opening 
the mouth, is to close it again on something solid"
              - G. K. Chesterton -
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