[ RadSafe ] Calculations of Radionuclide Activity Concentrations - Reference Request

[ProRadCon at aol.com]

Greetings,
 
I am researching the variations in calculations of activity  concentrations 
for NORM radionuclides based on their isotopic weight  fraction in the 
element, and elemental weight fraction in a solid  media.  For example, the 
calculation of U-238 activity concentration in  soil based on known or dictated 
elemental weight fraction.  I am  seeing some potential variation in the 
parameters provided by professional  colleagues that might lead to percent 
variations in the conversions, and I want  to find any resource(s) that might 
address them, such as a publication  (preferably peer-reviewed).
 
I have performed the conversion calculations for U-238, U-235, U-234,  and 
Th-232 numerous times over the years and have always used the same  
reference.  So I'm not looking for someone to provide  the conversions, I'm looking 
for references showing variations in the  values due to differing references.
 
 
Thank you in advance,
 
Shane  Brightwell, MS, CHP
President
Professional Radiation Consulting,  Inc.
7 Balmoral Drive
Pittstown, NJ 08867
Office: (908)  730-9224
Fax: (720) 294-1153
Mobile: (631) 278-0610
E-mail:  proradcon at aol.com

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