Radioactive Walls

[Tad Blanchard <Tad.M.Blanchard.1@gsfc.nasa.gov>]

Regarding Peter Vernigs Post:

        We had a similar experience here.  We decided to change our
monitoring period from monthly to quarterly.  When we did, we found that all
TLDs in one location showed ~10-15 millirem exposures (even the control
badge).  

        Using a scintillation detector we found that the cement block walls
were slightly radioactive.  The TLDs were moved to a partition in the center
of the room and we haven't had a problem since.

        Evidently the threshold of the TLD was not exceeded during the
one-month monitoring period therefore zero doses were reported.
**************************** /^\   /^\ *********************************
Tad  Blanchard              /__ \ /___\    NASA-Goddard Space Flt Ctr 
Nat'l Health Svc, Inc            O             Greenbelt, Maryland     
Sr Health Physics Tech          / \            Phone: 301-286-9157     
                               /___\                                   
                  Tad.M.Blanchard.1@GSFC.NASA.gov                   
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