Re: Uranium Uptake Above 10 CFR 20 Limit

[William Lorenzen <LORENZEN_W@A1.TCH.Harvard.edu>]

          From my experience in the uranium production industry there are 
          many jobs/tasks that come up for which engineering controls may 
          not be available.  One example was when a 800 KG vacuum induction 
          furnace would have an "abortion" (a non-technical term used by the 
          workers when a graphite mold would fail during the pouring of the 
          800 KG molten uranium).  I can still feel the floor shaking under 
          my feet as the molten uranium, all 800 KGs, dropped from the 
          crucible into the mold inside a water cooled furnace.
          
          This mess required an individual to have to suit-up and climb 
          inside the furnace (after cooling) and remove all the refractory 
          brick as well as the uranium "abortion".  This exposed the workers 
          to your friend U3O8.  The furnace was only 2.5' to 3' wide inside 
          and stood 15 to 20 feet high.  Not the greatest conditions for 
          applying any engineering controls.
          
          In addition, the company I worked for had no clean-shaven policy 
          so we could never apply for and use respirator protection factors.  
          We would put them in PAPR's and give them a BZA.  Once the BZA we 
          returned and we counted the sample (which was always high from 
          these procedures) we would have to remove the worker for the work-floor and confirm the respirator worked by doing bioassay samples 
          (yes urine AND fecal) to prove no exposure occurred.  Quite a 
          challenge.  I could go on about fires and such but I think you can 
          see this is not an ideal environment.
          
          W. Lorenzen

************************************************************************
The RADSAFE Frequently Asked Questions list, archives and subscription
information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html