Re[2]: Labware grinder

[epombier@mednet.med.miami.edu]

     I would suggest that you count an aliquot of the last rinse water.
     This is procedure that we use for specialized glassware that is only 
     occasionally used for radioactive procedures prior to returning it to 
     general use.


     Ed Pombier, R.S.O. University of Miami
     epombier@mednet.med.miami.edu
______________________________ Reply Separator _________________________________
Subject: Re: Labware grinder
Author:  radsafe@romulus.ehs.uiuc.edu at smtpmed
Date:    4/12/95 2:39 PM


Since your license amendment doesn't specify HOW you will determine <3X 
sd, how about performing a wipe test for removable contamination.  For 
narrow neck bottles/flasks use long Qtips.  This is how you would clear a 
lab bench for general use, why not waste?  Bill Fendt, U of DE
     
     
On Wed, 5 Apr 1995, Robert Jacobs (612) 962-6530 wrote:
     
>         Our Biology Department has been using disposable labware for 
>         procedures using small quantities of 3H. The 3H is within limits 
>         of sewer disposal, so the PI was washing the labware to dispose 
>         of as common trash. Enter NRC inspector who quoth "nevermore", 
>         since the procedure was not in our license. Then came the 
>         license renewal with a request to allow us to "wash slightly 
>         contaminated disposable labware, and if determined to be free of 
>         contamination following washing (net count less than 3X standard 
>         deviation above the background count for the liquid 
>         scintillation counting system), to dispose of such items as 
>         non-radioactive waste. This authorization will be restricted to 
>         beta emitting radionuclides, primarily H-3.". Then came approval 
>         of the request. ALL OF THIS BEFORE I RECENTLY BECAME RSO. 
>         (Sorry, but the shouting seemed necessary.) 
>         
>         Now to the question, does anybody have an idea how to pull this 
>         off? In order to comply, I have to get a count off of the 
>         labware. This implies that I either have a _very_big_ liquid 
>         scintillation counter (and I don't), or I have to reduce the 
>         labware to _very_little_ pieces to get a sample into the counter 
>         that I have. This would suggest a grinder/chopper of some kind 
>         but I have never seen one marketed for this purpose, or for that 
>         matter, for any purpose.
>         
>         Does anyone have an idea?
>         
>         "New-boy-on-the-block"
>         Bob Jacobs, RSO
>         University of St. Thomas
>         2115 Summit Ave, Mail #PHP 
>         St. Paul, MN  55105
>         
>         Tel (612)962-6530
>         Fax (612)962-6540
>         E-Mail rhjacobs@stthomas.edu 
>         
>         
> 
>