Re: Disposal of old X-ray systems, PCB's??

[gfeldman@uci.edu (Gerald Feldman)]

Having been through this with an old linear accelerator, I thought I'd add
my 2-cents-worth regarding the PCB contamination problem.

Until the 1970's, PCBs were _commonly_ used as insulators in transformers
and capacitors because they were very stable, had good dielectric
properties, and had high flash points (relative to other insulating
compounds).  In our situation, a small PCB-filled capacitor in the
high-voltage oil tank had leaked years ago and contaminated the surrounding
non-PCB oil.  We were able to get the unit cleaned, but not without some
effort and expense.

Certainly, older x-ray generators used PCB-filled capacitors in their high
tension tanks, and this would be a ready source of contamination to "clean"
non-PCB insulating oils.  

Allowable release limits vary from state to state and will be more
restrictive than the Federal limits. 

If you have any doubts, your best bet to settle the PCB question is to
obtain a small sample of the oil (a few milliliters will do) and submit it
to an AIHA certified laboratory for testing.  Note that there are
restrictions from sending PCBs through the mail, so pick a lab close to you.  

Hope this helps.

(To be PC, I guess I have to say that this is my Opinion, etc, etc. <;-)  )
*************************************************************************
  Gerald Feldman, M.S.
  Radiation Safety Officer
  UCI Medical Center
  101 The City Drive, Rt. 107
  Orange, California  92668
  Voice:  (714) 456-5607
  FAX:    (714) 634-8639
  E-mail: gfeldman@uci.edu 
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