Re: Medical waste held for decay -Clarification

[mdater@nexstar.com]

Joelle,
At your facility  if you hold  for example 32p for 10 half lives . You
might then survey (dry solid ) waste with a  ludlum 44-9 pancake detector
or other suitable  detector before release to public waste stream. You
might use "non-detectable" as your guide. I mean by this if  you can detect
any radioactivity above background you could hold for another half live .
You should note that when you are decaying a large activity of for example
32P, Chances are that you will indeed have to hold this waste for more than
10 half-lives to get back down to background (non-detectable) levels. For
Liquid waste (32P)  this can be detected by counting in an LSC.  You could
run a blank sample to get the background level  then the waste sample , in
this way you can determine if there is any activity left.

Mark Dater
NeXstar Pharmaceuticals, Inc.
2860 Wilderness Place
Boulder, CO. 80301
Work phone: (303) 546-7703
Fax: (303) 444-0672
E-mail mdater@Nexstar.com
These are my comments and questions and not those of my employer.



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