Re: "Counting" pump oil

[Esmeralda Party <partye@rockvax.rockefeller.edu>]

Keeping it overnight in the scintillation counter before counting also helps.



At 02:30 PM 11/13/1997 -0600, you wrote:
>Brian,
>
>One technique I have used is to count a series of samples of pump oil,
>say, 1.0, .8, .6, .5, .4, .3, .2, .1 ml of oil per scint vial. Report
>the results as dpm/ml and plot against ml pe sample.  For no
>interferances, you should get a nice horizontal line. If you have
>quenching, chemoluminescence, etc., the value for dpm/ml should approach
>the true value as ml/sample approaches zero.
>
>This is not a very high tech approach, but sometimes is enough. Of
>course you could combust the oil to get carbon-14 and tritium, but this
>is complicated if you are not set up to do it.
>
>good luck,
>Wes
>
>Brian Olson wrote:
>> 
>> Does anyone have a procedure they can share for counting pump oil?
>> Isotopes we are checking for are the usual labeling 'topes.   We want to
>> check the oil before it is sent to recycling, but false positive high
>> counts are really making this a challenging project.
>> 
>> Thanks,
>> Brian Olson
>> Mngr, EH&S
>> Promega Corp.
>> Madison, WI
>> Bolson@promega.com
>
>-- 
>Wesley R. Van Pelt, Ph.D., CIH, CHP                KF2LG
>President, Van Pelt Associates, Inc.     
>Consulting in radiological health and safety.
>mailto:VanPeltW@IDT.net        
>http://shell.idt.net/~vanpeltw/index.html
>
>
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Esmeralda Party
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