Lab Surveys:criteria for Contamination

[Ninni Jacob <Ninni_Jacob@brown.edu>]

Dear RADSAFERS;

I would like to know what criteria you use to determine contamination in
research labs?

1.Do you use greater than 2X or 3X background?
OR
2.Do you use the the NRC guidance of 200 dpm beta and 20 dpm alpha, for
removable and 2000 dpm beta and 200 dpm alpha, for fixed contamination? 
If so, what instruments do you use to determine the dpm, and how are they
calibrated?
For example, how do require the researchers to calibrate their liquid
scintillation counter and/or GM counter for the different isotopes?

Do any of you have strong arguments for or against either of the above
methods?

You can reply to me directly and I will summarise and forward the results
at the end.

As always, thanks for your imput.

Ninni Jacob
Radiation and Biological Safety Officer
Office of Risk Management
Brown University - Box 1914
164 Angell Street
Providence, RI 02912

Tel:401 863 1738 (direct)
    401 863 3353 (main)
Fax:401 863 7676

email: Ninni_Jacob@brown.edu
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