Re: Radiation Detector Calibrations

["Wesley M. Dunn" <WDUNN@brc1.tdh.state.tx.us>]

Depends on what it is being used for.  If it is for routine, lab
contamination surveys, you're interested in DPMs.  I'd:

1) Check batteries with a DVM;
2) Check HV (some pulse generators will do this);
3) Calibrate the electronics via pulse generator; and
4) Calibrate meter/detector unit (for each detector used) with
   calibrated sources for the appropriate energy ranges (e.g., for
   efficiencies).  You can also use a calibrated Cs-137 source for
   doserate (if you have a compensated GM probe).  You should still
   generate a proper efficiency curve for checking anything other
   than mid-MeV energy gammas.

Remember that counting geometry can make a big difference!

Wes

(Not necessarily an official regulatory remark)

> Date:          Wed, 26 Jun 96 11:38:17 -0500
> Reply-to:      radsafe@romulus.ehs.uiuc.edu
> From:          "Eric A. Goldman" <ea.goldman@baylordallas.edu>
> To:            Multiple recipients of list <radsafe@romulus.ehs.uiuc.edu>
> Subject:       Radiation Detector Calibrations

> Time for a new topic.
>
> I am trying to determine the "best" way to calibrate a survey instrument (i.e. Ludlum
> III.)  There have been two methods proposed: A pulse generator or a Cs-137 Calibration
> source. Any information would be appreciated.
> --
> Eric A. Goldman, B.S.,CNMT
> Baylor University Medical Center
> Department of Medical Physics/Radiation Safety
> Dallas, Texas  75246
> (214) 820-3870

*********************************************************************
Wesley M. Dunn, C.H.P.                     512-834-6688
Deputy Director, Licensing                 512-834-6690 (fax)
(Texas) Bureau of Radiation Control        wdunn@brc1.tdh.state.tx.us
*********************************************************************