[ RadSafe ] Reference source re-calibration

[Dahlskog, Leif]

John

The U.K's National Physical Laboratory has a number of useful guides in
the area of calibrations for download from
http://www.npl.co.uk/irmf/publications.html.

I don't recal whether any listed there have a recommnedation for
re-calibration period for the reference sources - I'll leave that for
you to check.

regards

Leif Dahlskog 
Senior Health Physicist
Radiation Health Branch 
Department of Health, Western Australia 
Ph    (+61 8) 9346 2260 
Fax (+61 8) 9381 1423 
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-----Original Message-----
From: radsafe-bounces at radlab.nl [mailto:radsafe-bounces at radlab.nl] On
Behalf Of John G. Hunt
Sent: Friday, 20 May 2005 2:40 PM
To: radsafe at radlab.nl
Subject: [ RadSafe ] Reference source re-calibration

Perhaps Radasfers could help with a question that I have not been able
to
answer:

The problem:
For the rectangular reference sources (tracable) for calibrating
hand-held surface contamination monitors - alpha emitters or beta-gamma
emitters; For sources with long lived radionuclides (Am-241 for
example); For sources that are well looked-after;

The question:
How often do these sources have to be re-calibrated or renewed?    
Is there an international or national or "good practice guide" that
refers to this problem, and to the (re-)calibration interval?

John Hunt.