AW: [ RadSafe ] DHS Tests of Radiation Detectors Were Inconclusive, Report Says

[Cheng Kit-man]

There can be various ‘forms’ of calibration.  We may need to specify what
form of calibration we are referring to, i.e. whether it is a calibration
against a ‘primary’ standard by a national or international metrology
standardization laboratory, against a ‘secondary’ standard by a competent
metrology standardization laboratory, against a ‘tertiary’ standard or it is
a day-to-day operational ‘consistency’ or ‘performance’ check.  The
different levels of calibration may serve different purposes, are conducted
according to different standardization requirements and provide calibration
outcomes of different uncertainties.

Clement Cheng
Radiation Health Unit
Hong Kong SAR, China

-----Original Message-----
From: radsafe-bounces at radlab.nl [mailto:radsafe-bounces at radlab.nl] On Behalf
Of Doug Aitken
Sent: Friday, March 07, 2008 7:51 AM
To: 'Sandy Perle'; 'Franz Sch?hofer'; 'Brennan, Mike (DOH)';
radsafe at radlab.nl
Subject: RE: AW: [ RadSafe ] DHS Tests of Radiation Detectors
WereInconclusive,Report Says

Sandy et al:
I agree with your definition of calibration (as required, for instance, but
regulation in many instances). But in addition, I guess there is what is
(loosely) called a secondary calibration (or better referred to as a field
check or function check), where the user checks his instrument against a
known reference (normally supplied by the instrument manufacturer to the
user) to verify that it is functioning correctly.

IMHO, anything beyond the normal calibration and a field check with the
user's own references (and NOTHING supplied by the persons evaluating the
instrument performance) would be "fudging"......

Regards
Doug

-----Original Message-----
From: Sandy Perle
Franz,
Your first example is how I define calibration (and NIST does as well).

-----Original Message-----
From: Franz Schönhofer <franz.schoenhofer at chello.at>
........ To make it short: "Kalibrierung" is something which
can be done in the respective laboratory, using sources provided by
institutions or companies tracing their results to some internationally
accepted standards. 
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Doug Aitken     Cell phone: 713-562-8585
QHSE Advisor
D&M Operations Support           
Schlumberger Technology Corporation
300 Schlumberger Drive
Sugar Land TX 77030

Home office: 713-797-0919  Home Fax: 713-797-1757
______________________________________________




_______________________________________________
You are currently subscribed to the RadSafe mailing list

Before posting a message to RadSafe be sure to have read and understood the
RadSafe rules. These can be found at:
http://radlab.nl/radsafe/radsaferules.html

For information on how to subscribe or unsubscribe and other settings visit:
http://radlab.nl/radsafe/