Thermo Scientific SAM12, Руководство пользователя

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Issue: 1.0 Calibration Procedure
Thermo Fisher Scientific SAM12 User Manual 10-1
Chapter 10
Calibration Procedure
This section deals in detail with primary system calibration. It
includes background, source and efficiency checks on
individual detectors to check detector balance as well as overall
system efficiency. Primary system calibration by the Health
Physicist is only usually necessary on initial installation and on
a periodic audit basis. More frequent overall system calibration
checks can be quickly carried out by Technician user level
using the “Cal Check” facility (see
Cal Check (page 5-19) ).
For more information regarding the user roles, see Foreword
(page i) and Menu Roles (page 5-5) .
Note: Throughout this section examples are given in Bq.
However, by first selecting nCi’s from the Options Menu (see
Options (page 5-6)
) as the operating units, all values may be
entered in these units. Of course the equations remain
unchanged, though care must be taken to ensure that the
units are consistent.
Calibration Validity
The SAM is capable of undertaking a calibration validity
check. This check will evaluate the number of days between the
last valid (PASS) calibration check. If this number of days
exceeds the maximum acceptable recalibration interval, then
the SAM will put itself “Out of Service” (see
Out of Service
(page 5-62) ).
To define the period between calibrations checks, set the
“Calibration Required Interval” parameter in
Params 1 (page 5-
8) .
If the user “Fails” the calibration check, then this is not treated
as a calibration, and is disregarded when assessing whether the
SAM is within its recalibration interval.
Equipment Required
1. A small radioactive source of known nuclide and
activity, which is found within typical contamination to
be monitored. The SAM is designed to detect activities
down to release levels, as well as quantify significantly
larger activities, up to in excess of 130
μ
Ci (5 MBq).