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計測機器 Doza RPOGRESSのPDF ユーザーマニュアルをオンラインで閲覧またはダウンロードできます。Doza RPOGRESS 14 ページ。 Spectrometric complex for measurement of activity of alpha-, beta-, and gamma-emitting radionuclides

Doza RPOGRESS ユーザーマニュアル
2) In case that the difference between current and previously measured count rates in at least
one of the checked intervals exceeds the criterion preset in the software, it will warn the user about
change of the background spectrum.
If this is the case, eliminate the reason of increased background and perform two successive
measurements of background in accordance with step 1) above.
In case that during the last background measurements a high background warning will appear
again, results of the calibration should be considered negative with the wording «instability of the
background readings». It is recommended to dispatch gamma-spectrometer for repair.
3) Provided that background change warning does not appear upon completion of acquisition of
the background spectrum (3600 seconds), record the results of background measurements in the
table 4.3.
Table 4.3 - Results of background measurements.
Measured background spectrum
Previously measured
background spectrum
4.5.3.3 Measurement of the working standard activity
1) Perform energy calibration in accordance with section 4.5.3.1 and record results in the
table 4.2.
2) Remove calibration source out of the detector unit and place working standard with
geometry «Marinelli beaker 1 L» instead.
3) Start acquisition of the spectrum in the activity measurement mode by selecting geometry
«Marinelli - 1 L».
Record in the table 4.4 values of the measured specific activity and uncertainty of measurement
results for each of the gamma-emitting radionuclide included in the working standard together with
reference activity of this standard indicated in the calibration certificate for the working standard (after
correction for decay).
Table 4.4 - Results of specific activity measurements of the working standard.
Radionuclide
4.5.4 Processing of the measurement results
1) Calculate the mean value
4.5.3.3).
2) Calculate relative measurement error of the working standard activity by the following
formula
where А
– specific activity of the working standard OISN indicated in the calibration standard
0
(after correction for decay), Bq/kg;
 - mean value of measured specific activity of the working standard, Bq/kg.
1
Measured specific
activity
FVKM.412131.002-03RE
Count rate in the energy intervals, cps
2
3
Uncertainty
of measured activity of the working standard OISN (see
0
100
0
9
4
5
Reference specific
activity
,
6
(4.1)