AJAH.418266.007RE
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3.3 Maintenance routine
3.3.1 Maintenance is divided into routine and periodic.
3.3.1 Routine maintenance
3.3.1.1 Routine maintenance is carried out during regular operation; it includes inspections of
detectors for timely detection and elimination of factors which can compromise their operability and
safety.
3.3.1.2 The following main types and periodicity of routine maintenance are recommended:
-
visual inspection ……………………………………………….………..…….. every month;
-
cleaning of external surfaces (decontamination) .…………...……………...…… every year.
3.3.1.3 During visual inspection conditions of cables and connectors and reliability of securing
are assessed.
3.3.1.4 Decontamination of detectors is performed in accordance with work schedule at the
company (facility):
-
external surfaces of detectors are decontaminated using solutions 1) and 2) of the 1.2.22:
after cleaning surfaces using cloth moisten with decontaminating solution it is necessary to wipe
surfaces using cloth moisten with distilled water and then dry using filter paper;
-
cable connectors are decontaminated using solutions 3) of the 1.2.22: additional treatment
with distilled water and drying with filter paper are not required.
Dry cleaning can be performed with any periodicity.
Detectors should be disconnected from the power supply before dry cleaning and/or
decontamination.
3.3.2 Periodic maintenance
Periodic maintenance consists of calibration of detectors.
4 CALIBRATION ROUTINE
4.1 General requirements
Calibration of detectors are performed in accordance with the IEC 61453:2007.
4.2 Preliminary arrangements
Operations performed during calibration and necessary equipment are listed in the table 4.1.
Table 4.1 – List of calibration operations
Operation
Calibration tools and equipment and their technical
characteristics
1 External examination
4.5.1
Visual
2 Testing
4.5.2
Calibration installation UCPN-2M-D (complies with
TU 4362-052-31867313-2005).
Range of reproduced AEDR of neutron radiation –
from 20 to 800
Sv·h
-1
, error ±15 %
PC with technical means for using corresponding port,
with installed “TETRA_Checker” software
3 Determination of basic relative
measurement error of AEDR of
neutron radiation
4.5.3
Power supply with voltage 12÷ 24 V
Not e - It is allowed to use other tools and equipment with similar characteristics ensuring determination of
metrological characteristics of detectors with required precision.