Berthold LB 442, Руководство по эксплуатации

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11.3 Shielding and Source
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11.3 Shielding and Source
The shieldings do not include any wearing parts or mechanically
moving parts that under normal operating conditions require main-
tenance. For safety reasons, however, it should be possible any
time to lock the useful beam.
A function check has to be performed in appropriate inter-
vals of half a year. The Radiation Safety Officer has to be in-
formed immediately if any faults on the shielding or a slug-
gish locking mechanism are detected.
If the problem cannot be solved by simple measures such as clean-
ing, stop working with the system until it has been repaired.
As long as the shielding does not show any significant mechanical
damage or strong corrosion, the built-in source will be protected.
Refer to the Radiation Protection Guidelines in Section 12 to check
or replace the source.
The radioactive source used and the measuring system have a ser-
vice life of 5 to 10 years. A source has to be replaced when statis-
tical variations which increase in the course of time become intol-
erably high and any compensation by increasing the time constant
is not permitted, e.g. due to control engineering reasons.
A tare measurement has to be performed any time a source
is replaced!
For information on the design of source and shielding see the tech-
nical documentation and the identity plate (Figure 31).
Source No. :
1234 - 11- 94
MBq
Co-60
400
Shielding
mm
D at e
12.11.94
Pb
98
Dose rate in 1 m distance
5
µµµµ
Sv/h
MODEL LB 7440
Bad Wildbad D-75323
Figure 31: Identity plate