Environmental Engineering Reference
In-Depth Information
VVER-1000 NPPs were built, a large part of the originally installed elec-
trical and I&C equipment did not have initial qualifi cation or the qualifi ca-
tion was not certifi ed properly. The issue was recognized in the fi rst safety
reviews (see IAEA, 1992; 1996a; 1996b; 2000). The issue can be resolved in
two steps:
Restoring the initial qualifi cation.
Maintaining the qualifi ed state of equipment.
The maintenance of the qualifi cation means:
Control of the capability of equipment to fulfi l its safety function
through:
periodic testing of systems and components
◦
◦
testing of the equipment following maintenance
◦
results of service routes by maintenance personnel
◦
Development and implementation of a scheduled replacement pro-
diagnostics measurements.
gramme taking into account the requirements for environmental quali-
fi cation in purchasing the new equipment.
Preventive maintenance of the equipment.
The environmental qualifi cation should be reviewed and validated for the
extended operational lifetime. There are different possible outcomes of the
review:
The qualifi cation remains valid for the period of LTO.
The qualifi cation has been projected to the end of the period of long-term
operation.
The effects of ageing on the intended function(s) have to be adequately
managed for the period of LTO via introducing new ageing management
programmes.
Replacement of the equipment.
8.5.4 Synergies: safety upgrading, reconstructions and
power up-rate
There is a synergy between the possibility of LTO and different plant actions
and measures implemented for safety upgrading, power up-rate, improving
reliability and plant programmes. Implementation of the safety upgrading
programme for ensuring the compliance with national and international
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