Regional Basic Professional Training Course in Korea

Regional Basic Professional Training Course (BPTC) on Nuclear Safety
coolant system chemistry section. Actual limiting conditions for operation are stated in
the example.
Limiting conditions for operation are defined as, 'requirements needed to be fulfilled to
insure controlled operation of the NPP'. The following content regarding the LCOs state
the action items to be taken when an incident in which the LCOs cannot be satisfied. The
NPP must be shutdown if the LCO requirements continually fail to be fulfilled. The
technical background or the technical basis related to the LCOs is also stated. The items
of inspection to satisfy the LCOs are stated in a different chapter of the operational
technical specifications.
There are a total of four operation modes and these modes have been defined according to
temperature and reactivity. The first mode is the cold shutdown, in which the temperature
is less than 200℉ and the reactor is in a subcritical state that is approximately 1%△K/K.
The second mode is the hot shutdown in which the coolant temperature is between 200℉
and 525℉ and the reactor is in a subcritical state that is approximately 1% △K/K. The
third mode is the hot standby, in which the reactor power is less than 2%, and the coolant
temperature is higher than 525℉. The final operation mode is the power operation in
which the reactor power is more than 2%.
3.1.5 CHEMISTRY
Applicability
Applies to the limiting conditions of reactor coolant chemistry for continuous operation
of the reactor.
Objective
To protect the reactor coolant system from the effects of impurities in the reactor
coolant.
Specification
Table 10.4 Initial Operational Technical Specifications Writing Format
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