DS397 Saf Use Mod RRs with NUSSC comments 18-06-2010

6.18. The reactor manager has the responsibility to ensure that a review of thecommissioning plan is conducted in accordance with the established procedures.6.19. The safety of an implemented modification or experiment should be verified through acommissioning programme involving tests and checks, measurements and evaluations prior toand during implementation of the modification or experiment. The requirements of NS-R-4(Ref. [2] paras 7.42–7.50) are also applicable for the commissioning of a modification orexperiment.6.20. The adequacy of a specific commissioning programme should be reviewed withrespect to the following objectives:– Determination (by measurement under realistic conditions during normal operation aswell as transient conditions) of all reactor characteristic relevant to safety with respectto the changed system;– Demonstration that the unchanged reactor systems (in particular all items important tosafety) are not compromised;– Verification (on the basis of measured data) of the relevant safety constraints;– Provision of additional information and data from commissioning, in order to updatethe safety documentation, the technical documentation and the operating procedures;– Provision of opportunities for familiarization and training of operating andmaintenance personnel;– Adjustment of the reactor systems, affected by the modification or experiment, foroptimum performance.6.21. Special temporary safety provisions or procedures should be developed and exercisedwhen ever necessary during the commissioning process.6.22. The completion of the commissioning process should include a check to confirm thatall temporary adaptations (connections, procedures, arrangements), which were necessary forimplementation, have been removed or cancelled and the facility has been returned to fulloperational status.6.23. The need for a formal approval of the commissioning results and permission foroperation with the experiment or with the modified system should be considered in this stage.31