Development of a maintenance effectiveness monitoring program for CANDU reactors

A procedural program to monitor the effectiveness of maintenance activities was developed for CANDU reactors and, to confirm its applicability, was tested on a CANDU power plant being operated by the Korea Hydro & Nuclear Power Co. The monitoring program is based on a methodology utilizing probabilistic risk information to meet US regulation 10CFR50.65, which is known as the Maintenance Rule. There are many cases in which the Maintenance Rule is applied to Light Water Reactor systems, including PWRs and BWRs. However, it has not been applied to a CANDU Reactor System thus far. In this paper, a procedure to set up a maintenance effectiveness monitoring program is presented with an emphasis on its application to the CANDU system. Relevant solutions to problems that were encountered are introduced to make the program more suitable for the characteristics of CANDU systems. In the end, an application of the program to an operating CANDU power plant is discussed to evaluate the performance status of the plant.

► We develop the first maintenance effectiveness monitoring program in CANDU plants.
► The CANDU design, safety classification and characteristics are considered.
► We develop three more questionnaires for Delphi determination adding to the current questionnaires provided in NUMARC 93-02.
► From the initial evaluation, the program can be a useful tool for monitoring of CANDU safety functions.