Host: The Japan Society of Mechanical Engineers
Name : The 30th International Conference on Nuclear Engineering (ICONE30)
Date : May 21, 2023 - May 26, 2023
After the accident at the Three Mile Island nuclear power plant in the United States, the probabilistic safety assessment (Probabilistic Safety Assessment, referred to as PSA) in the nuclear industry began to boom. Although nuclear power plants have various safety designs, reactor core damage accidents can still occur. Using PSA technology can help nuclear power plants identify weak links and reduce the chance of core damage accidents within a reasonable range. The NRC believes it is necessary to establish a mechanism to monitor the effectiveness of maintenance operations at nuclear power plants to ensure that critical safety systems are able to perform their assigned safety functions. In July 1991, the NRC issued 10 CFR 50.65 Maintenance Rules (MR), titled "Requirements for Monitoring the Effectiveness of Nuclear Power Plant Maintenance." In 1993, the Electric Power Research Institute (EPRI) issued NUMARC 93-01 "Industry Guidelines for Monitoring the Effectiveness of Nuclear Power Plant Maintenance". On July 10, 1996, the maintenance rules came into effect. Effective maintenance closely related to nuclear power plant maintenance and operation and nuclear safety can minimize the number of transient events due to system, structure and component (SSC) failures. To evaluate and/or monitor the effectiveness of maintenance and operations, Maintenance Regulations (MR) use probabilistic safety assessment (PSA) techniques to ensure that each system is performing well. A peer-reviewed PSA model is an appropriate tool for conducting (a)(4) evaluations. In general, risk assessment staff should evaluate the risk of planned maintenance activities (such as preventive maintenance) on the previous day or two and ensure that potential risks are acceptable and controlled. If certain emergencies are likely to change the conditions of a previously (or planned) evaluation performed, PSA staff should re-evaluate the risk due to the change in conditions if it falls within the scope of the MR. Depending on the results of the evaluation, planned maintenance activities may need to be suspended or rescheduled.
