“On-Line Maintenance (OLM)” with effective utilization of IRIDM (Integrated Risk-Informed Decision Making) can contribute both plant safety enhancement and plant operability improvement simultaneously in nuclear power plants (NPPs). At the stage of planning and implementing OLM in NPPs, all workers should recognize the risks, and establish risk management actions. These processes are very important to enhance plant safety. OLM can contribute leveling maintenance work loads which used to be accumulated during outage. The more experienced workers can lead maintenances, the more technical transfer from experienced worker to young worker will be made. As OLM has already had excellent results in the United States and Europe, we shall promote implementation of OLM in NPPs in Japan.
