PLiM Lessons After Fukushima

After each severe nuclear incident new safety requirements arise. So the desirable action list gets longer and more specific every time. On the other hand way too many plants have not yet implemented lessons learned from past incidents. The challenge is to prioritize required and desirable measures and implement them incrementally in the sense of continuous improvements. In parallel, there is the plant life management process (PLiM) that gives the framework for single measures. Each remarkable event has to be assessed with PLiM criteria. Could the event have been prevented by implementing the state of the scientific and technical knowledge or has something happened that requires an update of this knowledge? Some details of the Fukushima event are discussed in the paper. These examples demonstrate that safety can be improved just by the application of proven practices which some operators have applied many years before the Fukushima incident. More examples, not only from the Fukushima incident are given in the paper. The conclusion of all these details is that it is necessary to share and implement best practices in a continuous PLiM process rather than defining new safety requirements after single severe incidents. Nuclear safety primarily does not require new knowledge but to take responsibility and implement measures according to available knowledge. This insight links PLiM to the need for an appropriate safety culture, both of which are prerequisite for nuclear safety. The motivation for operators to implement these practices is not only to improve safety but to maximize uptime of a plant and deciding for relevant measures which pays back the money invested in the long run.