Preliminary study on internal flooding hazard analysis method for 1000 MWe PWR NPP

Internal flooding is a major risk threatening the safety of nuclear power plant (NPP). Based on the standards and practices of internal flooding protection design for nuclear power plant at home and aboard, the methods of internal flooding hazard analysis (source analysis method and equipment analysis method) are summarized, which are useful for the protection of internal flooding practically. Then the typical example, internal flooding hazard of the representative room of 1000 MWe PWR NPP is analyzed by using the source analysis method, and the analysis result shows that the internal flooding in that room does not pose a threat to the safety of nuclear power plant. The analysis process can also verify the rationality and validity of the method of internal flooding hazard analysis. (author)