Fire Safety Regulation on High Energy Arcing Faults (HEAF)

Summary: • The knowledge about ensuing fire occurrence in the second phase of HEAF has been accumulated, and it is becoming clear that if arcing time can be shortened, it is possible to prevent fire and to mitigate the consequences of explosions. • In the amended regulatory requirements, prevention of ensuing fire and mitigation of explosion are required. • Research on the scale of the HEAF impact and other factors at the first phase is to be continued, and when new knowledge is obtained, the results will be reflected in the regulatory requirements further, as necessary. – The role of TSO is to make use of research results to actual nuclear safety regulations. – S/NRA/R's HEAF research is a good example of research results that was useful for actual nuclear safety regulations.