On guideline for assessing large tsunami countermeasures in Japanese Nuclear Power Plants

Great East Japan Earthquake and subsequent Tsunami caused a nuclear accident in Fukushima Daiichi nuclear power plants (NPPs), which have brought about massive social fear or unrest of NPPs, and the re-start of Japanese NPPs currently being shutdown has not been still allowed although all needed maintenance works have been already completed. The Japan Society of Maintenology organized a special committee to develop a methodology of assessing the safety of Japanese NPPs, which the short-term measures against large tsunami have already been taken after March 11. The vigorous study and discussion resulted in the 'Guideline for Assessing Large Tsunami Countermeasures in Japanese NPPs' so as to assess the robustness of nuclear power plants against large tsunami. This article reviewed outline of the guideline, case studies of good practice NPPs (Tokai Daini, Fukushima Daini, Fukushima Daiichi Unit 5 and 6, Tomari and Hamaoka NPPs; US Diablo Canyon, Swiss Lebstadt and French Chooz NPPs) and comparison of the guideline with EU 'stress test' and US related regulations. (T. Tanaka)