What Went Wrong

In spite of the fact that the earthquake was the strongest recorded ever in Japan, and the fifth most powerful in the world since 1900, and another series of aftershocks measuring 7.0 hit almost a month later, the reactors were seismically robust. The earthquake created severe damage to the plant, as well as the rest of the region, but the real problem was the tsunami. 

The earthquake forced the reactors into automatic shutdown, but it also destroyed all six external power supply sources. As designed, emergency diesel generators in the turbine halls kicked on to supply critical electrical power to the reactor cooling 

The Fukushima Nuclear Accident Independent Investigation Commission (NAIIC, 2012a) Chairman Kiyoshi Kurokawa stated. 

System Safety Engineering and Risk Assessment A Practical Approach 

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This result agrees with Computer Project 6-1, but it is not very good, —0.4244 hartrees, as compared to the exact solution of —0.5000, a 15.1% error. What went wrong ... 

Kletz, T.A. (1989) What Went Wrong Case Histories of Process Plant Disasters, Gulf Publishing, Houston. 

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