Early detection, effective response procedures and prompt action within the area of impact dramatically reduce the consequences.
Download our PDF There are many complex events occurring with some of Japan’s nuclear power plants as a result of the earthquake and tsunami on March 11, 2011.
A Nuclear or radiological emergency is defned as there is, or is perceived to be, a hazard due to: a) The energy resulting from a nuclear chain reaction or from the decay of the products of a chain reaction; or b) Radiation exposure Nuclear Power Plant Accident (defnition) Impact: The threat of or release of radioactive contamination extending beyond the facility to a limited or wide geographic area as driven by prevailing weather systems.
The overall impact varies given the perceived threat and scope of the event, ranging from temporary and precautionary safety guidance for adjacent areas to protective actions of severely contaminated zones.
Of the 33 total backup power lines to off-site generators, all but two were obliterated by the tsunami.
Unable to cool itself, Fukushima Daiichi’s reactors melted down one by one.
“While most studies have focused on the response to the accident, we’ve found that there were design problems that led to the disaster that should have been dealt with long before the earthquake hit,” said Synolakis, professor of civil and environmental engineering at USC Viterbi.
“Earlier government and industry studies focused on the mechanical failures and ‘buried the lead.’ The pre-event tsunami hazards study, if done properly, would have identified the diesel generators as the linchpin of a future disaster.
Synolakis and Kânoğlu report that the Tokyo Electric Power Co.
(TEPCO), which ran the plant, first reduced the height of the coastal cliffs where the plant was built, underestimated potential tsunami heights, relied on its own internal faulty data and incomplete modeling and ignored warnings from Japanese scientists that larger tsunamis were possible.