Two Major Nuclear Emergencies: A Comparison of Chernobyl and Fukushima

Abstract

In this chapter, various aspects of the two major reactor accidents at Chernobyl (1986; Ukrainian SSR) and Fukushima (2011; Japan) are discussed and compared. Both accidents have been ranked at the maximal level of 7 ("Major Accident") at the International Nuclear and Radiological Event Scale (INES). The Chernobyl nuclear accident was caused by an unauthorized experiment in combination with design flaws of the RBMK reactor. The Fukushima nuclear accident was caused by a natural disaster (a tsunami that was triggered by an earthquake). Both accidents released radionuclides mostly of the volatile elements (Kr, Xe, I, Cs, Te), but Chernobyl also released significant amounts of less volatile radionuclides (Sr, Ru, lanthanides, actinides, etc.), mainly in the form of hot particles. Much larger areas have been contaminated by the Chernobyl accident than by Fukushima. The health effects due to the nuclear accidents have been much more severe for the residents of the Chernobyl area than for the residents of the Fukushima prefecture.