ABSTRACT
The nuclear power industry has always maintained that there could be an explosion within a nuclear power reactor but that in no conceivable circumstances could the blast damage of such an explosion be comparable to the devastation arising from detonation of a nuclear or atomic bomb. Until the Chernobyl disaster, the phrase 'maximum credible accident' (MCA) was commonly used in nuclear power industry to refer to extreme accident situations. Pre-Chernobyl conceptions of the MCA varied somewhat according to type of reactor. In the USA some of early reactors were 'demonstration plants' built to convince utilities of the feasibility and desirability of using nuclear power. In UK and USSR this was less necessary, but in all three countries the size of reactors steadily increased to achieve scale economies. The task of licensing nuclear power reactors in the USA rested with the US Atomic Energy Commission (USAEC) until January 1975, when it became responsibility of its successor, the Nuclear Regulatory Commission (NRC).
