Evaluation of the consequences of serious accidents and utilization of such evaluations in various fields of nuclear reactor safety

Serious accidents and those not allowed for in plant design have been the subject of numerous analyses and studies, in particular since the Three Mile Island accident and the appearance of WASH-1400. This is especially true of risk assessments, for which probabilistic methods and models for calculating radiological consequences have undergone considerable development. These calculations are applied to such topics as assistance in site selection (in particular the demographic aspect), the drafting of emergency plans and crisis management, three areas of concern which must be seen as closely linked if nuclear reactor operating risks are to be diminished. The paper reviews current trends in these three areas at the Commissariat a l'energie atomique's Institute for Protection and Nuclear Safety, in the light of the latest developments concerning source terms for pressurized-water reactors and calculations of the consequences of atmospheric transfer. (author)