42 Risk & Emergency Zoning around Nuclear Power Plants and Other Major Hazardous Industrial Installations (PSAM-0365)

This paper analyses the background and current status of the information basis leading to the definition of risk and emergency zones around Nuclear Power Plants (NPPs) in different countries in Europe and beyond. Although dependable plant-specific Probabilistic Safety Assessment (PSA) of Level 2 and/or Level 3 could in principle provide sufficiently detailed input to define the geographical dimension of a NPP's risk and emergency zones, the analysis of the status in some European and other countries shows that other, “deterministic” approaches using a reference accident are actually used in practice. Regarding use of Level 2 PSA for emergency planning, the approach so far has been to use the Level 2 PSA information retrospectively to provide the justification for the choice of reference accident(s) used to define the emergency plans and Emergency Planning Zones (EPZs). Where a reference accident approach is used based on the Level 2 PSA information, consideration needs to be given to the number of reference accidents that need to be defined in order to characterise the severe accident progression and release characteristics of the plant. There are significant differences in the EPZs that are defined in different countries. These range from less than 10 km up to 80 km in different countries. Reasons for these differences are discussed.

Based on currently used decision criteria in defining NPP emergency zones in some European countries, issues such as definition of EPZ, information to the public in the event of radiological emergency and emergency protection measures are screened and a comparison between different countries is made.

There is a striking contrast in the extent of using probabilistic information to define emergency zones between the nuclear and other high risk industry sectors, such as the chemical process industry, and the reasons for these differences are not entirely clear, but seem to be more related to risk perception than actual risk potential. Therefore, there is a strong need to be able to communicate risk information to the public both before and following an accident. In addition, there is a need to educate the public on that they can understand risk information in a comparative sense. Finally, based on the consensus discussions at a recent JRC/OECD International Seminar on Risk & Emergency Zoning around NPPs, a set of recommendations is given in the areas of a more comprehensive use of the available risk information for risk zoning purposes, risk communication, and comparative (energy) risk assessment.