| Abstract |
Over the past year, the U.S. National Nuclear Security Administration (NNSA) has sponsored four workshops to compare the probabilistic risk assessments (PRAs) of Soviet-designed VVER power plants. The International Workshop on Safety of First-Generation VVER-440 Nuclear Power Plants was held on May 20 - 25, 2002, in Pieany, Slovakia. A short follow-on workshop was held in Bratislava, Slovakia, on November 5-6, 2002, to complete the work begun in May. Pieany was the location also for the International Workshop on Safety of Second- Generation VVER-440 Nuclear Power Plants (September 9-14, 2002) and the International Workshop on Safety of VVER-1000 Nuclear Power Plants (April 7-12, 2003). The four workshops were held in cooperation with the International Atomic Energy Agency (IAEA), the Nuclear Regulatory Authority of Slovakia (UJD), the Center for Nuclear Safety in Central and Eastern Europe (CENS), and Argonne National Laboratory (ANL). The objectives of the workshops were to identify the impact of the improvements on the core damage frequency; the contribution to the PRA results of different assumptions about events that can occur at the plants; and to understand, identify, and prioritize potential improvements in hardware and plant operation of VVER nuclear power plants . The workshops reviewed the current configuration and safety status of each plant represented, which have all implemented numerous safety upgrades from the original VVER designs. The PRAs were reviewed in order to identify differences among the studies. |
