Use of probabilistic risk assessment and economic risk at the plant design stage

Probabilistic risk assessment (PRA) techniques and the lessons learned from previous PRA studies were used to evaluate the effectiveness of various design alternatives for the Westinghouse advanced pressurized water reactor design. This evaluation was done successfully at the design state prior to the licensing stage and is probably the first example of such an application for a nuclear power plant design. Three measures of risk were utilized: plant core melt frequency per year, severe fission product release frequency per year, and economic risk to the plant owner in terms of present day dollars.