Collecting Statistical Data for Security Evaluations Based on Physical Protection Performance Assurance and Testing Methodologies

Recent international recommendations documents, such as the International Atomic Energy Agency’s Nuclear Security Recommendations on Physical Protection of Nuclear Material and Nuclear Facilities, recommend that facility operators develop and implement means and procedures for evaluations, including performance testing. Traditionally, performance testing and evaluations requirements and processes are linked through performance assurance programs and plans, with the evaluation results influencing, through those plans, which subsystems and measures are tested and how they are tested while the results of those tests are used to demonstrate adequate performance as defined by the plans and also provide parameter input for the physical protection evaluations. Relatively simple statistical tests are currently used for maintenance and training purposes, but there has been very limited technical discussion of statistical techniques for using performance data beyond maintenance and training, for example in such areas as effectiveness evaluations. This paper is meant to review existing techniques for collecting and analyzing detection, delay, and response data while noting where there are gaps or limitations (and some errors) in the statistical methods for using that data in evaluations.