Future needs of human reliability analysis: The interaction between new technology, crew roles and performance

Abstract

Human Reliability Analysis (HRA) is an important part of probabilistic risk/safety assessment (PRA/PSA) for nuclear power plants (NPPs). Data has played a central part in HRA, to underpin nominal task probabilities, providing time reliability estimates, and as a basis for multipliers for performance shaping factors (PSFs). New NPPs apply digital instrumentation & control (I&C) systems to support monitoring and control. Will this require new or updated HRA methods and more data as compared to today? We have seen that the combination of the new I&C technology and how it is used by the crew is decisive for the performance of the joint system, comprising the crew and the I&C technology. This paper focuses on the way in which new technology may affect human performance as well as the relation between crew roles, teamwork, and performance. For HRA, two questions are important: What is the impact of teamwork and assigned crew roles on recovery from failure and upset plant conditions? And how should dependency be treated in modern control rooms? This paper discusses these matters based on empirical studies in the OECD Halden Reactor Project and underlines the importance of empirical studies on these topics, since the interactions between new technology, prescribed work processes and actual practices, and crew behavior, are often not obvious. This paper is an extension of a paper presented at the ESREL 2020 – PSAM15 conference.