Human Reliability Analysis using a Human Factors Hazard Model

Abstract

Human Reliability Analysis (HRA) has found application within a diverse set of engineering domains, but the methods used to apply HRA are often complicated, time-consuming, costly to apply, specific to particular (i.e., nuclear) applications, and are not suitable for direct comparison amongst themselves. This paper proposes a Human Factors Hazard Model (HFHM), which builds an HRA method from the tools of Fault Tree Analysis (FTA), Event Tree Analysis (ETA), and a novel model of considering serial Human Error Probability (HEP) more relevant to psychomotor-intensive industrial and commercial applications such as manufacturing, teleoperation, and vehicle operation. The HEP approach uses Performance Shaping Factors (PSFs) relevant to human behavior, as well as specific characteristics unique to a system architecture and its corresponding operational behavior. The HFHM tool is intended to establish a common analysis approach, to simplify and automate the modeling of the likelihood of a mishap due to a human-system interaction during a hazard event. The HFHM is executed commercial software tools (MS Excel and SysML) such that trade and sensitivity studies can be conducted and iterated automatically. The results generated by the HFHM can be used to guide risk assessment, safety requirements generation and management, design options, and safety controls within the system design architecting process. Verification and evaluation of the HFHM through simulation and subject matter expert evaluation illustrate the value of the HFHM as a tool for HRA and system safety analysis in a set of key industrial applications.