RELAP5/MOD3.3 Best Estimate Analyses for Human Reliability Analysis

Abstract

To estimate the success criteria time windows of operator actions the conservative approach was used in the conventional probabilistic safety assessment (PSA). The current PSA standard recommends the use of best-estimate codes. The purpose of the study was to estimate the operator action success criteria time windows in scenarios in which the human actions are supplement to safety systems actuations, needed for updated human reliability analysis (HRA). For calculations the RELAP5/MOD3.3 best estimate thermal-hydraulic computer code and the qualified RELAP5 input model representing a two-loop pressurized water reactor, Westinghouse type, were used. The results of deterministic safety analysis were examined what is the latest time to perform the operator action and still satisfy the safety criteria. The results showed that uncertainty analysis of realistic calculation in general is not needed for human reliability analysis when additional time is available and/or the event is not significant contributor to the risk.

The Integrative Time-Dependent Modeling of the Reliability and Failure of the Causes of Drivers’ Error Leading to Road Accidents

“…Human reliability is defined as the probability of successful completion of a task by an individual without degrading the system, and due to the significant role that human plays in the failures and risk of complex systems, the human reliability assessment (HRA) is seen critical (Zio, 2009;Prosek & Mavko, 2010).…”