Effects of soft control in the nuclear power plants emergency operation condition

Abstract

In addition to the evolution from buttons and switches to the computer-based consoles, the operator may interact with the plant via soft controls. Soft controls are input interfaces connected with control and display systems that are mediated by software, rather than by direct physical connections. However use of soft control may cause unknown difficulties of operation and provide new opportunities of human errors. This study is to investigate the effect of the new interface to human errors in the emergency operation. Based on the emergency operation procedure, the human error modes were identified by using systematic human error reduction and prediction approach. Experiments with 21 graduate students in main control room mockup in the nuclear engineering departments of universities in UAE and Korea were conducted to observe the operators' behavior resulted from the use of new input interface (Emergency safety feature-component control system Soft Control Module, ESCM). Physiological parameters such as electroencephalogram, electrocardiogram and skin temperature were measured to assess the stress level of the subjects. The experimental results showed more human errors during ESCM tasks than non-ESCM tasks. The analysis of the physiological measurements also demonstrated that subjects were in high stress level during the ESCM tasks in comparison with non-ESCM tasks. It is notable that this study was performed with graduate students without consideration of their expertise levels. Different behaviors of the novice and the expert groups were also discussed. (C) 2012 Elsevier Ltd. All rights reserved.