Abstract
It is known that alarm systems play important roles in the monitoring and controlling of safe operation in advanced main control room. In other words, there exists high relationship between the safety of nuclear power plant (NPP) and the alarm system design. Therefore, the main purpose of this study is to discover the critical amount of alarms to improve operation performance and human-system interaction. Hence, the four levels of alarms quantity scenarios are designed in the experiment based on structured interview, procedures studies, observations, and issues integration. And the hypothesis in this study is that the number of alarm significantly affects operation performance. In each level, participants have to follow the Abnormal Operation Procedure (AOP) and deal with the events. The alarm display included both abbreviations of alarm label on WDP and abnormal state descriptions on VDUs. Then, the optimal quantity of alarms is suggested after analyzing primary and secondary task performance, situation awareness (SA), and mental workload. The results of this study indicated that the optimal alarm number is five, and it is necessary to display both alarm abbreviations on WDP and alarm descriptions on VDUs. Finally, in order to enhance operating safety in automation system, three suggestions of alarm display design in automation system are proposed: (1) Maintain fewer than five alarms for monitory simultaneously, (2) Integrate correlative alarms, and (3) Short-term and descriptions of alarm should be displayed on VDUs.