Análisis de incidentes operativos en sistemas complejosactuación humana ante alarmas

Abstract

The research has been conducted to explore the role and the use of alarm system in an advanced control room in the process control domain. Alarm system supports the operator to maintain variables within normal operating range in the safety margins of the plant. The alarms are a vital element in the process control. In the theoretical part of the research project, before starting with aspects related to the alarm system in the process control, initially we characterize the control room and the simulators in the process control, the approach to the different types of design (conventional versus advanced), issues of the introduction of new technologies in the control room and the relevance of the concept of operation of the plant. Second, the role of the operator in the control room is explained, the operator’s functions and the tasks assigned to them based on the plant states during diverse operating conditions, and the capabilities and limitations of the human being relevant for a user-centred design approach. A state-of-the-art review covers the basic philosophy of an alarm system in the control room, the concept of alarm and alarm system, the functions of the alarms, and the uses of the alarm systems. Next follows a review of the regulatory approach on the incorporation of human factors principles in the control room and in the alarm system design as well as a description of principles, guidelines and recommendations, standards and style guides. Then, the primary problems with alarm system design, that operators and organizations need to handle, are reviewed for the nuclear industry and other environments. Next, some incidents and accidents that happened in different domains are described, highlighting the role of the alarms in the events. The features of the alarm system, focus on the alarm presentation media in a conventional control room versus an advanced control room, are the subject of one of the chapters. The last chapter of the theoretical part presents a literature review of the state of the art for alarm systems in relation to the hypotheses and the research questions of this research project. The bases for formulating of the thirteen hypotheses comes from previous studies described in the state-ofthe- art review and from our experience in the design and evaluation of the interface of alarm systems in control room simulators of the nuclear field. The primary focus of the research is on the presentation of alarm information and how operators use the alarm system in the control room. In the experimental part, initially the experimental method of the study is described. The visual activity of operating crews was analyzed with experimental design which comprises between designs and within designs in different scenarios. Several sources of information data collection were employed in the study, such as eye movement tracking equipment data, simulator logs, videotapes, and records of on line process expert’ comments during the simulations. Six professional crews of nuclear power plants in operation participated (eighteen licensed operators), and each crew was composed of reactor operator, turbine operator and shift supervisor. The reactor and turbine operators used the eye movement tracking equipment. Therefore, the crew data were averaged over the reactor and turbine operators, not including the role of supervisor or other potential members of the shift...