An experimental study of operator activity using an advanced alarm system in nuclear power plant control room

The experimental study has explored the role and the use of an advanced alarm system by means of the analysis of operator visual activity. The study has been carried out in a full scope PWR simulator. There has been analyzed several sources of information: eye movement tracking equipment data, simulator logs, videotapes, and records of on line process expert comments. The participants have been eighteen licensed operators. There were six crews; each crew was composed of reactor operator, turbine operator and shift supervisor. Reactor operator and turbine operator used the eye movement tracking equipment. Three scenarios have been used. Each scenario is composed of several independent failures, lasting around forty-five minutes. There are described the main results from operator’s utilization of the alarm system displays (spatial dedicated displays - alarm tile - and alarm messages on chronological alarm list). There has been considered several aspects, such as number of visual accesses of alarm types and of alarm message areas, role of alarm displays as main information source in the detection of malfunctions, etc. Effects between scenarios and effects of operator role have been analyzed.