ALARM-INITIATED ACTIVITIES - AN ANALYSIS OF ALARM HANDLING BY OPERATORS USING TEXT-BASED ALARM SYSTEMS IN SUPERVISORY CONTROL-SYSTEMS

Alarms constitute a significant aspect of the operator-system interfac e in human supervisory control tasks: they have the potential to displ ay information that is of critical importance to overall system safety and integrity. This paper considers the trend toward the use of visua l display terminals for the presentation of alarms, specifically in th e use of scrolling text displays. It is suggested that this form of in formation display may not best serve all aspects of alarm handling. To illustrate why this is so, an analysis of human alarm handling activi ties is presented. The focus on text-based displays and annunciators a llows the authors to concentrate on a number of problems associated wi th the alarm design using a specific medium. From this discussion, the alarm initiated activities model is developed. By considering the act ivities that people engage in when dealing with alarms, an insight is offered into the information requirements that can be used to inform t he design of alarm systems.