About the importance of auditory alarms during the operation of a plant simulator

An experiment was carried out to estimate the effect of auditory alarms on the work of a plant operator in the context of a computer simulation. The process simulator was implemented so that each of eight machines (computer numeric controlled [CNC] robots) produced sounds to indicate its status over time. Each sound was designed to reflect the ‘real-world’ semantic of the actual breakdown event. As many as 32 different auditory alarms plus six normal machine sounds could be played at once. We attempted to design the auditory alarms so that none would be masked (rendered inaudible) by other auditory alarms. Eight students of computer science operated our process simulation program of an assembly line with the eight CNC robots. Relevant information of disturbances and machine breakdowns was given in a visual (test condition 1), and in visual and auditory form (test condition 2). The results indicate that the additional feedback of auditory alarms significantly improves operator performance and increases some mood aspects positively.