Secondary task method for workload measurement in alarm monitoring and identification tasks

Abstract

The operators who perform alarm monitoring and identification tasks in complex industrial systems, such as nuclear power plants, often suffer from heavy mental workload. Among the many existing mental workload measurements, secondary task method was chosen and examined for that it is sensitive to operator capacity, provides a common metric for different tasks, and easy to carry out, etc. In this study, a paper-based arithmetic secondary task was adopted to measure mental workload of the participants when they were performing alarm monitoring and identification tasks. A two-factor, two-level lab experiment was conducted to examine whether this secondary task method can discriminate different levels of mental workload, and whether it interferes with the primary task. The results showed that though the secondary task chosen in this experiment had good discriminability, its influence on the primary task performance and its interaction with scenario complexity were significant. © 2013 Springer-Verlag Berlin Heidelberg.