User experience: does it matter in complex systems?

This paper explores the concept of user experience (UX) within complex systems in the domain of nuclear power production. The specific context is the development of main control room solutions. As UX has become a prevalent concept in human–computer interaction and related research fields, it is a valid question, whether the concept could bring something new to the research concerning complex safety–critical systems also. In this paper, we introduce the concept of UX as an indicator of the users’ subjective feeling of the appropriateness of the proposed tool for the activity. Based on activity theoretical contemplation, we presume that UX is grounded in the feelings and emotions evoked in the usage of the systems and which concern the status of the whole activity. In the paper, a theory-based characterization of UXs in the particular domain is developed based on three general functions of a tool: instrument, psychological, and communicative. We present the operationalization of UX and three studies in which UXs concerning different control room systems during a control room transformation process were followed. Based on the results of the three studies, we find that the significance of UX as an indicator of quality in use lies in the ability to bring the professional users’ experiences, which are embedded in the inner characteristics of the work and not always observable by external evaluators, to the process of designing new systems. Evidence to support the initial background assumption that UXs may concern instrumental aspects of tools was identified in the studies.