Design of the Human-Machine Interface and the

In this paper, we consider the concept of the impact of an action or human error. We begin from an informal definition of impact as: the effect that an action or sequence of actions has on the safe and successful operation of a system; and develop a quantitative measure of the impact of specified behaviours. It is important that human-machine interface designers should understand the relationship between operator actions and the hazards associated with a system. We demonstrate how impact can be assessed prior to, or in parallel with, the design of the human-machine interface, and show how impact assessments could be used to allow risk analysts to inform designers about the relationship between operator actions and system hazards. To illustrate our approach we present a simple case study. the relationship between operator actions and the hazards associated with a system. In this paper, we consider the concept of the impact of an action or human error, and show how this concept may be useful to interface designers. We begin from an informal definition of impact as: the effect that an action or sequence of actions has on the safe and successful operation of a system. could be generated prior to, or in parallel with, interface design. We argue that an analysis of impact: would complement existing design and analysis techniques by providing valuable additional information for the early stages of design; and that quantification of impact may be more soundly based than attempts to quantify human-error probabilities. We also make some observations on the relevance of impact analysis to the design of autonomous and semi-autonomous computer based control systems. We show how a quantitative measure of impact