The interaction between human operators and advanced technology systems has become increasingly complex, particularly with the introduction of automated and semi-automated systems. This complexity is evident in increasing demands for vigilance in what might be regarded as low stimulus environments. Using resource theory as an explanation of the reduction in sustained attention to a task, the present study sought to examine the relationship between cue utilisation and sustained attention in the context of simulated power system control. The participants comprised power system operators from an Australian power transmission organisation, together with university engineering students. Controlling for experience, the results identified a relationship between different levels of cue utilisation and response latency over successive trials on a short vigilance task, consistent with resource theory. At an applied level, the results have implications for the selection and assessment for operators in environments where sustained attention is a necessary requirement.