Information complexity and appropriate interface design in nuclear power plant control rooms

This paper describes factors that cause the information complexity and how to measure the information complexity, and proposes solutions to design a human-machine interface to reduce the complexity of system information in nuclear power plants. The factors include nuclear power control system itself, an improper automation design, new technologies of fully digital instrumentation, control, and human-machine interface that has created tremendous functionality and the price of increased system complexity, and the ill-designed humancomputer user interface. The NASA-TLX and Task COMplexity (TACOM) were adopted to measure the information complexity of screen design and emergency procedure responses, respectively. An overview of the instrumentation and control system of the EPR (Evolutionary Power Reactor), an advanced pressurized-water reactor (PWR), is presented. Its information complexity is discussed and solutions are proposed according to the general principles of humanmachine interface design. We focus on two principles that direct the interface design for the EPR project. The first is to “provide information in a satisfactory manner” to the human operator. The second is to “provide adequate information” to the human operator. This paper is the preliminary report of part of the large multi-year project addressing information complexity problems and interface design in constructions of new nuclear power plants.