Environmental Evaluation of Control Rooms in Nuclear Power Plants

Abstract

In recent years, it has been expected more than before that the indoor environment of control rooms in nuclear power plants will be made more comfortable without inhibiting function. In order to derive the environmental problems of control rooms in nuclear power plants that should be discussed, the design standards and operators' complaints were investigated. As a result, some problems such as unsuitable lighting, noisy acostics and operators' dissatisfaction with thier enclosed circumstances were derived. In order to improve the indoor environments and to establish comprehensive environmental evaluation methodology, experiments on environmental factors such as indoor view, noise level, glare on VDU and shift time-zone that were thought to be related to the above problems were conducted. 6 subjects' psychological, physiological and behavioral responses to thier environments were measured in the environmentally changeable laboratory, which was mocked up like a control room. Subjects were imposed to do 2 kinds of VDU tasks. From Principal Component Analysis of the experimental results, some psychological, physiological and behavioral indices for evaluating indoor environments were obtained. Furthermore, the relationship between these indices and environmental factors was obtained by Multiple Regression Analysis. The multiple correlation values shows that the environmental factors were most reflected in the psychological evaluation indices. However, other indices are also important because psychological comfort does not always mean good physiological conditions or good task performance. The space functions of the room as a control room and operator's physicological condition should be considered for comprehensive environmental evaluation. The result shows that the introduction of darkgreen louver, potted plants/artificial window and noise reduction are desirable in control rooms.