Fire risk analyses have shown that fires can be a major contributor to nuclear power plant risks (OECD 2000). They are also known to be very demanding for the control room operators due to the complexity and uncertainty related to these situations. The propagation of the fire and the effects of the fire on the plant process and the systems and the devices may be very hard to foresee and the circumstances may deteriorate the operators' physical and mental capacity. The problems of management are reflected in the difficulties experienced in the development of procedures and training for fire situations. The special features of the fire situations are problematic also in the assessment of human reliability. There are uncertainties in the modelling of the operator actions in probabilistic fire safety analysis (PSA). The methodology of human reliability becomes more uncertain when the analyses to be applied have been adopted from other areas of PSA. The way of applying the models concerning the internal events in the fire risk analyses is problematic because important information specific to fire situations may be lost. This is obvious for the effects that a fire may have on the control room information and on the automatic devices and systems. Due to these difficulties more knowledge is needed concerning the demands of the management of fire situations from the control room point of view. It is also important to utilise multidisciplinary co-operation for gaining this knowledge. There is a need for a method which makes it easier to understand the fire situations as the context of operators' judgement and decision-making. This kind of a method could contribute to supporting both the management of fire situations and the human reliability analyses concerning fires.
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