The requisite characteristics for diagnosis procedures based on the empirical findings of the operatorsʹ behavior under emergency situations

In this study, to suggest requisite characteristics for diagnosis procedures, the SROsʹ (senior reactor operators) behaviors in conducting the diagnosis procedure under simulated conditions are observed and analyzed in order to identify factors that make the performance of it difficult. As the results, four important characteristics that may be helpful in constructing effective and useful diagnosis procedures are suggested. These are: (1) the use of connection symbols should be minimized, (2) when connection symbols are used, precise information about entry symbols should be provided to the operators, (3) the use of negative expressions should be avoided, and (4) the diagnosis procedure should be constructed through the integration of both the non-compensatory and the compensatory approach. Although these characteristics are deduced, not from well-designed experiments, but from empirical observations, it is highly expected that the operatorsʹ diagnostic burden could be significantly reduced, if the above characteristics are properly embodied in the diagnosis procedures.