This paper presents Vattenfall's development work to apply risk-based incidcators for operating experience feedback at nuclear power plants. The aim is to utilise risk follow-up by PSA for classification of safety significance of events such as reactor shutdowns and unavailabilities in safety related systems. The risk-based indicators complement the presently reported safety indicators. Several PSA-indicators are defined representing (1) core damage risk of shutdown events, (2) momentaneous core damage frequency as well as (3) addition to baseline core damage risk during unavailabilities of safety related systems. In addition, indicators are defined at functional level corresponding to unavailability of the main safety functions. The result of risk follow-up is presented as a matrix of indicators with three posible sitgnificance grades: Green, Yellow, Red. "Green" means that event is not important to safety or operating year has been normal, "Yellow" means a little reisk increase and "Red" significant risk increase. Examples are illustrated.
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