A potential sequence of events affecting safety, beginning with a grid disturbance, was identified in the safety analyses of unit 3 at Finland’s Olkiluoto NPP. Immediate corrective actions were taken to ensure the continuation of electricity production without interruption, Finnish power utility Teollisuuden Voima Oyj (TVO) said.
A network disturbance could have led to the inoperability of certain equipment related to reactor cooling. Immediate corrective measures were implemented, and electricity production at the OL3 plant unit continued without interruption.
TVO submitted a preliminary operational event report to the Radiation and Nuclear Safety Authority (STUK – Säteilyturvakeskus). TVO has initially assessed the severity of the event as level 1 on the International Nuclear & Radiological Event Scale (INES). STUK will confirm the final INES rating in connection with its review of the special report.
