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Event Report Forms (ERFs) are filed to the IAEA. Sometimes there are multiple event reports, updating the rating, the event description. Here you only see the latest event report

ERF send date: Thu, 19-01-1995
ERF description: Wolsong unit 1 was operated at rated power. At 05:11, October 20, 1994 one of the liquid relief valves in the reactor coolant system was opened due to trouble with valve operating mechanism (diaphragm damage). This caused decrease of pressurizer level and resulted in reactor trip by "pressurizer level low" signal. At 06:56 an overpressure protection valve of Degasser-condenser was opened. Reactor coolant system was fully cooled down at 08:10 the same day.
About 6.5 tons of heavy water leaked into heavy water recovery system. No radiation exposure of workers happened.
This event was evaluated as level 1 tentatively. But further investigation revealed that procedures were inadequate to overcome this event.
So the Evaluation Committee of Severity on Incident and Failure determined to apply additional factor. The final rating of this event is 2.
Justification: As full safety functions were available the event is rated at level "0" as per user's manual Part III, Table II, A2 and Part III-5.
ERF rating date: 06-01-1995
ERF contact person: Y.-H. KIM
ERF address: 1 JOONGANG-DONG, GWACHEON CITY, South Korea
ERF affiliation: MOST

This map shows a selection of reports from nuclear and radiological incidents stored in the IAEA NEWS-database.
Locations are estimates. Contact us if a location is wrong.
The map shows a maximum of 100 incidents. If hundred incidents or more are within the map, the yellow perimeter indicates from where events are excluded. Drag or zoom the map to explore different areas.

Power Reactor Research Reactor Radwaste Facility Enrichment Facility Radiation Source Irradiation/Accelerator Facility Transportation

Fuel Fabrication Fuel Reprocessing Research Facility Mining/Milling Radioisotope Processing/Handling Facility Other