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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: Tue, 18-06-1991
ERF description: While at nominal power effort was in progress to repair the faulty pressure gauge of the main safety valve (MSV) control system of the primary circuit. In the course of this activity 2 MSVs out of 12 opened, and the steam was received by the accident isolation system as designed. Partial steam release to envorinment occurred through the clean air venting facility of the isolation system decay chamber. Permissible limits for activity release to environment were not exceedd. Once personnel activated the lines of forced closure, the above two valves closed. Repair of the faulty pressure gauge was performed without the established work program combined with the failure to take technical measures aimed at preventing unauthorized opening of MSVs.
BASIS FOR RATING: Initiator - coolant leak from the safety valve system. Criterion - degradation of defence-in-depth. Intital event - real, potential. Safety function availability: full, which corresponds to level 1/2 (A-2R). The event cause reveals deficiencies in the safety culture. Therefore the higher level out of the above two has been chosen.
DIFFICULTIES IN RATING:
ERF rating date: 01-01-1991
ERF contact person: Mr. V.I. Andreev
ERF address: Kitaisky Proezd 7, 103074 Moscow, Lithuania
ERF affiliation: Min. of Nuclear Power and Industry, of the USSR, Dept. of Principle, Accident Dispatch

This map shows a selection of reports from nuclear and radiological incidents stored in the IAEA NEWS-database.
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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