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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: Sat, 07-07-2001
ERF description: During recommissioning of the Fueling Machine (F/M) on completion of an extensive fuel route outage a "link" was identified that defeated both channels of dP/dt protection which act to restrict depressurisation of the F/M in the event of a breach of the cooling system. There are three trip parameters used to protect against a breach, but for a range of smaller breach sizes dP/dt protection provides protection against levitation of an irradiated fuel stringer being moved during refuelling, and consequently provides important protection against potentially dropping the fuel, damaging fuel cladding and releasing activity. For a range of smaller breach sizes only the dP/dt protection provides protection against levitation. The station reported the event promptly and appropriately.
Initial information in the week following discovery of links was that they had been applied outside the Station's formal safety management systems at an undefined date and consequently may have been in place when the fuelling machine was actually being used to move irradiated fuel. The event was rated under INES at "2". Subsequently a panel of investigation was convened and its investigations identified that the links had been applied under a maintenance procedure, that is in accordance with a formal safety management system. The maintenance staff involved with the work had not initially recalled the use of the procedure. Additionally the procedure had required the links to be removed but this step had apparently been overlooked although it had been identified as "complete" within the procedure. Although there are still issues associated with the adequacy of the maintenance procedure and its application that still support the original event categorisation, the new information justifies a re-evaluation of the INES rating.
This report details the INES review and is the vehicle for re-notification of a new INES rating of "1".

ERF rating date: 01-06-2001
ERF contact person: D.J.Western, Director HSED
ERF address: BRITISH ENERGY, Barnett Way, Barnwood, Gloucester, GL4 3RS

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