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On August 16, 2001, Instrument Maintenance … On August 16, 2001, Instrument Maintenance Department (IMD) technicians began maintenance activities on the Unit 2 containment area radiation monitor 2AR11J. During the activity, an IMD technician improperly landed an electrical lead and caused the failure of several printed circuit boards. An emergent repair ensued which involved the improper re-installation of an output relay. This relay provides a containment ventilation isolation signal to the solid state protection system (SSPS). The faulty installation caused a permanent containment ventilation signal to be present. A containment ventilation isolation signal was generated and subsequently reset in the control room with the belief the signal was spurious due to the maintenance restoration activity. The reset activity blocked the signal from reactivation, though it was still present. The post maintenance test to demonstrate operability did not check the function of this relay and consequently, the monitor was restored to operable status with a faulty relay. The error was discovered 15 days later during the execution of an SSPS surveillance. The root causes were determined to be an improper installation of the relay by the IMD technician and a knowledge deficiency by the IMD and operations supervision in determining the post maintenance testing requirements. Corrective actions include counseling the IMD technicians involved and training the IMD and operations personnel to improve system knowledge. Due to redundant actuation trains and diverse isolation signals, there were no safety consequences as a result of this event. This event is reportable to the NRC in accordance with 10CFR 50.73 (a)(2)(i)(b).</br></br>(p:011ers 455-2001-004-00.doc) b)(i)(b).
(p:011ers 455-2001-004-00.doc) b +
On August 16, 2001, Instrument Maintenance … On August 16, 2001, Instrument Maintenance Department (IMD) technicians began maintenance activities on the Unit 2 containment area radiation monitor 2AR11J. During the activity, an IMD technician improperly landed an electrical lead and caused the failure of several printed circuit boards. An emergent repair ensued which involved the improper re-installation of an output relay. This relay provides a containment ventilation isolation signal to the solid state protection system (SSPS). The faulty installation caused a permanent containment ventilation signal to be present. A containment ventilation isolation signal was generated and subsequently reset in the control room with the belief the signal was spurious due to the maintenance restoration activity. The reset activity blocked the signal from reactivation, though it was still present. The post maintenance test to demonstrate operability did not check the function of this relay and consequently, the monitor was restored to operable status with a faulty relay. The error was discovered 15 days later during the execution of an SSPS surveillance. The root causes were determined to be an improper installation of the relay by the IMD technician and a knowledge deficiency by the IMD and operations supervision in determining the post maintenance testing requirements. Corrective actions include counseling the IMD technicians involved and training the IMD and operations personnel to improve system knowledge. Due to redundant actuation trains and diverse isolation signals, there were no safety consequences as a result of this event. This event is reportable to the NRC in accordance with 10CFR 50.73 (a)(2)(i)(b).</br></br>(p:011ers 455-2001-004-00.doc) b)(i)(b).
(p:011ers 455-2001-004-00.doc) b +
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Technical Specification Non-Compliance Caused by Improper Component Installation and Post Maintenance Test on an Area Radiation Monitor that Generates an Automatic Containment Ventilation Isolation Signal +
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