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Category:REPORTABLE OCCURRENCE REPORT (SEE ALSO AO LER)
MONTHYEARML20094E3301992-01-23023 January 1992 Ro:On 920109,determined That One of Two Level Safety Sys Was Malfunctioning Due to Failure of LM339 Comparator Chip.Chip Replaced & Monitoring Circuit Tested Satisfactorily on 920110 ML20236A8061989-03-0707 March 1989 Ro:On 890224,exhaust Fan Not Operating When Reactor Critical at 10W.Caused by Switch Snagged by Belt Loop as Individual Left Control Room.Reactor Scrammed & Fan Switch Returned to on Position ML20209F2761986-09-0808 September 1986 Ro:On 860903,during Std Shutdown of Reactor,Automatic Scram That Normally Occurs When Count Rate of Startup Channel Below 2 Cps Failed to Occur.Caused by Shorting of Input Signal.Startup Channel Repaired ML20076K8271983-08-24024 August 1983 Ro:During Reactor Operator Training Session,Air Monitor Near Bldg Exhaust Fan Briefly Did Not Monitor Reactor Room Effluent.Monitor Used in Sniffer Mode for Evaluating 150 Ar-41 Production.Monitor Will Be Run Normally in Future 1992-01-23
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML20212E7211999-06-30030 June 1999 Ohio State Univ Research Reactor Annual Rept for FY98/99. with ML20153E0961998-09-30030 September 1998 Oh State Univ Research Reactor Annual Rept for Fy 97/98. with ML20211B1661997-06-30030 June 1997 Oh State Univ Research Reactor Annual Rept for FY96/97 ML20136D6921997-03-0606 March 1997 Safety Evaluation Supporting Amend 17 to License R-75 ML20129D9601996-06-30030 June 1996 Oh State Univ Research Reactor Annual Rept for FY95/96 ML20092M8301995-06-30030 June 1995 Oh State University Research Reactor Annual Rept for FY94/95 ML20086A3611995-05-10010 May 1995 Trtr Peer Review for Oh State Univ Nuclear Reactor Lab, for 950214-15 ML20073G4251994-06-30030 June 1994 Oh State Univ Research Reactor Annual Rept for FY93/94. W/ ML20056F7721993-08-23023 August 1993 Safety Evaluation Supporting Amend 14 to License R-75 ML20118A7251992-06-30030 June 1992 Annual Rept for Ohio State Univ Research Reactor for 910701 Through 920630 ML20094E3301992-01-23023 January 1992 Ro:On 920109,determined That One of Two Level Safety Sys Was Malfunctioning Due to Failure of LM339 Comparator Chip.Chip Replaced & Monitoring Circuit Tested Satisfactorily on 920110 ML20083D8841991-09-26026 September 1991 Annual Rept for Ohio State Univ Research Reactor,Jul 1990 to June 1991 ML20062F0771990-11-14014 November 1990 Safety Evaluation Supporting Amend 13 to License R-75 ML20065K7541990-11-0101 November 1990 Rev 5 to Adminstriative Procedure AP-09, Reactor Operator/ Senior Reactor Operator Requalification ML20059N1751990-06-30030 June 1990 Annual Rept for License R-75 for Jul 1989 - June 1990 ML20247J9691989-03-0707 March 1989 QA Program for Ohio State Univ Nuclear Reactor Lab ML20236A8061989-03-0707 March 1989 Ro:On 890224,exhaust Fan Not Operating When Reactor Critical at 10W.Caused by Switch Snagged by Belt Loop as Individual Left Control Room.Reactor Scrammed & Fan Switch Returned to on Position ML20155A7251988-09-27027 September 1988 Safety Evaluation Supporting Order Converting License R-75 from High to Low Enriched U ML20215F9861986-12-16016 December 1986 Rev 3 to Administrative Procedure AP-07, Review of Procedures ML20215F9731986-12-15015 December 1986 Rev 3 to Administrative Procedure AP-09, Reactor Operator/ Senior Reactor Operator Requalification ML20211G9641986-10-27027 October 1986 Rev 2 to Administrative Procedure AP-09, Reactor Operator/ Senior Reactor Operator Requalification ML20209F2761986-09-0808 September 1986 Ro:On 860903,during Std Shutdown of Reactor,Automatic Scram That Normally Occurs When Count Rate of Startup Channel Below 2 Cps Failed to Occur.Caused by Shorting of Input Signal.Startup Channel Repaired ML20206M4091986-06-16016 June 1986 Safety Evaluation Supporting Amend 11 to License R-75 ML20076K8271983-08-24024 August 1983 Ro:During Reactor Operator Training Session,Air Monitor Near Bldg Exhaust Fan Briefly Did Not Monitor Reactor Room Effluent.Monitor Used in Sniffer Mode for Evaluating 150 Ar-41 Production.Monitor Will Be Run Normally in Future 1999-06-30
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T- 11 E Engineering Experiment Station 142 hitched llall
-* 2070 Neil A venue C 'umbus, Oli 43210-1275 4 ~ W- m phoac 614 292-4903
-4 FAX # 614-292 9021
- , .L_J UNIVIRSilY lZ3l'1~L Document Control Desk U.S. Neclear Regulatory Commission Washington D.C. 20555
Subject:
Reportable Occurrence at the Ohio State University Hestarch Reactor, License R-75, Docket No. 50-150 Whlie operating the OSURR on January 9, 1992 it was determined that one of the two level safety systems was malfunctioning. According to Technical Specification 6.5.2 (3) this is a reportable occurrence. Details of the event and responses as required by G.2.5 are described below.
At 1239 hours0.0143 days <br />0.344 hours <br />0.00205 weeks <br />4.714395e-4 months <br />, after about 43 minutes of operatlon, a Senior Reactor Operator noticed that the high voltage supply to the detector for Level Safety D was turned off. The result was that that $ safety channel was not performing its intended function. In order to return the system to normal the high voltage was turned on.
Upon further examination it was determined that the system monitoring the high voltage supply should have indicated that power was off and have prevent ^d the operation due to low voltage. This monitoring system was checked and funct ioning properly January 7, 1992. Ilowever an LM339 comparator chip in this system failed before the January 9, 1992 operation. This chip was replaced and the monitoring circuit was tested as satisfactory on January 10, 1992. Although the probability of recurrence is deemer' to be extremely low, to reduce this_further a procedural change shall be made. As a part of the pre-start checkout,the detector's high voltage power supplies shall be checked foi proper operation.
As required by T.S. 6.5,2 the Director of the OSURR, Don W. Miller, was notified. This report shall be submittled to him and shall be reviewed by'the Reactcr Operations Committee at its next meeting. In addition, as required by T.S. G.G.2, a telephcne report was made to NRC Region III on January 10, 1992. The report was made by Richard Myser of The Ohio State University t o Jim McCarmick-Itarger of Region III .
If you have any questions on the content of this letter pleasa contact Mr Myser_at 614-292-6755.
Sincerely k6dWYf Robert F. Redmond, Director 9201230157 92012? 'O 7
PDP ADOCK 050 College of Engineering o
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