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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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The Ohio State University 0v Engineering Experiment Station l 142 Hitchcock Hall 2070 Neil Avenue Columbus, Ohio 43210 Phone 614 422-2411 September 8, 1986 Mr. John Dosa Standardization and Special Projects Branch Division of Licensing U.S. Nuclear Regulatory Commission Washington DC 20555 RE: Report of Safety System Failure, License R-75 Docket 50-150.
The Ohio State University Research Reactor
Dear Mr. Dosa:
This letter is to report an incident as required by the R-75 license (#3D(1) Reports). Please be advised that Mr. Dominic Tondi of your office and Mr. Ken Ridgeway of the Regional Office (III) were also notified by telephone on September 4, 1986.
On September 3,1986 during a standard shutdown of the Reactor the count rate on the Startup Channel was allowed to go below 2 cps. This was done for training to demonstrate the automatic scram that normally occurs at this point. On this occasion the scram did not occur which indicated a failure that could have prevented this safety system from functioning properly. This safety system is designed to prevent a startup if the indicated count rate is less than 2 cps.
On July 1, 1986 this scram function had been checked as is required by Technical Specification 9.3 and Procedure IM-01 " Routine Checks of Control and Scram Instrumentation". At this time it did function properly. Since that time the reactor had been started up a total of 15 times before the above failure was noted. A check of our operations logbook and prestart checkout logbook indicated that the startup channel appeared to be working properly with normal count rates above 2 cps.
Once the malfunction was noted, repairs to the system were begun.
Within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> the startup channel was repaired and tested. The cause was determined to be shorting of the input signal to ground when the slow scram console was inserted, probably due to a weak or worn connecting pin. To repair the system the connection was jumpered to a spare amplifier in the slow scram panel. The startup channel was then tested satisfactorily according to scram test requirements.
8609120106 860908 fp PDR ADOCK 05000150 S PDR College of Engineering
Mr. John Dosa September 8, 1986
- Page Two If you have any questions on this matter please contact Mr. Richard Myser or Mr. Joseph Talnagi at 614/422-6755.
Sincerely, Robert F. Redmond Director RFR/sh c: D. W. Miller, Director, NRL J. G. Kepler, U.S. NRC Region III 5
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