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Information Notices - 1993

Document Number Title Revision Publish Date Reviewed Date
IN-93-101 Jet Pump Hold-Down Beam Failure -- 12/17/1993 --
IN-93-100 Reporting Requirements for Bankruptcy -- 12/22/1993 --
IN-93-99 Undervoltage Relay and Thermal Overload Setpoint Problems -- 12/21/1993 --
IN-93-98 Motor Brakes on Valve Actuator Motors -- 12/20/1993 --
IN-93-97 Failures of Yokes Installed on Walworth Gate and Globe Valves -- 12/17/1993 --
IN-93-96 Improper Reset Causes Emergency Diesel Generator Failures -- 12/14/1993 --
IN-93-95 Storm-Related Loss of Offsite Power Events Due to Salt Buildup on Switchyard Insulators -- 12/13/1993 --
IN-93-94 Unauthorized Forced Entry Into the Protected Area At Three Mile Island Unit 1 on February 7, 1993 -- 12/09/1993 --
IN-93-93 Inadequate Control of Reactor Coolant System Conditions During Shutdown -- 12/08/1993 --
IN-93-92 Plant Improvements to Mitigate Common Dependencies in Component Cooling Water Systems -- 12/07/1993 --
IN-93-91 Misadjustment Between General Electric 4.16-KV Circuit Breakers and Their Associated Cubicles -- 12/03/1993 --
IN-93-90 Unisolatable Reactor Coolant System Leak Following Repeated Applications of Leak Sealant -- 12/01/1993 --
IN-93-89 Potential Problems with BWR Level Instrumentation Backfill Modifications -- 11/26/1993 --
IN-93-88 Status of Motor-Operated Valve Performance Prediction Program by the Electric Power Research Institute -- 11/30/1993 --
IN-93-87 Fuse Problems with Westinghouse 7300 Printed Circuit Cards -- 11/04/1993 --
IN-93-86 Identification of Isotopes in the Production and Shipment of Byproduct Material at Non-Power Reactors -- 10/29/1993 --
IN-93-85 Problems with X-Relays in DB- and DHB-Type Circuit Breakers Manufactured by Westinghouse 1 01/20/1994 --
-- 10/20/1993 --
IN-93-84 Determination of Westinghouse Reactor Coolant Pump Seal Failure -- 10/20/1993 --
IN-93-83 Potential Loss of Spent Fuel Pool Cooling Following a Loss of Coolant Accident (LOCA) S1 08/24/1995 --
-- 10/07/1993 --
IN-93-82 Recent Fuel and Core Performance Problems in Operating Reactors -- 10/12/1993 --
IN-93-81 Implementation of Engineering Expertise on Shift -- 10/12/1993 --
IN-93-80 Implementation of the Revised 10 CFR Part 20 W 82 FR 18316
04/18/2017
--
-- 10/08/1993 --
IN-93-79 Core Shroud Cracking at Beltline Region Welds in Boiling-Water Reactors -- 09/30/1993 --
IN-93-78 Inoperable Safety Systems at a Non-Power Reactor -- 10/04/1993 --
IN-93-77 Human Errors That Result in Inadvertent Transfers of Special Nuclear Material at Fuel Cycle Facilities -- 10/04/1993 --
IN-93-76 Inadequate Control of Paint and Cleaners for Safety-Related Equipment -- 09/21/1993 --
IN-93-75 Spurious Tripping of Low-Voltage Power Circuit Breakers with GE RMS-9 Digital Trip Units -- 09/17/1993 --
IN-93-74 High Temperatures Reduce Limitorque AC Motor Operator Torque -- 09/16/1993 --
IN-93-73 Criminal Prosecution of Nuclear Suppliers for Wrongdoing -- 09/15/1993 --
IN-93-72 Observations From Recent Shutdown Risk and Outage Management Pilot Team Inspections -- 09/14/1993 --
IN-93-71 Fire At Chernobyl Unit 2 -- 09/13/1993 --
IN-93-70 Degradation of Boraflex Neutron Absorber Coupons -- 09/10/1993 --
IN-93-69 Radiographic Events At Operating Power Reactors -- 09/02/1993 --
IN-93-68 Failure of Pump Shaft Coupling Caused By Temper Embrittlement During Manufacture -- 09/01/1993 --
IN-93-67 Bursting of High Pressure Coolant Injection Steam Line Rupture Discs Injures Plant Personnel -- 08/16/1993 --
IN-93-66 Switchover to Hot-Leg Injection Following a Loss-Of-Coolant Accident in Pressurized Water Reactors -- 08/16/1993 --
IN-93-65 Reactor Trips Caused By Breaker Testing with Fault Protection Bypassed -- 08/13/1993 --
IN-93-64 Periodic Testing and Preventative Maintenance of Molded Case Circuit Breakers -- 08/12/1993 --
IN-93-63 Improper Use of Soluble Weld Purge Dam Material -- 08/11/1993 --
IN-93-62 Thermal Stratification of Water in BWR Reactor Vessels -- 08/10/1993 --
IN-93-61 Excessive Reactor Coolant Leakage Following a Seal Failure in a Reactor Coolant Pump or Reactor Recirculation Pump -- 08/09/1993 A 08/09/1993 B --
IN-93-60 Reporting Fuel Cycle and Materials Events to the NRC Operations Center S1 10/20/1994 --
-- 08/04/1993 --
IN-93-59 Unexpected Opening of Both Doors in an Airlock -- 07/26/1993 --
IN-93-58 Nonconservatism in Low-Temperature Overpressure Protection for Pressurized-Water Reactors -- 07/26/1993 --
IN-93-57 Software Problems Involving Digital Control Console Systems at Non-Nuclear Reactors -- 07/23/1993 --
IN-93-56 Weakness in Emergency Operating Procedures Found as Result of Steam Generator Tube Rupture -- 07/22/1993 --
IN-93-55 Potential Problem with Main Steamline Break Analysis for Main Steam Vaults/Tunnels -- 07/21/1993 --
IN-93-54 Motor-Operated Valve Actuator Thrust Variations Measured with a Torque Thrust Cell and a Strain Gage -- 07/20/1993 --
IN-93-53 Effect of Hurricane Andrew on Turkey Point Nuclear Generating Station and Lessons Learned S1 04/29/1994 --
-- 07/20/1993 --
IN-93-52 Draft NUREG-1477, "Voltage-Based Interim Plugging Criteria for Steam Generator Tubes" -- 07/14/1993 --
IN-93-51 Repetitive Overspeed Tripping of Turbine-Driven Auxiliary Feedwater Pumps -- 07/09/1993 --
IN-93-50 Extended Storage of Sealed Sources -- 07/08/1993 --
IN-93-49 Improper Integration of Software Into Operating Practices -- 07/08/1993 --
IN-93-48 Failure of Turbine-Driven Main Feedwater Pump To Trip Because of Contaminated Oil -- 07/06/1993 --
IN-93-47 Unrecognized Loss of Control Room Annunciators -- 06/18/1993 --
IN-93-46 Potential Problem with Westinghouse Rod Control System & Inadvertent Withdrawal of a Single Rod Control Cluster Assembly -- 06/10/1993 --
IN-93-45 Degradation of Shutdown Cooling System Performance -- 06/16/1993 --
IN-93-44 Operational Challenges During a Dual-Unit Transient -- 06/15/1993 --
IN-93-43 Use of Inappropriate Lubrication Oils in Safety-Related Applications -- 06/10/1993 --
IN-93-42 Failure of Anti-Rotation Keys in Motor-Operated Valves Manufactured by Velan -- 06/09/1993 --
IN-93-41 One Hour Fire Endurance Test Results for ... Kaowool, ... FS-195, and ... Interam E-50 Fire Fire Barrier Systems -- 05/28/1993 --
IN-93-40 Fire Endurance Test Results for Thermal Ceramics FP-60 Fire Barrier Material -- 05/26/1993 --
IN-93-39 Radiation Beams From Power Reactor Biological Shields -- 05/25/1993 --
IN-93-38 Inadequate Testing of Engineered Safety Features Actuation Systems -- 05/24/1993 --
IN-93-37 Eyebolts with Indeterminate Properties Installed in Limitorque Valve Operator Housing Covers -- 05/19/1993 --
IN-93-36 Notifications, Reports, and Records of Misadministrations -- 05/07/1993 --
IN-93-35 Insights From Common-Cause Failure Events -- 05/12/1993 --
IN-93-34 Potential for Loss of Emergency Cooling Function Due to a Combination of Operational and Post-LOCA Debris in Containment S1 05/06/1993 --
-- 04/26/1993 --
IN-93-33 Potential Deficiency of Certain Class 1E Instrumentation and Control Cables -- 04/28/1993 --
IN-93-32 Nonconservative Inputs for Boron Dilution Event Analysis -- 04/21/1993 --
IN-93-31 Training of Nurses Responsible for the Care of Patients with Brachytherapy Implants -- 04/13/1993 --
IN-93-30 NRC Requirements for Evaluation of Wipe Test Results; Calibration of Count Rate Survey Instruments -- 04/12/1993 --
IN-93-29 Problems with the Use of Unshielded Test Leads in Reactor Protection System Circuitry -- 04/12/1993 --
IN-93-28 Failure to Consider Loss of DC Bus in the Emergency Core Cooling System Evaluation May Lead to Nonconservative Analysis -- 04/09/1993 --
IN-93-27 Level Instrumentation Inaccuracies Observed During Normal Plant Depressurization -- 04/08/1993 --
IN-93-26 Grease Solidification Causes Molded-Case Circuit Breaker Failure to Close S1 01/31/1994 --
-- 04/07/1993 --
IN-93-25 Electrical Penetration Assembly Degradation -- 04/01/1993 --
IN-93-24 Distribution of Revision 7 of NUREG-1021, "Operator Licensing Examiner Standards" -- 03/31/1993 --
IN-93-23 Weschler Instruments Model 252 Switchboard Meters -- 03/31/1993 --
IN-93-22 Tripping of Klockner-Moeller Molded-Case Circuit Breakers Due to Support Lever Failure -- 03/26/1993 --
IN-93-21 Summary of ... Observations Compiled During Engineering Audits or Inspections of Licensee Erosion/Corrosion Programs -- 03/25/1993 --
IN-93-20 Thermal Fatigue Cracking of Feedwater Piping to Steam Generators -- 03/24/1993 --
IN-93-19 Slab Hopper Bulging -- 03/17/1993 --
IN-93-18 Portable Moisture-Density Gauge User Responsibilities During Field Operations -- 03/10/1993 --
IN-93-17 Safety Systems Response to Loss of Coolant and Loss of Offsite Power 1 03/25/1994 --
-- 03/08/1993 --
IN-93-16 Failures of Nut-Locking Devices in Check Valves -- 02/19/1993 --
IN-93-15 Failure to Verify the Continuity of Shunt Trip Attachment Contacts in Manual Safety Injection and Reactor Trip Switches -- 02/18/1993 --
IN-93-14 Clarification of 10 CFR 40.22, Small Quantities of Source Material -- 02/18/1993 --
IN-93-13 Undetected Modification of Flow Characteristics in the High Pressure Safety Injection System -- 02/16/1993 --
IN-93-12 Off-Gassing in Auxiliary Feedwater System Raw Water Sources -- 02/11/1993 --
IN-93-11 Single Failure Vulnerability of Engineered Safety Features Actuation Systems -- 02/04/1993 --
IN-93-10 Dose Calibrator Quality Control -- 02/02/1993 --
IN-93-09 Failure of Undervoltage Trip Attachment on Westinghouse Model DB-50 Reactor Trip Breaker -- 02/02/1993 --
IN-93-08 Failure of Residual Heat Removal Pump Bearings Due to High Thrust Loading -- 02/01/1993 --
IN-93-07 Classification of Transportation Emergencies -- 02/01/1993 --
IN-93-06 Potential Bypass Leakage Paths Around Filters Installed in Ventilation Systems -- 01/22/1993 --
IN-93-05 Locking of Radiography Exposure Devices -- 01/14/1993 --
IN-93-04 Investigation and Reporting of Misadministrations by the Radiation Safety Officer -- 01/07/1993 --
IN-93-03 Recent Revisions to 10 CFR Part 20 and Change of Implementation Date to January 1, 1994 W 82 FR 18316
04/18/2017
--
-- 01/05/1993 --
IN-93-02 Malfunction of a Pressurizer Code Safety Valve -- 01/04/1993 --
IN-93-01 Accuracy of Motor-Operated Valve Diagnostic Equipment Manufactured by Liberty Technologies -- 01/04/1993 --

Page Last Reviewed/Updated Monday, March 3, 2025