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Category:NRC Information Notice
MONTHYEARInformation Notice 2007-05, Vertical Deep Draft Pump Shaft and Coupling Failures2007-02-0909 February 2007 Vertical Deep Draft Pump Shaft and Coupling Failures Information Notice 2002-34, Failure of Safety-Related Circuit Breaker External Auxiliary Switches at Columbia Generating Station2002-11-25025 November 2002 Failure of Safety-Related Circuit Breaker External Auxiliary Switches at Columbia Generating Station Information Notice 1999-28, Recall of Star Brand Fire Protection Sprinkler Heads1999-09-30030 September 1999 Recall of Star Brand Fire Protection Sprinkler Heads Information Notice 1999-27, Malfunction of Source Retraction Mechanism in Cobalt-60 Teletherapy Treatment Units1999-09-0202 September 1999 Malfunction of Source Retraction Mechanism in Cobalt-60 Teletherapy Treatment Units Information Notice 1999-26, Safety and Economic Consequences of Misleading Marketing Information1999-08-24024 August 1999 Safety and Economic Consequences of Misleading Marketing Information Information Notice 1999-25, Year 2000 Contingency Planning Activities1999-08-10010 August 1999 Year 2000 Contingency Planning Activities Information Notice 1999-24, Broad-Scope Licensees' Responsibilities for Reviewing and Approving Unregistered Sealed Sources and Devices1999-07-12012 July 1999 Broad-Scope Licensees' Responsibilities for Reviewing and Approving Unregistered Sealed Sources and Devices Information Notice 1999-23, Safety Concerns Related to Repeated Control Unit Failures of the Nucletron Classic Model High-Dose-Rate Remote Afterloading Brachytherapy Devices1999-07-0606 July 1999 Safety Concerns Related to Repeated Control Unit Failures of the Nucletron Classic Model High-Dose-Rate Remote Afterloading Brachytherapy Devices Information Notice 1999-22, 10CFR 34.43(a)(1); Effective Date for Radiographer Certification and Plans for Enforcement Discretion1999-06-25025 June 1999 10CFR 34.43(a)(1); Effective Date for Radiographer Certification and Plans for Enforcement Discretion Information Notice 1999-21, Recent Plant Events Caused by Human Performance Errors1999-06-25025 June 1999 Recent Plant Events Caused by Human Performance Errors Information Notice 1999-20, Contingency Planning for the Year 2000 Computer Problem1999-06-25025 June 1999 Contingency Planning for the Year 2000 Computer Problem Information Notice 1999-19, Rupture of the Shell Side of a Feedwater Heater at the Point Beach Nuclear Plant1999-06-23023 June 1999 Rupture of the Shell Side of a Feedwater Heater at the Point Beach Nuclear Plant Information Notice 1999-18, Update on Nrc'S Year 2000 Activities for Material Licensees and Fuel Cycle Licensees and Certificate Holders1999-06-14014 June 1999 Update on Nrc'S Year 2000 Activities for Material Licensees and Fuel Cycle Licensees and Certificate Holders Information Notice 1999-17, Problems Associated with Post-Fire Safe-Shutdown Circuit Analyses1999-06-0303 June 1999 Problems Associated with Post-Fire Safe-Shutdown Circuit Analyses Information Notice 1999-16, Federal Bureau of Investigation'S Nuclear Site Security Program1999-05-28028 May 1999 Federal Bureau of Investigation'S Nuclear Site Security Program Information Notice 1999-15, Misapplication for 10CFR Part 71 Transportation Shipping Cask Licensing Basis to 10CFR Part 50 Design Basis1999-05-27027 May 1999 Misapplication for 10CFR Part 71 Transportation Shipping Cask Licensing Basis to 10CFR Part 50 Design Basis Information Notice 1999-14, Unanticipated Reactor Water Draindown at Quad Cities Unit 2, Arkansas Nuclear One Unit 2, & FitzPatrick1999-05-0505 May 1999 Unanticipated Reactor Water Draindown at Quad Cities Unit 2, Arkansas Nuclear One Unit 2, & FitzPatrick Information Notice 1999-13, Insights from NRC Inspections of Low-and Medium-Voltage Circuit Breaker Maintenance Programs1999-04-29029 April 1999 Insights from NRC Inspections of Low-and Medium-Voltage Circuit Breaker Maintenance Programs Information Notice 1999-12, Year 2000 Computer Systems Readiness Audits1999-04-28028 April 1999 Year 2000 Computer Systems Readiness Audits Information Notice 1999-11, Incidents Involving the Use of Radioactive Iodine-1311999-04-16016 April 1999 Incidents Involving the Use of Radioactive Iodine-131 Information Notice 1999-08, Urine Specimen Adulteration1999-03-26026 March 1999 Urine Specimen Adulteration Information Notice 1999-09, Problems Encountered When Manually Editing Treatment Data on the Nucletron Microselectron-HDR (New) Model 105-9991999-03-24024 March 1999 Problems Encountered When Manually Editing Treatment Data on the Nucletron Microselectron-HDR (New) Model 105-999 Information Notice 1999-07, Failed Fire Protection Deluge Valves & Potential Testing Deficiencies in Preaction Sprinkler Systems1999-03-22022 March 1999 Failed Fire Protection Deluge Valves & Potential Testing Deficiencies in Preaction Sprinkler Systems Information Notice 1999-06, 1998 Enforcement Sanctions as a Result of Deliberate Violations of NRC Employee Protection Requirements1999-03-19019 March 1999 1998 Enforcement Sanctions as a Result of Deliberate Violations of NRC Employee Protection Requirements Information Notice 1999-06, 1998 Enforcement Sanctions As a Result of Deliberate Violations of NRC Employee Protection Requirements1999-03-19019 March 1999 1998 Enforcement Sanctions As a Result of Deliberate Violations of NRC Employee Protection Requirements Information Notice 1999-05, Inadvertent Discharge of Carbon Dioxide Fire Protection System and Gas Migration1999-03-0808 March 1999 Inadvertent Discharge of Carbon Dioxide Fire Protection System and Gas Migration Information Notice 1999-04, Unplanned Radiation Exposures to Radiographers, Resulting from Failures to Follow Proper Radiation Safety Procedures1999-03-0101 March 1999 Unplanned Radiation Exposures to Radiographers, Resulting from Failures to Follow Proper Radiation Safety Procedures Information Notice 1999-03, Exothermic Reactors Involving Dried Uranium Oxide Powder (Yellowcake)1999-01-29029 January 1999 Exothermic Reactors Involving Dried Uranium Oxide Powder (Yellowcake) Information Notice 1999-02, Guidance to Users on the Implementation of a New Single-Source Dose-Calculation Formalism and Revised Air-Kerma Strength Standard for Iodine-125 Sealed Sources1999-01-21021 January 1999 Guidance to Users on the Implementation of a New Single-Source Dose-Calculation Formalism and Revised Air-Kerma Strength Standard for Iodine-125 Sealed Sources Information Notice 1999-01, Deterioration of High-Efficiency Particulate Air Filters in a Pressurized Water Reactor Containment Fan Cooler Unit1999-01-20020 January 1999 Deterioration of High-Efficiency Particulate Air Filters in a Pressurized Water Reactor Containment Fan Cooler Unit Information Notice 1998-45, Cavitation Erosion of Letdown Line Orifices Resulting in Fatigue Cracking of Pipe Welds1998-12-15015 December 1998 Cavitation Erosion of Letdown Line Orifices Resulting in Fatigue Cracking of Pipe Welds Information Notice 1998-44, Ten-Year Inservice Inspection (ISI) Program Update for Licensees That Intend to Implement Risk-Informed ISI of Piping1998-12-10010 December 1998 Ten-Year Inservice Inspection (ISI) Program Update for Licensees That Intend to Implement Risk-Informed ISI of Piping Information Notice 1998-43, Leaks in Emergency Diesel Generator Lubricating Oil & Jacket Cooling Water Piping1998-12-0404 December 1998 Leaks in Emergency Diesel Generator Lubricating Oil & Jacket Cooling Water Piping Information Notice 1998-42, Implementation of 10 CFR 55.55a(g) Inservice Inspection Requirements1998-12-0101 December 1998 Implementation of 10 CFR 55.55a(g) Inservice Inspection Requirements Information Notice 1998-41, Spurious Shutdown of Emergency Diesel Generators from Design Oversight1998-11-20020 November 1998 Spurious Shutdown of Emergency Diesel Generators from Design Oversight Information Notice 1998-41, Spurious Shutdown of Emergency Diesel Generators From Design Oversight1998-11-20020 November 1998 Spurious Shutdown of Emergency Diesel Generators From Design Oversight Information Notice 1998-39, Summary of Fitness-for-Duty Program Performance Reports for Calendar Years 1996 and 19971998-10-30030 October 1998 Summary of Fitness-for-Duty Program Performance Reports for Calendar Years 1996 and 1997 Information Notice 1998-40, Design Deficiencies Can Lead to Reduced ECCS Pump Net Positive Suction Head During Design-Basis Accidents1998-10-26026 October 1998 Design Deficiencies Can Lead to Reduced ECCS Pump Net Positive Suction Head During Design-Basis Accidents Information Notice 1990-66, Incomplete Draining and Drying of Shipping Casks1998-10-25025 October 1998 Incomplete Draining and Drying of Shipping Casks Information Notice 1998-38, Metal-Clad Circuit Breaker Maintenance Issues Identified by NRC Inspections1998-10-15015 October 1998 Metal-Clad Circuit Breaker Maintenance Issues Identified by NRC Inspections Information Notice 1998-37, Eligibility of Operator License Applicants1998-10-0101 October 1998 Eligibility of Operator License Applicants Information Notice 1998-36, Inadequate or Poorly Controlled, Non-Safety-Related Maintenance Activities Unnecessarily Challenged Safety Systems1998-09-18018 September 1998 Inadequate or Poorly Controlled, Non-Safety-Related Maintenance Activities Unnecessarily Challenged Safety Systems Information Notice 1998-33, NRC Regulations Prohibit Agreements That Restrict or Discourage an Employee from Participating in Protected Activities1998-08-28028 August 1998 NRC Regulations Prohibit Agreements That Restrict or Discourage an Employee from Participating in Protected Activities Information Notice 1998-34, Configuration Control Errors1998-08-28028 August 1998 Configuration Control Errors Information Notice 1998-31, Fire Protection System Design Deficiencies and Common-Mode Flooding of Emergency Core Cooling System Rooms at Washington Nuclear Project Unit 21998-08-18018 August 1998 Fire Protection System Design Deficiencies and Common-Mode Flooding of Emergency Core Cooling System Rooms at Washington Nuclear Project Unit 2 Information Notice 1998-30, Effect of Year 2000 Computer Problem on NRC Licensees and Certificate Holders1998-08-12012 August 1998 Effect of Year 2000 Computer Problem on NRC Licensees and Certificate Holders Information Notice 1998-29, Predicted Increase in Fuel Rod Cladding Oxidation1998-08-0303 August 1998 Predicted Increase in Fuel Rod Cladding Oxidation Information Notice 1998-28, Development of Systematic Sample Plan for Operator Licensing Examinations1998-07-31031 July 1998 Development of Systematic Sample Plan for Operator Licensing Examinations Information Notice 1998-26, Settlement Monitoring and Inspection of Plant Structures Affected by Degradation of Porous Concrete Subfoundations1998-07-24024 July 1998 Settlement Monitoring and Inspection of Plant Structures Affected by Degradation of Porous Concrete Subfoundations Information Notice 1998-27, Steam Generator Tube End Cracking1998-07-24024 July 1998 Steam Generator Tube End Cracking 2007-02-09
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UNITED STATESNUCLEAR REGULATORY COMMISSIONOFFICE OF NUCLEAR REACTOR REGULATIONWASHINGTON, D.C. 20555-0001February 9, 2007NRC INFORMATION NOTICE 2007-05: VERTICAL DEEP DRAFT PUMP SHAFT AND COUPLING FAILURES
ADDRESSEES
All holders of operating licensees for nuclear power reactors, except those who havepermanently ceased operations and have certified that fuel has been permanently removed
from the reactor vessel.
PURPOSE
The Nuclear Regulatory Commission (NRC) is issuing this Information Notice (IN) to alertlicensees to vertical deep draft pump shaft and coupling failures from intergranular stress
corrosion cracking (IGSCC). It is expected that recipients will review the information for
applicability to their facilities and consider actions, as appropriate, to avoid similar problems.
However, suggestions contained in this IN are not NRC requirements; therefore, no specific
action or written response is required.
DESCRIPTION OF CIRCUMSTANCES
Service Water Pump Shaft Failures at Columbia Generating StationAt Columbia Generating Station on June 14, 2005, following a start of the Service Water Pump1A (SW-P-1A), control room operators noted that service water (SW) flow to the Division 1 residual heat removal heat exchanger was out of specification. Operators also noted the pump
discharge head and pump motor current were lower than normal and declared the SW-P-1A
inoperable. A subsequent surveillance test on SW-P-1A determined that pump performance
had degraded and was operating at the intersection of the alert and action ranges of its
performance curve. Energy Northwest, the licensee, proceeded to replace SW-P-1A with an
available spare pump.During disassembly of SW-P-1A, Energy Northwest determined that IGSCC failed the pumpshaft end flanges on two of the shaft sections allowing the shaft sections to drop. This
condition caused the pump impeller to contact the pump suction casing, which resulted in
substantial wear of the pump impellers and degraded pump performance. The shaft drive keys
remained captured between the shaft keyways and coupling sleeves such that the shaft
segments and impeller continued to rotate. Energy Northwest conducted a metallurgical
examination of the damaged pump shaft and also identified axial cracking on the impeller pump
shaft segment and two diagonal cracks on the top column shaft. The metallurgical examination determined that the shaft material, TP410 martensitic stainlesssteel, was susceptible to tempering embrittlement (shaft material was tempered at 970 degrees
Fahrenheit, which was conducive to tempering embrittlement). Tempering embrittlement
reduced the corrosion resistance of the shaft material, thereby, increasing the material's
susceptibility to IGSCC. Energy Northwest determined that SW-P-1B was also susceptible to
the same failure mechanism as identified in SW-P-1A. However, it had not exhibited
performance degradation based on past surveillance test results. Interim corrective actions included additional monitoring of SW-P-1B to verify pumpperformance until a replacement pump could be procured and installed. A subsequent
inspection of the as-found condition of SW-P-1B determined that the pump shaft had degraded
in a manner similar to SW-P-1A, due to IGSCC, and that the pump impeller had degraded due
to wearing on the suction casing. A detailed evaluation of SW-P-1A historical computer data determined that although pumpperformance had met surveillance test acceptance criteria, pump performance had slowly
degraded from as early as August 2000 and as late as December 2001. Similarly, a detailed
evaluation of SW-P-1B historical computer data revealed that SW-P-1B had slowly degraded
since August 2003.Safety Function of SW-P-1A and SW-P-1B and Design InformationThe standby SW system and ultimate heat sink function is to supply cooling water toremove heat from all nuclear plant equipment that are essential for safe and orderly shutdown
of the reactor, to maintain it in a safe condition, and to remove decay heat from the reactor
during shutdown conditions. During all normal operating conditions, including normal shutdown
as well as emergency conditions, waste heat from the reactor auxiliary systems is transferred to
the ultimate heat sink via the standby SW system.SW-P-1A and SW-P-1B are deep draft vertical pumps manufactured by Byron Jackson, Model28KXH3, and were originally designed to provide a minimum of 10,500 gpm rated flow at 500 ft
of discharge head. Both pumps were installed in 1979 and, prior to the failure of SW-P-1A, had
not been replaced, refurbished, removed, or opened for inspection since initial installation. Both
pumps are exposed to the same environmental and physical conditions.The standby SW pump design consists of five sections of shaft with four sets of shaftcoupling components. Each set of shaft coupling components consists of two drive keys and a
pair of split rings that are held by a shaft coupling (sleeve) which is located by two gib keys. At
the point where two shaft sections join, the split rings are installed over mating shaft shoulder
flanges. The shaft shoulder flanges were the failed components which allowed the pump shaft
to drop, causing the pump impeller to rest on the casing bowl, thereby, resulting in milling and
wear of the impeller into the bowl during operation.Additional Service Water Pump Shaft and Shaft Coupling FailuresNRC review of Operating Experience records identified at least 23 essential SW pump shaftand coupling failures since 1983 involving more than six different pump manufacturers. Many
of these failures involved IGSCC as a primary cause. Other causes of shaft and couplingfailures included: misalignment, imbalance, installation errors, and deferred maintenance. Two
incidents since 2001, involving IGSCC are: (1) Perry experienced SW pump shaft coupling failures due to IGSCC in September 2003 andMay 2004. These failures are described in NRC Inspection Reports 05000440/200401, dated
July 2, 2004, and 050000440/2004008, dated August 4, 2004, (Agencywide Documents Access
and Management System (ADAMS) Accession Nos. ML041900080 and ML042250254).
(2) VC Summer experienced SW pump shaft coupling failure during testing due to IGSCC in
May 2001. This failure is described in NRC Inspection Report No. 50-395/02-06, dated April 1,
2002 (ADAMS Accession No. ML020920543).
BACKGROUND
Applicable Regulatory DocumentsGeneral Design Criterion (GDC) 1 (defined in Appendix A to Title10 of the Code of FederalRegulations (10 CFR) Part 50, "Domestic Licensing of Production and Utilization Facilities,")and Criterion Xl (defined in Appendix B to 10 CFR Part 50) requires that all components (such
as pumps and valves) that are necessary for safe operation be tested to demonstrate that they
will perform satisfactorily in service. GDC 1 requires that components important to safety be
tested to quality standards that are commensurate with the importance of the safety function(s)
to be performed. Appendix B to 10 CFR Part 50 describes the requisite quality assurance
program, which includes testing for safety-related components. 10 CFR 50.55a defines the requirements for applying industry codes and standards to boiling orpressurized water-cooled nuclear power facilities. This section requires that certain American
Society of Mechanical Engineers Boiler and Vessel Pressure (ASME Code) Class 1, 2, and 3 pumps and valves be designed to enable inservice test (IST) and that testing be performed to
assess operational readiness in accordance with the ASME Code for Operation and
Maintenance of Nuclear Power Plants (OM Code). IST is intended to detect degradation
affecting operation and assess whether adequate margins are maintained. The OM Code
requires the licensee to show that the overall pump performance has not degraded from that
required to meet its intended function. Establishing limits that are more conservative than the
OM Code limits may be necessary to ensure that design limits are met. NRC IN 97-90
describes situations where ASME acceptance ranges were greater than those assumed in the
accident analysis. OM Code acceptance criteria do not supersede the requirements delineated
in a licensee's design or license basis. Components within the scope of 10 CFR 50.55a are included in the scope of 10 CFR 50.65,"Requirements for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants" (the
"Maintenance Rule"). The Maintenance Rule requires that licensees monitor the performance
or condition of structures, systems, or components (SSCs) against licensee-established goals
in a manner sufficient to provide reasonable assurance that such SSCs are capable of fulfilling
their intended function. Such goals are to be established, where practicable, commensurate
with safety, and they are to take into account industry-wide operating experience. When the
performance or condition of a component does not meet established goals, appropriate
corrective actions are to be taken.Operability limits of pumps must always meet, or be consistent with, licensing-basisassumptions in a plant's safety analysis. NRC Generic Letter 91-18 (replaced by
Regulatory Issue Summary 2005-20) provides additional guidance on operability of
components. NUREG-1482, Revision 1, "Guidelines for Inservice Testing at Nuclear Power Plants" provides licensees guidelines and recommendations for developing and implementingprograms for the IST of pumps and valves at commercial nuclear power plants.Applicable NRC Information NoticesNRC IN 93-68, "Failure of Pump Shaft Coupling Caused by Temper Embrittlement DuringManufacture," dated September 1, 1993, in part, described that type 410 stainless steel used in
the manufacture of Byron Jackson pump shaft couplings may have low-impact strength due to
inadequate heat treatment during manufacture, rendering the component susceptible to
tempering embrittlement. Pump shafts containing temper-embrittled couplings could fail during
operation if the pump has worn bearings, if the shaft is misaligned, or if shaft motion is impeded
by silt or debris ingestion. NRC IN 94-45, "Potential Common-Mode Failure Mechanism for Large Vertical Pumps," datedJune 17, 1994, described a problem where differing coupling materials could experience
galvanic corrosion resulting in a failure of the shaft coupling and subsequent failure of long
shaft vertical pumps. NRC IN 94-45 also generally addressed a concern that current testing
methodologies of vertical line shaft pump hydraulic and mechanical performance may not
identify interference, before damage occurs, between the pump impellers and bowls caused by
a change in shaft length. NRC IN 97-90, "Use of Nonconservative Acceptance Criteria in Safety-Related PumpSurveillance Tests," dated December 30, 1997, describes examples that identify inadequacies
in surveillance test procedure acceptance criteria that had the potential for, and in some cases
did result in, pumps not meeting their accident analysis acceptance criteria. Applicable NRC Inspection ProceduresNRC inspection guidance for SW pumps at operating nuclear plants is provided in: (1) Attachment 22, "Surveillance Testing," to NRC Inspection Manual IP 71111, "Reactor Safety:
Initiating Events, Mitigating Systems, Barrier Integrity," available on the NRC's public Web site
at: http://www.nrc.gov/reading-rm/doc-collections/insp-manual/inspection-procedure/index.html;and in (2) Inspection Procedure 73756, "IST of Pumps and Valves," July 27, 1995, available on
the NRC's public Web site at:
http://www.nrc.gov/reading-rm/doc-collections/insp-manual/inspection-procedure/ip73756.pdf
DISCUSSION
The SW pump shaft failure events at Columbia Generating Station and related industryoperating experience demonstrate that IST alone might not be sufficient to ensure that pumps
meet their accident analysis acceptance criteria. These failures might not be detected by
commonly employed condition monitoring, during routine operations, or from surveillance test or
IST results. Pump shaft and coupling failures can challenge operability even though
performance degradation over time may appear consistent with normal wear. Operating
experience also shows that pump shaft failures and coupling failures can result in sudden total
loss of flow before standard performance monitoring techniques alert plant staff to the
impending failure. Inspection and refurbishment of deep draft pumps on a periodic basis may
reveal some of these failure mechanisms. Vibration analysis using more sophisticated tools
(i.e., transducer on pump bowl, phase angle analysis) may be capable of identifying similar
future failures. Enhanced condition-monitoring techniques or time-based inspections, may
enhance early detection of degradation before failures in large vertical deep draft pumps occur.
CONTACT
S This IN requires no specific action or written response. Please direct any questions about thismatter to the technical contacts./TQuay for MCase/Michael J. Case, DirectorDivision of Policy & Rulemaking
Office of Nuclear Reactor RegulationTechnical Contacts: John McHale, NRR/DCI, 301-415-1261, JJM1@nrc.govTim Mitts, NRR/DIRS,
301-415-4067, TMM5@nrc.govNote: NRC generic communications may be found on the NRC public web site, http://www.nrc.gov under Electronic Reading Room/Document Collections.
CONTACT
S This IN requires no specific action or written response. Please direct any questions about thismatter to the technical contacts./TQuay for MCase/Michael J. Case, DirectorDivision of Policy & Rulemaking
Office of Nuclear Reactor RegulationTechnical Contacts: John McHale, NRR/DCI, 301-415-1261, JJM1@nrc.govTim Mitts, NRR/DIRS,
301-415-4067, TMM5@nrc.govNote: NRC generic communications may be found on the NRC public web site, http://www.nrc.gov under Electronic Reading Room/Document Collections.DISTRIBUTION
- IN Reading FileADAMS Accession Number: ML063110327OFFICEDIRS:IOEBDCI:CPTBTech.EditorTL:DIRS:IOEBNAMETMittsJMcHaleCbladey (by e-mail)JThorpDATE / /2007 11/13/200610/6/200611/17/2006 OFFICEPGCB:DPRPGCB:DPRADES:DSS:SBPBC:PGCB:DPRD:DPRNAMECHawes CMHJRobinsonJSegalaCJacksonMJCaseDATE 1/25/2007 12/19/200602/02/200702/08/200702/09/2007OFFICIAL RECORD COPY
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list | - Information Notice 2007-03, Reportable Medical Events Involving Patients Receiving Dosages of Sodium Iodide Iodine-131 Less than the Prescribed Dosage Because of Capsules Remaining in Vials After Administration (2 February 2007, Topic: Enforcement Discretion)
- Information Notice 2007-03, Reportable Medical Events Involving Patients Receiving Dosages of Sodium Iodide Iodine-131 Less Than the Prescribed Dosage Because of Capsules Remaining in Vials After Administration (2 February 2007, Topic: Tritium Exit Sign)
- Information Notice 2007-04, Construction Experience Related to the Assurance of Quality in the Construction of Nuclear Power Plants (5 February 2007)
- Information Notice 2007-05, Vertical Deep Draft Pump Shaft and Coupling Failures (9 February 2007, Topic: Ultimate heat sink)
- Information Notice 2007-06, Potential Common Cause Vulnerabilities in Essential Service Water Systems (9 February 2007, Topic: Ultimate heat sink, Probabilistic Risk Assessment, Coatings, Biofouling, Through-Wall Leak)
- Information Notice 2007-07, Potential Failure of All Control Rod Groups to Insert in a Boiling Water Reactor (BWR) Due to a Fire (15 February 2007, Topic: Hot Short, Safe Shutdown, Shutdown Margin, Fire Protection Program, Backfit)
- Information Notice 2007-08, Potential Vulnerabilities of Time-Reliant Computer-Based Systems Due to Change in Daylight Saving Time Dates (28 February 2007)
- Information Notice 2007-09, Equipment Operability Under Degraded Voltage Conditions (26 March 2007)
- Information Notice 2007-10, Yttritium-90 TheraSpheres and SirSpheres Impurities (2 March 2007, 15 March 2007, Topic: Tritium Exit Sign)
- Information Notice 2007-10, Yttritium-90 Theraspheres and Sirspheres Impurities (2 March 2007, Topic: Enforcement Discretion)
- Information Notice 2007-11, Recent Operator Performance Issues at Nuclear Power Plants (6 March 2007, Topic: Time of Discovery)
- Information Notice 2007-12, Tactical Communications Interoperability Between Nuclear Power Reactor Licensees and First Responders (15 March 2007)
- Information Notice 2007-14, Loss of Offsite Power and Dual-Unit Trip at Catawba Nuclear Generating Station (30 March 2007)
- Information Notice 2007-15, Effects of Ethernet-based, Non-Safety Related Controls on the Safe and Continued Operation of Nuclear Power Stations (17 April 2007)
- Information Notice 2007-17, Fires at Nuclear Power Plants Involving Inadequate Fire Protection Administrative and Design Controls (3 May 2007, Topic: Safe Shutdown, Fire Barrier, Operator Manual Action, Continuous fire watch, Fire Protection Program, Fire Watch, Hourly Fire Watch)
- Information Notice 2007-18, Operating Experience Regarding Entrainment of Gas or Debris Into Auxiliary Feedwater Systems (13 May 2007, Topic: Design basis earthquake)
- Information Notice 2007-18, Operating Experience Regarding Entrainment of Gas or Debris into Auxiliary Feedwater Systems (13 May 2007, Topic: Foreign Material Exclusion)
- Information Notice 2007-20, Use of Blank Ammunition (11 June 2007)
- Information Notice 2007-21, Pipe Wear Due to Interaction of Flow-Induced Vibration and Reflective Metal Insulation (11 December 2020, Topic: VT-2, Liquid penetrant)
- Information Notice 2007-22, Recent Hydrogen Fluoride Exposures at Fuel Cycle Facilities (19 June 2007)
- Information Notice 2007-23, Inadvertent Discharge of Halon 1301 Fire Suppression System Due to Incorrect and/or Out of Date Procedures (8 August 2007, Topic: Fire Protection Program)
- Information Notice 2007-23, Inadvertent Discharge of Halon 1301 Fire Suppression System Due to Incorrect And/Or Out of Date Procedures (8 August 2007, Topic: Fire Protection Program)
- Information Notice 2007-24, Summary of Fitness-for-Duty Program Performance Reports for Calendar Year 2006 (19 July 2007, Topic: Fitness for Duty, Contraband)
- Information Notice 2007-25, Recommendations From the Advisory Committee on the Medical Use of Isotopes for Improved Compliance with 10 CFR 35.40 and 35.27 (19 July 2007, Topic: Tritium Exit Sign)
- Information Notice 2007-25, Recommendations from the Advisory Committee on the Medical Use of Isotopes for Improved Compliance with 10 CFR 35.40 and 35.27 (19 July 2007, Topic: Enforcement Discretion)
- Information Notice 2007-26, E-mail from Alex Klein to Alex Marion Regarding NRC Information Notice 2007-26 (17 December 2007, Topic: Coatings)
- Information Notice 2007-27, Recurring Events and Trends Involving Emergency Diesel Generator Operability (6 August 2007, Topic: Preliminary White Finding)
- Information Notice 2007-28, Potential Common Cause Vulnerabilities in Essential Service Water Systems Due to Inadequate Chemistry Controls (19 September 2007, Topic: Probabilistic Risk Assessment, Frazil ice, Biofouling)
- Information Notice 2007-29, Temporary Scaffolding Affects Operability of Safety-Related Equipment (17 September 2007, Topic: Fire Protection Program, Scaffolding)
- Information Notice 2007-30, Radiological Controls Create Criticality Safety Accident Scenario for Fissile Solution Container Transport at Fuel Cycle Facility (13 September 2007, Topic: Coatings)
- Information Notice 2007-31, U.S. Food and Drug Administration Announcement Related to Sleep Disorder Drugs (13 November 2007, Topic: Fitness for Duty, Coatings)
- Information Notice 2007-32, Out of Service Equipment Connected to in Service Process Line Results in Fissile Solution Spill at Fuel Cycle Facility (15 October 2007, Topic: Hydrostatic, Coatings)
- Information Notice 2007-32, Out of Service Equipment Connected To In Service Process Line Results in Fissile Solution Spill at Fuel Cycle Facility (15 October 2007, Topic: Hydrostatic, Coatings)
- Information Notice 2007-34, Operating Experience Regarding Electrical Circuit Breakers (22 October 2007)
- Information Notice 2007-36, Emergency Diesel Generator Voltage Regulator Problems (15 November 2007)
- Information Notice 2007-37, Buildup of Deposits in Steam Generators (23 November 2007)
- Information Notice 2007-38, Ensuring Complete and Accurate Information in the Documentation of Training and Experience for Individuals Seeking Medical Authorization Under the Alternate Pathway (14 December 2007)
- Information Notice 2007-40, Inadequate Implementation of 10 CFR Part 21 Requirements by Vendors Who Supply Basic Components to Nuclear Power Plant Licensees (21 December 2007)
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