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{{#Wiki_filter:Dispositioning Information Related to Service Life of Installed Safety
{{#Wiki_filter:Dispositioning Information Related to Service Life of Installed Safety-Related SSCs Inspector Guidance June 2018
-Related SSCsJune 2018Inspector Guidance Objectives  
 
-This Guidance Will:
Objectives - This Guidance Will:
2 1.Assist inspectors in understanding issues related to how long safety-related Structures, Systems, Components (SSCs) remain in service 2.Clarify use of terminology 3.Clarify the applicability of various regulations and industry standards 4.Acknowledge issues related to service life that are not specifically covered by regulations 5.Describe a framework for inspectors to evaluate information related to service life  
: 1. Assist inspectors in understanding issues related to how long safety-related Structures, Systems, Components (SSCs) remain in service
-a.Identifying applicability and performance deficiencies b.Documenting findings under the ROP c.Avoiding unintended and undocumented backfits 6.Walk through examples of how to document findings Why is this training needed?
: 2. Clarify use of terminology
*The staff has noted multiple instances where the provisions of 10 CFR Part 50, Appendix B, TS, and other regulations were not met that pertained to how long SSCs remain in service before appropriate preventive maintenance activities were performed (refurbishment/replacement). In some cases, no preventive maintenance activities had been performed for equipment that was safety
: 3. Clarify the applicability of various regulations and industry standards
-related and not designated as run
: 4. Acknowledge issues related to service life that are not specifically covered by regulations
-to-failure.*In some instances, end-of-life failures resulted.3Failed capacitor bank  
: 5. Describe a framework for inspectors to evaluate information related to service life -
-end of life failures Why is this guidance needed? (cont'd)In general, when the licensee becomes aware of information relevant to safety
: a. Identifying applicability and performance deficiencies
-related equipment installed in the plant, the staff expects the licensee to determine applicability and disposition that information.
: b. Documenting findings under the ROP
*NRC regulatory requirements involving service life issues may involve several regulations, Appendix B and TS, among others. *Commitments made to the NRC, including self-imposed standards, licensee programs and procedures, are applicable to this training.4Age-related failure of a GE 200 amp breaker that was installed in a panel for over 30 years.
: c. Avoiding unintended and undocumented backfits
: 6. Walk through examples of how to document findings 2
 
Why is this training needed?
* The staff has noted multiple instances where the provisions of 10 CFR Part 50, Appendix B, TS, and other regulations were not met that pertained to how long SSCs remain in service before appropriate preventive maintenance activities were performed (refurbishment/replacement). In some cases, no preventive maintenance activities had been performed for equipment that was safety-related and not designated as run-to-failure.
* In some instances, end-of-life failures resulted.
Failed capacitor bank - end of life failures 3
 
Why is this guidance needed? (contd)
In general, when the licensee becomes aware of information relevant to safety-related equipment installed in the plant, the staff expects the licensee to determine applicability and disposition that information.
* NRC regulatory requirements involving service life issues may involve several regulations, Appendix B and TS, among others.
* Commitments made to the NRC, including self-imposed standards, licensee programs Age-related failure of a GE 200 amp and procedures, are applicable to this      breaker that was installed in a panel training.                                  for over 30 years.
4
 
Is Aging Bad?
Is Aging Bad?
*All SCCs age, and aging is an expected phenomenon.
* All SCCs age, and aging is an expected phenomenon.
*This guidance is focused on how SSCs are maintained over their installed life, particularly when the component is approaching end of life.
* This guidance is focused on how SSCs are maintained over their installed life, particularly when the component is approaching end of life.
*This guidance is also focused on end
* This guidance is also focused on end-of-life issues that can be brought about by equipment usage characteristics and operating conditions (e.g. number of cycles, voltage, current, temperature), and identified through the use of operating experience.
-of-life issues that can be brought about by equipment usage characteristics and operating conditions (e.g. number of cycles, voltage, current, temperature), and identified through the use of operating experience.
5
5 Background2012 IOEB Study Study noted increase in the number of findings and reportable events involving licensees operating equipment beyond its service life.
 
6IOEB Study  
===Background===
-ADAMS Accession No
2012 IOEB Study Study noted increase in the number of findings and reportable events involving licensees operating equipment beyond its service life.
.: ML13044A469 Information Notice 2012
6 IOEB Study - ADAMS Accession No.: ML13044A469
-06"Ineffective Use of Vendor Technical Recommendations"
 
*Informs addressees of operating experience regarding ineffective use of vendor recommendations
Background (contd)
*Discusses several events including a Calvert Cliffs dual-unit trip and subsequent emergency EDG failure to start The time-based replacement interval (recommended by the vendor) had been suspended, but no performance monitoring program was put in place 7Background (cont'd)
Information Notice 2012-06 Ineffective Use of Vendor Technical Recommendations
Service life issues may present themselves in different ways, and their treatment depends upon the particular circumstanceWhat are the Issues?
* Informs addressees of operating experience regarding ineffective use of vendor recommendations
8General Case (common)
* Discusses several events including a Calvert Cliffs dual-unit trip and subsequent emergency EDG failure to start The time-based replacement interval (recommended by the vendor) had been suspended, but no performance monitoring program was put in place 7
*Licensee becomes aware of information that could affect the service life of an SSC or its ability to continue to perform its safety function(s
 
)*Examples of information include but are not limited to vendor information, NRC generic communications, industry topical reports, and operating experience.Licensing Basis Case (less common)
What are the Issues?
:*Licensee becomes aware that a safety
Service life issues may present themselves in different ways, and their treatment depends upon the particular circumstance General Case (common):
-related SSC has been installed longer than the time period specified in their licensing basis documentation.
* Licensee becomes aware of information that could affect the service life of an SSC or its ability to continue to perform its safety function(s)
Is service life information considered "design basis" information, or information supporting the design?Analyzing the Issues 9*Often, service life information is neither design or licensing basis information. However, it generally is important information that the licensees needs to consider when developing appropriate preventive maintenance practices.
* Examples of information include but are not limited to vendor information, NRC generic communications, industry topical reports, and operating experience.
*In some instances, service life information that is considered part of the licensing basis should be further evaluated to determine its applicability to the design bases or supporting the design bases.
Licensing Basis Case (less common):
*Service life information may also be subject to other regulatory requirements.
* Licensee becomes aware that a safety-related SSC has been installed longer than the time period specified in their licensing basis documentation.                                                       8
*An example would be the UFSAR description of station vital batteries that have an expected service life of 20 years.
 
NRC inspectors should have a framework to ensure consistent use of terminology. While some of the terms used in this presentation do not have 10 CFR definitions, these terms are important in understanding how service life documentation impacts regulatory programs and requirements.Terminology 10*Information
Analyzing the Issues Is service life information considered design basis information, or information supporting the design?
*Service Life
* Often, service life information is neither design or licensing basis information. However, it generally is important information that the licensees needs to consider when developing appropriate preventive maintenance practices.
*Documented Service Life
* In some instances, service life information that is considered part of the licensing basis should be further evaluated to determine its applicability to the design bases or supporting the design bases.
*Awareness*Licensing Basis
* Service life information may also be subject to other regulatory requirements.
*Regulatory Commitments
* An example would be the UFSAR description of station vital batteries that have an expected service life of 20 years.                     9
*Quality Assurance program
 
*Licensee Procedures
Terminology NRC inspectors should have a framework to ensure consistent use of terminology. While some of the terms used in this presentation do not have 10 CFR definitions, these terms are important in understanding how service life documentation impacts regulatory programs and requirements.
*Operability and Functionality
* Information
*Non-conforming Terminology (Cont'd)(Examples of Information) 11"Information" can describe a mechanism or trait that may affect the ability of a safety
* Service Life
-related SSC to continue to perform its safety function(s). Information can come from a variety of sources. Some examples include:
* Documented Service Life
*Vendor Information
* Awareness
*Technical Bulletins
* Licensing Basis
*Letters*Service advisories
* Regulatory Commitments
*Manuals*NRC Generic Communications
* Quality Assurance program
*Industry Operating Experience (including plant specific/fleet)
* Licensee Procedures
*Industry Sources
* Operability and Functionality
*INPO*EPRI*Owners Groups
* Non-conforming 10
*Licensee engineering analyses Terminology (cont'd) 12*AwarenessKnowledge or perception of a situation or fact. Inspectors should take into account which entity in the licensee organization has possession of the information. If a field technician is aware, that is different than licensed operators or a shift manager being aware.*Licensing Basis The licensing basis is determined on a case
 
-by-case basis and is commonly referred to as the set of NRC requirements applicable to a specific facility and that licensee's written commitments for ensuring compliance with applicable NRC requirements in the licensing basis and the facility
Terminology (Contd)
-specific design bases (including all modifications and additions over the life of the license).
(Examples of Information)
Terminology (cont'd) 13*Non-conforming ConditionA condition of an SSC that involves a failure to meet the LB or a situation in which quality has been reduced because of factors such as improper design, testing, construction, or modification.
Information   can describe a mechanism or trait that may affect the ability of a safety-related SSC to continue to perform its safety function(s). Information can come from a variety of sources. Some examples include:
*ObligationAn enforceable regulatory requirement such as a rule, regulation, order, or operating license, including the technical specifications and license conditions.
* Vendor Information
Terminology (cont'd) 14*Regulatory CommitmentsActions proposed in writing by the licensee to be completed by a certain date. These are submitted in writing on the docket and in some cases can be modified without prior NRC approval.
* Technical Bulletins
*Quality Assurance Program (Plan)NRC approved, represents the licensee's interpretation of applicability of 10 CFR Appendix B to their station's operations.
* Letters
*Operability and FunctionalityTerms related to an SSC's ability to perform it's safety function(s). The NRC's guidance is contained in Inspection Manual Chapter 0326, "Operability Determinations & Functionality Assessments for Conditions Adverse to Quality or Safety."
* Service advisories
Terminology (cont'd) 15*Service LifeA term with various meanings based on context and situation. It is used to describe the period of time for which satisfactory performance can be demonstrated for a specific set of service conditions. Related terms include: qualified life, shelf life, designated life, design life, and installed life.
* Manuals
*Documented Service LifeFor the purposes of this training, this is the time period that the licensee documents in its program or procedures to determine how long an SSC can remain in service before refurbishment or replacement. This information may be vendor, licensee, or industry
* NRC Generic Communications
-generated, among other sources. Note: the existence of a vendor recommendation on service life does not necessarily mean the licensee is using that information as its documented service life. The licensee may be using other information, or it may not have a documented service life.
* Industry Operating Experience (including plant specific/fleet)
Applicable Regulations and Industry Standards 16STS 5.4.1, "Procedures," RG 1.33, "Quality Assurance Program Requirements" STS 5.4.1 states that "written procedures shall be established, implemented, and maintained covering the applicable procedures recommended in RG 1.33, Appendix A."
* Industry Sources
*Appendix A of RG 1.33 states that PM schedules should be developed to specify the replacement of items such as filters, strainers, wear rings (i.e., consummables).
* INPO
*Appendix A of RG 1.33 also lists typical activities that should be covered by procedures. Examples include repair/replacement of safety
* EPRI
-related equipment that is expected to need replacement over the life of the plant.
* Owners Groups
17NRC-Approved QA Program (Appendix B)
* Licensee engineering analyses 11
*The QA Program is required by the operating license
 
.*The QA Program follows the format and implements the requirements of 10 CFR Part 50, Appendix B
Terminology (contd)
.*The QA Program contains additional details and description not present in the regulation
* Awareness Knowledge or perception of a situation or fact. Inspectors should take into account which entity in the licensee organization has possession of the information. If a field technician is aware, that is different than licensed operators or a shift manager being aware.
.*Although nothing prohibits NRC inspectors from citing directly against the NRC
* Licensing Basis The licensing basis is determined on a case-by-case basis and is commonly referred to as the set of NRC requirements applicable to a specific facility and that licensees written commitments for ensuring compliance with applicable NRC requirements in the licensing basis and the facility-specific design bases (including all modifications and additions over the life of the license).
-approved QA Program, inspectors have historically cited directly against 10 CFR Part 50 Appendix B.  
12
*Determining the appropriate Appendix B criterion to cite against involves several factors (e.g.
 
-nature of the PD, primary cause related to procedural compliance, repetitiveness, justification for continued service)Applicable Regulations and Industry Standards (cont'd) 18Corrective Action Program (CAP) and licensee's screening process
Terminology (contd)
*Most if not all licensees have a screening process for determining whether information is applicable to the site.*Some licensees may not have an information screening process to determine applicability but may employ other programs, (e.g. operating experience), to determine if information requires corrective action.  
* Non-conforming Condition A condition of an SSC that involves a failure to meet the LB or a situation in which quality has been reduced because of factors such as improper design, testing, construction, or modification.
*For information that requires corrective action, licensees would use their QA program, CAP, and operability/functionality process to properly disposition the information.Applicable Regulations and Industry Standards (cont'd
* Obligation An enforceable regulatory requirement such as a rule, regulation, order, or operating license, including the technical specifications and license conditions.
)
13
 
Terminology (contd)
* Regulatory Commitments Actions proposed in writing by the licensee to be completed by a certain date. These are submitted in writing on the docket and in some cases can be modified without prior NRC approval.
* Quality Assurance Program (Plan)
NRC approved, represents the licensees interpretation of applicability of 10 CFR Appendix B to their stations operations.
* Operability and Functionality Terms related to an SSCs ability to perform its safety function(s).
The NRCs guidance is contained in Inspection Manual Chapter 0326, Operability Determinations & Functionality Assessments for Conditions Adverse to Quality or Safety.
14
 
Terminology (contd)
* Service Life A term with various meanings based on context and situation. It is used to describe the period of time for which satisfactory performance can be demonstrated for a specific set of service conditions. Related terms include: qualified life, shelf life, designated life, design life, and installed life.
* Documented Service Life For the purposes of this training, this is the time period that the licensee documents in its program or procedures to determine how long an SSC can remain in service before refurbishment or replacement. This information may be vendor, licensee, or industry-generated, among other sources.
Note: the existence of a vendor recommendation on service life does not necessarily mean the licensee is using that information as its documented service life. The licensee may be using other information, or it may not have a documented service life.
15
 
Applicable Regulations and Industry Standards STS 5.4.1, Procedures, RG 1.33, Quality Assurance Program Requirements STS 5.4.1 states that written procedures shall be established, implemented, and maintained covering the applicable procedures recommended in RG 1.33, Appendix A.
* Appendix A of RG 1.33 states that PM schedules should be developed to specify the replacement of items such as filters, strainers, wear rings (i.e., consummables).
* Appendix A of RG 1.33 also lists typical activities that should be covered by procedures. Examples include repair/replacement of safety-related equipment that is expected to need replacement over the life of the plant.
16
 
Applicable Regulations and Industry Standards (contd)
NRC-Approved QA Program (Appendix B)
* The QA Program is required by the operating license.
* The QA Program follows the format and implements the requirements of 10 CFR Part 50, Appendix B.
* The QA Program contains additional details and description not present in the regulation.
* Although nothing prohibits NRC inspectors from citing directly against the NRC-approved QA Program, inspectors have historically cited directly against 10 CFR Part 50 Appendix B.
* Determining the appropriate Appendix B criterion to cite against involves several factors (e.g.- nature of the PD, primary cause related to procedural compliance, repetitiveness, justification for continued service)       17
 
Applicable Regulations and Industry Standards (contd)
Corrective Action Program (CAP) and licensees screening process
* Most if not all licensees have a screening process for determining whether information is applicable to the site.
* Some licensees may not have an information screening process to determine applicability but may employ other programs, (e.g. operating experience),
to determine if information requires corrective action.
* For information that requires corrective action, licensees would use their QA program, CAP, and operability/functionality process to properly disposition the information.                           18
 
Applicable Regulations and Industry Standards (cont.)
Applicable Regulations and Industry Standards (cont.)
1910 CFR 50.49, "Environmental qualification of electric equipment important to safety for nuclear power plants"
10 CFR 50.49, Environmental qualification of electric equipment important to safety for nuclear power plants
*10 CFR 50.49 requirements are relatively narrow and prescriptive
* 10 CFR 50.49 requirements are relatively narrow and prescriptive
*10 CFR 50.49 states that an SSC covered by this regulation [i.e., safety
* 10 CFR 50.49 states that an SSC covered by this regulation [i.e., safety-related electrical equipment installed in a harsh environment] must perform its safety function up to the end of its qualified life.
-related electrical equipment installed in a harsh environment] must perform its safety function up to the end of its qualified life.
* The term qualified life has meaning in 10 CFR 50.49 as it applies to electrical equipment installed in a harsh environment. This should not be confused with the term 19 service life as used in this training.
*The term "qualified life" has meaning in 10 CFR 50.49 as it applies to electrical equipment installed in a harsh environment. This should not be confused with the term "service life" as used in this training.
 
20IEEE-323, "IEEE Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations"
Related Regulations and Industry Standards (contd)
*Class 1E SSCs are typically qualified for environmental and seismic conditions in accordance with IEEE
IEEE-323, IEEE Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations
-323.*Although staff regulatory guides endorse IEEE
* Class 1E SSCs are typically qualified for environmental and seismic conditions in accordance with IEEE-323.
-323, and many licensees commit to the guidance contained within, the use of IEEE Standard 323 is not required by regulation.
* Although staff regulatory guides endorse IEEE-323, and many licensees commit to the guidance contained within, the use of IEEE Standard 323 is not required by regulation.
*IEEE-323 and its associated regulatory guidance do not require licensees to define a specific service life or design life for safety
* IEEE-323 and its associated regulatory guidance do not require licensees to define a specific service life or design life for safety-related SSCs in mild environments.
-related SSCs in mild environments.Related Regulations and Industry Standards (cont'd)  
20
*The Maintenance Rule (MR) has a role in monitoring trends and preventing adverse performance in SSCs.
 
*While the MR is a requirement, compliance with it does not relieve licensees of the need to screen information that may impact how long SSCs can remain in service
Role of the Maintenance Rule (10 CFR 50.65)
.*The MR is not intended to prevent all failures. It is intended to address licensee
* The Maintenance Rule (MR) has a role in monitoring trends and preventing adverse performance in SSCs.
-set performance monitoring goals and standards.*A misconception of the MR is that compliance with the rule (alone) will alert licensees as to when an SSC needs refurbishment or replacement.
* While the MR is a requirement, compliance with it does not relieve licensees of the need to screen information that may impact how long SSCs can remain in service.
21Role of the Maintenance Rule (10 CFR 50.65) 22*Absent a performance history, the MR does not mandate licensees to do anything different just because equipment is old. However, the MR does set expectations for periodically reviewing established performance goals and consideration of industry
* The MR is not intended to prevent all failures. It is intended to address licensee-set performance monitoring goals and standards.
-wide operating experience. (see 50.65(a)(3)).
* A misconception of the MR is that compliance with the rule (alone) will alert licensees as to when an SSC needs refurbishment or replacement.
*The determination of what operating experience needs to be incorporated is up to the licensee.  
21
*Note that some SSCs do not exhibit adverse performance before failure. Thus, licensees should not rely only on the MR to inform them of when to refurbish or replace equipment.Role of the Maintenance Rule (10 CFR 50.65) (Cont.)
 
23*On a case by case basis, licensees can determine through evaluation that certain SSCs may be designated as "run
Role of the Maintenance Rule (10 CFR 50.65)
-to-failure" if they meet specific criteria as outlined in NUMARC 93
(Cont.)
-01, and as endorsed by RG 1.160 (e.g., the failure provides little or no contribution to system safety function) ("run-to-maintenance" is another related term used by the industry
* Absent a performance history, the MR does not mandate licensees to do anything different just because equipment is old. However, the MR does set expectations for periodically reviewing established performance goals and consideration of industry-wide operating experience. (see 50.65(a)(3)).
)*Inspectors should understand and be familiar with a licensee's specific criteria for determining how SSCs can be run
* The determination of what operating experience needs to be incorporated is up to the licensee.
-to-failure relative to the staff
* Note that some SSCs do not exhibit adverse performance before failure. Thus, licensees should not rely only on the MR to inform them of when to refurbish or replace equipment.                                                 22
-endorsed procedural guidance (e.g., NUMARC 93-01).Role of the Maintenance Rule (10 CFR 50.65) (Cont.)
 
Are Licensees Required to Define a Service Life for All Safety
Role of the Maintenance Rule (10 CFR 50.65) (Cont.)
-Related SSCs?
* On a case by case basis, licensees can determine through evaluation that certain SSCs may be designated as run-to-failure if they meet specific criteria as outlined in NUMARC 93-01, and as endorsed by RG 1.160 (e.g., the failure provides little or no contribution to system safety function) (run-to-maintenance is another related term used by the industry)
24However, some exceptions/additional requirements exist:
* Inspectors should understand and be familiar with a licensees specific criteria for determining how SSCs can be run-to-failure relative to the staff-endorsed procedural guidance (e.g.,
*10 CFR 50.49 (qualified life of electrical equipment in harsh environment)
NUMARC 93-01).
*Other licensing bases (e.g., UFSAR) that define or list replacement/refurbishment intervals
23
*Aging management programs (e.g., License Renewal) that are incorporated into a plant's licensing basisNo. There is no regulatory requirement to define replacement/refurbishment intervals for all safety
 
-related SSCs.
Are Licensees Required to Define a Service Life for All Safety-Related SSCs?
Are Licensees Required to Define a Service Life for All Safety
No. There is no regulatory requirement to define replacement/refurbishment intervals for all safety-related SSCs.
-Related SSCs? (cont.)
However, some exceptions/additional requirements exist:
25Other considerations include:
* 10 CFR 50.49 (qualified life of electrical equipment in harsh environment)
*There are SSCs installed during original plant licensing that were procured without service life documentation. However, it is the responsibility of the licensee to provide assurances that safety
* Other licensing bases (e.g., UFSAR) that define or list replacement/refurbishment intervals
-related SSCs can perform their function over the life of the plant.
* Aging management programs (e.g., License Renewal) that are incorporated into a plants licensing basis                                        24
*Many SSCs areinstalled in the plant with a documented service life or service life information available to the licensee. This service life information may be vendor, licensee, or industry
 
-generated and may be contained or referenced in plant procedures, vendor manuals, UFSAR, or other licensee documents. *Licensees who elect to deviate from the "documented" service life should have a basis for doing so. Instances where there is no basis should be further pursued by the inspector to understand if the preventive maintenance approach is appropriate.
Are Licensees Required to Define a Service Life for All Safety-Related SSCs? (cont.)
If the licensee becomes aware of information that challenges the presumption that a safety
Other considerations include:
-related SSC can continue to perform its safety function(s), the inspector should:  
* There are SSCs installed during original plant licensing that were procured without service life documentation. However, it is the responsibility of the licensee to provide assurances that safety-related SSCs can perform their function over the life of the plant.
*Assess the licensee's use of their applicability/screening process to determine if the information is applicable to the facility.
* Many SSCs are installed in the plant with a documented service life or service life information available to the licensee. This service life information may be vendor, licensee, or industry-generated and may be contained or referenced in plant procedures, vendor manuals, UFSAR, or other licensee documents.
*For information that is applicable to the site, ensure the licensee dispositions the information in accordance with their NRC
* Licensees who elect to deviate from the documented service life should have a basis for doing so. Instances where there is no basis should be further pursued by the inspector to understand if the preventive maintenance approach is appropriate.
-approved QA program, corrective action program, and operability/functionality determination process, as appropriate.
25
26Inspector Guidance If a licensee becomes aware that a safety
 
-related SSC has been installed in the plant for longer than the amount of time described by the plant's licensing basis documentation, the inspector should:
Inspector Guidance If the licensee becomes aware of information that challenges the presumption that a safety-related SSC can continue to perform its safety function(s), the inspector should:
*Determine if the licensee has assessed whether the SSC can continue to be relied on to perform its intended safety
* Assess the licensees use of their applicability/screening process to determine if the information is applicable to the facility.
-related function(s) consistent with its licensing basis and NRC requirements.
* For information that is applicable to the site, ensure the licensee dispositions the information in accordance with their NRC-approved QA program, corrective action program, and operability/functionality determination process, as appropriate.
*Determine if the licensee has documented their assessment prior to exceeding the time period documented in the licensing basis because it avoids the potential need to disposition a non
26
-conforming condition.  
 
*Evaluate whether the situation represents a non
Inspector Guidance (cont.)
-conforming condition that should be dispositioned using the licensee's operability process.
If a licensee becomes aware that a safety-related SSC has been installed in the plant for longer than the amount of time described by the plants licensing basis documentation, the inspector should:
27Inspector Guidance (cont.)
* Determine if the licensee has assessed whether the SSC can continue to be relied on to perform its intended safety-related function(s) consistent with its licensing basis and NRC requirements.
* Determine if the licensee has documented their assessment prior to exceeding the time period documented in the licensing basis because it avoids the potential need to disposition a non-conforming condition.
* Evaluate whether the situation represents a non-conforming condition that should be dispositioned using the licensees operability process.
27
 
Inspector Guidance (cont.)
There are several situations in which an inspector may wish to investigate an issue further:
There are several situations in which an inspector may wish to investigate an issue further:
*When evaluating the licensee's determination of the cause of a component failure or degraded performance
* When evaluating the licensees determination of the cause of a component failure or degraded performance
*During extent of condition reviews
* During extent of condition reviews
*Maintenance effectiveness review
* Maintenance effectiveness review
*During a component or system design review 28Inspector Guidance (cont.)
* During a component or system design review 28
Inspector Guidance (cont.)Investigation of component or system failure  
 
-questions to ask
Inspector Guidance (cont.)
*Was the failure age
Investigation of component or system failure -
-related?*What information did the licensee possess pertaining to how long the SSC could remain in service?*If equipment was operated beyond this time period, did the licensee justify continued service through appropriate documentation?
questions to ask
*Did the licensee take into account available site
* Was the failure age-related?
-specific or industry operating experience when deciding to operate equipment beyond its service life?29 Investigation of an SSC that is being operated beyond its documented service life:*What information are licensees relying on to justify operability/functionality and continued service? Have they documented their assessment of the information? Where do they believe they are on the Bathtub Curve?
* What information did the licensee possess pertaining to how long the SSC could remain in service?
*Are licensees relying solely on a clean performance history (i.e., no failures) to justify operability/functionality or continued service beyond documented service life?*How does the component fail (i.e., after noticeable degradation, or without warning)?30Inspector Guidance (cont.)
* If equipment was operated beyond this time period, did the licensee justify continued service through appropriate documentation?
Investigation of an SSC that is being operated beyond its documented service life (cont'd):
* Did the licensee take into account available site-specific or industry operating experience when deciding to operate equipment beyond its service life?
*Is the licensee using "generic" industry preventive maintenance templates to determine replacement/refurbishment intervals without customizing that guidance for how the SSC is being used at the plant? Did it account for local environmental conditions, such as enclosed conditions, local/accident temperatures, humidity, operating pressures, etc.), Did it account for how the component is actually used (e.g., always energized/only energized when operating, etc.)?Was site-specific and industry operating experience, including vendor guidance, considered?
29
31Inspector Guidance (cont.)
 
In reviewing service life issues, inspectors should identify the applicable requirement to avoid unintended and undocumented backfits.The list below represents the most often used regulations for citing service life issues in a mild environment:
Inspector Guidance (cont.)
*STS 5.4.1/R.G. 1.33
Investigation of an SSC that is being operated beyond its documented service life:
*10 CFR Part 50 Appendix B Criterion V
* What information are licensees relying on to justify operability/functionality and continued service? Have they documented their assessment of the information?
*10 CFR Part 50 Appendix B Criterion XVI
Where do they believe they are on the Bathtub Curve?
*10 CFR Part 50 Appendix B Criterion III*10 CFR Part 50.65 ('Maintenance Rule')
* Are licensees relying solely on a clean performance history (i.e., no failures) to justify operability/functionality or continued service beyond documented service life?
32Documenting Inspection Results  
* How does the component fail (i.e., after noticeable degradation, or without warning)?
*Non-compliance with the Technical Specifications (STS 5.4.1/R.G. 1.33)Missing-procedures are incomplete or do not exist Deficient-procedures contain errors or lack specificity (i.e., lack of adequate guidance for the repair/replacement of SSCs that have a defined life)Failure to adhere
30
-procedures are adequate, but the licensee is not following them 33Documenting Inspection Results Enforcement (cont'd)Quality Assurance Program
 
*Appendix B, Criterion V, ProceduresMissing-procedures are incomplete or do not existDeficient-procedures contain errors or lack specificityFailure to adhere
Inspector Guidance (cont.)
-procedures are adequate, but the licensee is not following them 34Documenting Inspection Results Enforcement (cont'd)Quality Assurance Program
Investigation of an SSC that is being operated beyond its documented service life (contd):
*Appendix B, Criterion XVI, Corrective ActionInadequate corrective actions to address a condition adverse to quality (CAQ). Failure(s) that occur as a result of previous events where ineffective corrective action resulted from age
* Is the licensee using generic industry preventive maintenance templates to determine replacement/refurbishment intervals without customizing that guidance for how the SSC is being used at the plant?
-related degradation, as a result of an SSC exceeding its documented service life.
Did it account for local environmental conditions, such as enclosed conditions, local/accident temperatures, humidity, operating pressures, etc.),
35Documenting Inspection Results Enforcement (cont'd)Quality Assurance Program
Did it account for how the component is actually used (e.g., always energized/only energized when operating, etc.)?
*Appendix B, Criterion III, Design ControlFailure to translate appropriate design standards into procedures and instructions (i.e., the expected service life/design life of an SSC addressed in the licensing basis)Failure to address or maintain the qualified life of Class 1E electrical SSCs located in a harsh environmentFailure to adequately address design/operating characteristics that reduce the expected life of an SSC 36Documenting Inspection Results Enforcement (cont'd)It is not appropriate to cite App B, Criterion III for a failure to adhere to vendor information, as there is no regulatory requirement to adhere to vendor information, unless it is incorporated in the licensing basis.
Was site-specific and industry operating experience, including vendor guidance, considered?
37Documenting Inspection Results Enforcement (cont'd)
31
*Other Regulations If the performance deficiency reflects non
 
-compliance with 10 CFR 50.49 (Environmental Qualification of Electric Equipment Important to Safety for NPP), 10 CFR 50.65 (Maintenance Rule), 10 CFR 54.37 (License Renewal Recordkeeping Requirements), or other regulation(s), inspectors should consider the most appropriate basis for documenting the issue.
Documenting Inspection Results In reviewing service life issues, inspectors should identify the applicable requirement to avoid unintended and undocumented backfits.
38Documenting Inspection Results (cont'd)
The list below represents the most often used regulations for citing service life issues in a mild environment:
Enforcement (cont'd)
* STS 5.4.1/R.G. 1.33
*Nonsafety-related SSCsPerformance deficiencies involving nonsafety
* 10 CFR Part 50 Appendix B Criterion V
-related SSCs regarding how long the SSC can remain in service may not constitute a violation of regulatory requirements, but may still result in an inspection finding.These types of issues are usually cited against failure to adhere to defined licensee programs (e.g., preventive maintenance program guidance) or failure to adhere to approved procedural guidance.
* 10 CFR Part 50 Appendix B Criterion XVI
39Documenting Inspection Results (cont'd)
* 10 CFR Part 50 Appendix B Criterion III
Potential Scenario 40The following slides explain a potential scenario of how a licensee might become aware of information affecting the capability of safety
* 10 CFR Part 50.65 (Maintenance Rule) 32
-related SSC to perform its design function(s). The scenario includes recommendations for inspector actions and dispositioning the information. Main steps in the process include:
 
*NRC inspector identifies information potentially relevant to the licensee*Inspector verifies licensee awareness or makes them aware
Documenting Inspection Results
*Licensee/inspector identify what process the licensee is in for determining applicability
* Non-compliance with the Technical Specifications (STS 5.4.1/R.G. 1.33)
*Licensee makes applicability determination
Missing - procedures are incomplete or do not exist Deficient - procedures contain errors or lack specificity (i.e., lack of adequate guidance for the repair/replacement of SSCs that have a defined life)
*Proper dispositioning of applicable information
Failure to adhere - procedures are adequate, but the licensee is not following them 33
*Licensee determines necessary actions and timeframes for those actions*NRC inspectors evaluate the licensee's disposition and proposed actions Potential Scenario (cont'd)Step 1:*NRC inspector identifies information potentially relevant to the licensee.*Inspector may come across the information in a variety of waysLetter (from a vendor or elsewhere)Design Basis documentationOperating experience (event report, Part 21, etc.)Licensee-generated 41 Potential Scenario (cont'd)Step 2:*NRC inspector verifies that the licensee is aware of the information or makes them aware:Inspector should ensure that licensee awareness is at the appropriate level for getting the information into the right process.
 
42 Potential Scenario (cont'd)Step 3:Licensee/inspector identify what process the licensee is in for determining applicability
Documenting Inspection Results Enforcement (contd)
:*Does the licensee have an 'applicability' process?
Quality Assurance Program
*If no, then another process can be used to disposition the information (CAP, Operability, Vendor Information, Operating Experience, etc.)
* Appendix B, Criterion V, Procedures Missing - procedures are incomplete or do not exist Deficient - procedures contain errors or lack specificity Failure to adhere - procedures are adequate, but the licensee is not following them 34
*Processes should drive towards documentation of licensee's decision 43 Potential Scenario (cont'd)Step 4:Licensee makes applicability determination:
 
*NRC inspector should verify rigor of applicability determination process. Examples:Consider whether a BWR issue is potentially applicable to PWRs?Problem identified on one component model may be applicable to similar components
Documenting Inspection Results Enforcement (contd)
*Is licensee's scope for determining applicable appropriately broad/open
Quality Assurance Program
-minded?44 Potential Scenario (cont'd)Step 5:Licensee determines necessary actions and timeframes for those actions. Possible considerations include:
* Appendix B, Criterion XVI, Corrective Action Inadequate corrective actions to address a condition adverse to quality (CAQ).
*Is there an applicable regulatory requirement?
Failure(s) that occur as a result of previous events where ineffective corrective action resulted from age-related degradation, as a result of an SSC exceeding its documented service life.
*Does the issue involve a licensing basis document (e.g. UFSAR) or a licensee program (e.g. QA, Maint. Rule, Environmental Qualification)?
35
*Is there an applicable licensee procedure?
 
*If the licensee determines no action is required, it should have justification for the decision (e.g. technical evaluation) [if it determines it to be a run to failure component (i.e., also known as run to maintenance) is it following MR guidance for RTF?]
Documenting Inspection Results Enforcement (contd)
45 Example 1The licensee becomes aware of a vendor technical manual which states that the replacement/refurbishment interval for a safety
Quality Assurance Program
-related SSC is 5 years shorter than the interval it is currently using in their preventive maintenance program. The licensee has no technical analysis that justifies the difference in intervals.
* Appendix B, Criterion III, Design Control Failure to translate appropriate design standards into procedures and instructions (i.e., the expected service life/design life of an SSC addressed in the licensing basis)
*Case 1-The licensee uses its applicability/screening process to determine that the information is applicable to the site. The licensee decides to change the replacement/refurbishment interval for the SSC.  
Failure to address or maintain the qualified life of Class 1E electrical SSCs located in a harsh environment Failure to adequately address design/operating characteristics that reduce the expected life of an SSC         36
*Case 2-The licensee uses its applicability/screening process to determine that the information is applicable to the site. The licensee decides not to change the replacement/refurbishment interval for the SSC. *Case 3-The licensee uses its applicability/screening process to determine that the information is not applicable to the site, and that no changes to the replacement/refurbishment interval are needed.
 
46 Guidance for Resolving Case 1Case 1The licensee uses their applicability/screening process to determine that the information is applicable to the site. The licensee decides to change the replacement/refurbishment interval for the SSC.  
Documenting Inspection Results Enforcement (contd)
*The inspector should verify that the licensee properly dispositions the information in accordance with their programs (QA, CAP, Operability/Functionality
It is not appropriate to cite App B, Criterion III for a failure to adhere to vendor information, as there is no regulatory requirement to adhere to vendor information, unless it is incorporated in the licensing basis.
).*The inspector should be aware of any procedure or program changes planned by the licensee.
37
*The inspector should consider this issue for a future sample selection when performing the next Problem Identification and Resolution inspection.
 
47 Guidance for Resolving Case 2Case 2The licensee uses their applicability/screening process to determine that the information is applicable to the site, and dispositions the information in accordance with their programs (QA, CAP, Operability/Functionality). The licensee decides not to changethe replacement/refurbishment interval for the SSC (or if one does not exist, to establish one).  
Documenting Inspection Results (contd)
*The inspector should review this record in the licensee's CAP to determine the licensee's rationale for taking no action.
Enforcement (contd)
*If the licensee documented a reasonable technical justification for choosing not to change their replacement/refurbishment interval, the inspector need not take further action.  
* Other Regulations If the performance deficiency reflects non-compliance with 10 CFR 50.49 (Environmental Qualification of Electric Equipment Important to Safety for NPP), 10 CFR 50.65 (Maintenance Rule), 10 CFR 54.37 (License Renewal Recordkeeping Requirements), or other regulation(s), inspectors should consider the most appropriate basis for documenting the issue.
*If the licensee did not document a reasonable technical evaluation or otherwise justify taking no action, then the inspector should inquire as to the licensee's basis for ensuring the component can continue to perform its safety function.
38
48 Guidance for Resolving Case 2Case 2(cont.)*If the licensee is relying on surveillance and testing alone to justify continued service, then further inquiry is necessary.
 
*Surveillance and testing alone (unless used in conjunction with other factors, such as engineering analysis, site
Documenting Inspection Results (contd)
-specific and industry OpE, vendor information, etc.), may not provide adequate assurance that the component can continue to perform its safety
Enforcement (contd)
-related function for the life of the plant. In such cases, a licensee should have procedural guidance as to when to refurbish/replace equipment before expected failure.
* Nonsafety-related SSCs Performance deficiencies involving nonsafety-related SSCs regarding how long the SSC can remain in service may not constitute a violation of regulatory requirements, but may still result in an inspection finding.
*The inspector should look for procedural requirements or commitments that have established an expectation of periodic refurbishment or replacement (e.g. STS 5.4.1/RG 1.33, QA program, or site
These types of issues are usually cited against failure to adhere to defined licensee programs (e.g., preventive maintenance program guidance) or failure to adhere to approved procedural guidance.
-specific PM procedures, among other information).  
39
*It is not appropriate to run 'critical' SSCs to failure. [i.e., run
 
-to-failure, as discussed in NUMARC 93
Potential Scenario The following slides explain a potential scenario of how a licensee might become aware of information affecting the capability of safety-related SSC to perform its design function(s). The scenario includes recommendations for inspector actions and dispositioning the information. Main steps in the process include:
-01]49 Guidance for Resolving Case 3Case 3*The licensee uses their applicability/screening process to determine that the information is not applicable to the site, and that no changes to the replacement/refurbishment interval are needed.*The inspector should verify the licensee's basis for their decision 50 Example 2The licensee has incorporated the industry-generated preventive maintenance template for a component type. The preventive maintenance template allows the licensee to choose a replacement/refurbishment interval from among a range of values. The licensee has chosen an interval that is different from the vendor
* NRC inspector identifies information potentially relevant to the licensee
-supplied documentation, without an accompanying plant
* Inspector verifies licensee awareness or makes them aware
-specific evaluation or assessment.
* Licensee/inspector identify what process the licensee is in for determining applicability
51 Guidance for Resolving Example 2
* Licensee makes applicability determination
*Industry-generated PM templates are generic guidance and should not be used without adapting the template to the plant-specific situation.
* Proper dispositioning of applicable information
*If the licensee is applying an industry
* Licensee determines necessary actions and timeframes for those actions
-generated PM template, the inspector should verify that the licensee has properly considered/incorporated relevant factors, such as:
* NRC inspectors evaluate the licensees disposition and proposed actions 40
*Site and industry operating experience, *Local environmental factors (humidity, pressure, temperature, radiation, etc.), *Vendor information  
 
*Industry/utility advocacy group guidance (e.g., BWROG/PWROG/RUG/NSIAC/INPO) 52 Guidance for Resolving Example 2
Potential Scenario (contd)
*If the licensee has reasonably considered applicable factors, and this approach is documented, then the inspector should determine if the approach is reasonable.
Step 1:
*If the engineering justification/approach is reasonable, then no further action may be warranted.
* NRC inspector identifies information potentially relevant to the licensee.
*If the justification does not appear reasonable, then the inspector should question the licensee's approach for making their determination. This may involve requesting additional documentation.
* Inspector may come across the information in a variety of ways Letter (from a vendor or elsewhere)
*After evaluating any additional information, the inspector must determine whether the licensee's justification is inadequate and constitutes a performance deficiency.
Design Basis documentation Operating experience (event report, Part 21, etc.)
53 Real World Example 1
Licensee-generated 41
*An emergency diesel generator tripped on overcurrent during a test run. The overcurrent condition was caused by a failed diode in the generator excitation circuit which was known to experience elevated temperatures during operation. This was a repetitive failure which had occurred on several other occasions at this site. *Industry operating experience was available which stated that the average life span for EDG excitation system diodes was 12 years. The operating experience also recommended that licensee's review EDG diodes subjected to elevated temperatures during operation and adjust the scope or frequency of the preventive maintenance programs accordingly. *The licensee screened this information into their corrective action program, but closed the entry without taking any action. *The licensee's procedures stated in part that industry operating experience, corrective maintenance history and SSC performance "shall be considered when developing the overall maintenance strategy for equipment within the scope of the preventive maintenance program."
 
54 Real World Example 1Inspection Outcome
Potential Scenario (contd)
*Inspectors identified a condition adverse to quality based on the elevated temperature of the diodes during diesel operation, which had been previously identified by the industry and was known to shorten diode service life.
Step 2:
*Inspectors cited the licensee against T.S. 5.4.1 (Procedures, RG 1.33) for failure to incorporate relevant operating experience into the preventive maintenance program as required by station procedures.
* NRC inspector verifies that the licensee is aware of the information or makes them aware:
*Inspectors cited the licensee against Appendix B Criterion XVI for their failure to correct a condition adverse to quality associated with elevated operating temperatures of EDG excitation system diodes. *These performance deficiencies resulted in a White finding.
Inspector should ensure that licensee awareness is at the appropriate level for getting the information into the right process.
55 Real World Example 2
42
*An emergency diesel generator tripped on low coolant pressure during a test run. A flexible coupling hose had ruptured due to age-related degradation. The licensee's investigation revealed that the hose had been installed for 22 years.*Maintenance procedure originally aligned with vendor recommendations and required hose replacement every ten years.*Later, licensee revised procedure (without adequate justification) to required hose replacement "if leaking."*Additionally, the licensee made further changes as a result of corrective actions for an unrelated EDG failure to replace non
 
-metallic flexible hoses every 12 years.
Potential Scenario (contd)
56 Real World Example 2Inspection Outcome
Step 3:
*The inspectors identified a White finding and associated violation of 10 CFR 50, Appendix B, Criterion V, "Instructions, Procedures, and Drawings," because the licensee did not provide appropriate maintenance instructions to ensure the EDG cooling flexible coupling hose was maintained to ensure adequate cooling to support the EDG No. 1 safety function.
Licensee/inspector identify what process the licensee is in for determining applicability:
57 Questions?Contact: John Thompson, IOEB/DIRS/NRR(301) 415-1011 58}}
* Does the licensee have an applicability process?
* If no, then another process can be used to disposition the information (CAP, Operability, Vendor Information, Operating Experience, etc.)
* Processes should drive towards documentation of licensees decision 43
 
Potential Scenario (contd)
Step 4:
Licensee makes applicability determination:
* NRC inspector should verify rigor of applicability determination process. Examples:
Consider whether a BWR issue is potentially applicable to PWRs?
Problem identified on one component model may be applicable to similar components
* Is licensees scope for determining applicable appropriately broad/open-minded?
44
 
Potential Scenario (contd)
Step 5:
Licensee determines necessary actions and timeframes for those actions. Possible considerations include:
* Is there an applicable regulatory requirement?
* Does the issue involve a licensing basis document (e.g.
UFSAR) or a licensee program (e.g. QA, Maint. Rule, Environmental Qualification)?
* Is there an applicable licensee procedure?
* If the licensee determines no action is required, it should have justification for the decision (e.g. technical evaluation)
[if it determines it to be a run to failure component (i.e.,
also known as run to maintenance) is it following MR guidance for RTF?]
45
 
Example 1 The licensee becomes aware of a vendor technical manual which states that the replacement/refurbishment interval for a safety-related SSC is 5 years shorter than the interval it is currently using in their preventive maintenance program. The licensee has no technical analysis that justifies the difference in intervals.
* Case 1 - The licensee uses its applicability/screening process to determine that the information is applicable to the site. The licensee decides to change the replacement/refurbishment interval for the SSC.
* Case 2 - The licensee uses its applicability/screening process to determine that the information is applicable to the site. The licensee decides not to change the replacement/refurbishment interval for the SSC.
* Case 3 - The licensee uses its applicability/screening process to determine that the information is not applicable to the site, and that no changes to the replacement/refurbishment interval are needed.
46
 
Guidance for Resolving Case 1 Case 1 The licensee uses their applicability/screening process to determine that the information is applicable to the site. The licensee decides to change the replacement/refurbishment interval for the SSC.
* The inspector should verify that the licensee properly dispositions the information in accordance with their programs (QA, CAP, Operability/Functionality).
* The inspector should be aware of any procedure or program changes planned by the licensee.
* The inspector should consider this issue for a future sample selection when performing the next Problem Identification and Resolution inspection.
47
 
Guidance for Resolving Case 2 Case 2 The licensee uses their applicability/screening process to determine that the information is applicable to the site, and dispositions the information in accordance with their programs (QA, CAP, Operability/Functionality). The licensee decides not to change the replacement/refurbishment interval for the SSC (or if one does not exist, to establish one).
* The inspector should review this record in the licensees CAP to determine the licensees rationale for taking no action.
* If the licensee documented a reasonable technical justification for choosing not to change their replacement/refurbishment interval, the inspector need not take further action.
* If the licensee did not document a reasonable technical evaluation or otherwise justify taking no action, then the inspector should inquire as to the licensees basis for ensuring the component can continue to perform its safety function.                         48
 
Guidance for Resolving Case 2 Case 2 (cont.)
* If the licensee is relying on surveillance and testing alone to justify continued service, then further inquiry is necessary.
* Surveillance and testing alone (unless used in conjunction with other factors, such as engineering analysis, site-specific and industry OpE, vendor information, etc.), may not provide adequate assurance that the component can continue to perform its safety-related function for the life of the plant. In such cases, a licensee should have procedural guidance as to when to refurbish/replace equipment before expected failure.
* The inspector should look for procedural requirements or commitments that have established an expectation of periodic refurbishment or replacement (e.g. STS 5.4.1/RG 1.33, QA program, or site-specific PM procedures, among other information).
* It is not appropriate to run critical SSCs to failure. [i.e., run-to-failure, as discussed in NUMARC 93-01]                               49
 
Guidance for Resolving Case 3 Case 3
* The licensee uses their applicability/screening process to determine that the information is not applicable to the site, and that no changes to the replacement/refurbishment interval are needed.
* The inspector should verify the licensees basis for their decision 50
 
Example 2 The licensee has incorporated the industry-generated preventive maintenance template for a component type. The preventive maintenance template allows the licensee to choose a replacement/refurbishment interval from among a range of values. The licensee has chosen an interval that is different from the vendor-supplied documentation, without an accompanying plant-specific evaluation or assessment.
51
 
Guidance for Resolving Example 2
* Industry-generated PM templates are generic guidance and should not be used without adapting the template to the plant-specific situation.
* If the licensee is applying an industry-generated PM template, the inspector should verify that the licensee has properly considered/incorporated relevant factors, such as:
* Site and industry operating experience,
* Local environmental factors (humidity, pressure, temperature, radiation, etc.),
* Vendor information
* Industry/utility advocacy group guidance (e.g.,
BWROG/PWROG/RUG/NSIAC/INPO) 52
 
Guidance for Resolving Example 2
* If the licensee has reasonably considered applicable factors, and this approach is documented, then the inspector should determine if the approach is reasonable.
* If the engineering justification/approach is reasonable, then no further action may be warranted.
* If the justification does not appear reasonable, then the inspector should question the licensees approach for making their determination. This may involve requesting additional documentation.
* After evaluating any additional information, the inspector must determine whether the licensees justification is inadequate and constitutes a performance deficiency.
53
 
Real World Example 1
* An emergency diesel generator tripped on overcurrent during a test run. The overcurrent condition was caused by a failed diode in the generator excitation circuit which was known to experience elevated temperatures during operation.
This was a repetitive failure which had occurred on several other occasions at this site.
* Industry operating experience was available which stated that the average life span for EDG excitation system diodes was 12 years. The operating experience also recommended that licensees review EDG diodes subjected to elevated temperatures during operation and adjust the scope or frequency of the preventive maintenance programs accordingly.
* The licensee screened this information into their corrective action program, but closed the entry without taking any action.
* The licensees procedures stated in part that industry operating experience, corrective maintenance history and SSC performance shall be considered when developing the overall maintenance strategy for equipment within the scope of the preventive maintenance program.
54
 
Real World Example 1 Inspection Outcome
* Inspectors identified a condition adverse to quality based on the elevated temperature of the diodes during diesel operation, which had been previously identified by the industry and was known to shorten diode service life.
* Inspectors cited the licensee against T.S. 5.4.1 (Procedures, RG 1.33) for failure to incorporate relevant operating experience into the preventive maintenance program as required by station procedures.
* Inspectors cited the licensee against Appendix B Criterion XVI for their failure to correct a condition adverse to quality associated with elevated operating temperatures of EDG excitation system diodes.
* These performance deficiencies resulted in a White finding.
55
 
Real World Example 2
* An emergency diesel generator tripped on low coolant pressure during a test run. A flexible coupling hose had ruptured due to age-related degradation. The licensees investigation revealed that the hose had been installed for 22 years.
* Maintenance procedure originally aligned with vendor recommendations and required hose replacement every ten years.
* Later, licensee revised procedure (without adequate justification) to required hose replacement if leaking.
* Additionally, the licensee made further changes as a result of corrective actions for an unrelated EDG failure to replace non-metallic flexible hoses every 12 years.
56
 
Real World Example 2 Inspection Outcome
* The inspectors identified a White finding and associated violation of 10 CFR 50, Appendix B, Criterion V, Instructions, Procedures, and Drawings, because the licensee did not provide appropriate maintenance instructions to ensure the EDG cooling flexible coupling hose was maintained to ensure adequate cooling to support the EDG No. 1 safety function.
57
 
Questions?
Contact: John Thompson, IOEB/DIRS/NRR (301) 415-1011 58}}

Revision as of 20:00, 20 October 2019

Inspector Guidance (Training) on Service Life Issues
ML18219A470
Person / Time
Issue date: 08/07/2018
From: Jacqueline Thompson
NRC/NRR/DIRS/IOEB
To:
Thompson J, NRR/DIRS, 415-1011
References
Download: ML18219A470 (58)


Text

Dispositioning Information Related to Service Life of Installed Safety-Related SSCs Inspector Guidance June 2018

Objectives - This Guidance Will:

1. Assist inspectors in understanding issues related to how long safety-related Structures, Systems, Components (SSCs) remain in service
2. Clarify use of terminology
3. Clarify the applicability of various regulations and industry standards
4. Acknowledge issues related to service life that are not specifically covered by regulations
5. Describe a framework for inspectors to evaluate information related to service life -
a. Identifying applicability and performance deficiencies
b. Documenting findings under the ROP
c. Avoiding unintended and undocumented backfits
6. Walk through examples of how to document findings 2

Why is this training needed?

  • The staff has noted multiple instances where the provisions of 10 CFR Part 50, Appendix B, TS, and other regulations were not met that pertained to how long SSCs remain in service before appropriate preventive maintenance activities were performed (refurbishment/replacement). In some cases, no preventive maintenance activities had been performed for equipment that was safety-related and not designated as run-to-failure.
  • In some instances, end-of-life failures resulted.

Failed capacitor bank - end of life failures 3

Why is this guidance needed? (contd)

In general, when the licensee becomes aware of information relevant to safety-related equipment installed in the plant, the staff expects the licensee to determine applicability and disposition that information.

  • NRC regulatory requirements involving service life issues may involve several regulations, Appendix B and TS, among others.
  • Commitments made to the NRC, including self-imposed standards, licensee programs Age-related failure of a GE 200 amp and procedures, are applicable to this breaker that was installed in a panel training. for over 30 years.

4

Is Aging Bad?

  • All SCCs age, and aging is an expected phenomenon.
  • This guidance is focused on how SSCs are maintained over their installed life, particularly when the component is approaching end of life.
  • This guidance is also focused on end-of-life issues that can be brought about by equipment usage characteristics and operating conditions (e.g. number of cycles, voltage, current, temperature), and identified through the use of operating experience.

5

Background

2012 IOEB Study Study noted increase in the number of findings and reportable events involving licensees operating equipment beyond its service life.

6 IOEB Study - ADAMS Accession No.: ML13044A469

Background (contd)

Information Notice 2012-06 Ineffective Use of Vendor Technical Recommendations

  • Informs addressees of operating experience regarding ineffective use of vendor recommendations
  • Discusses several events including a Calvert Cliffs dual-unit trip and subsequent emergency EDG failure to start The time-based replacement interval (recommended by the vendor) had been suspended, but no performance monitoring program was put in place 7

What are the Issues?

Service life issues may present themselves in different ways, and their treatment depends upon the particular circumstance General Case (common):

  • Licensee becomes aware of information that could affect the service life of an SSC or its ability to continue to perform its safety function(s)
  • Examples of information include but are not limited to vendor information, NRC generic communications, industry topical reports, and operating experience.

Licensing Basis Case (less common):

  • Licensee becomes aware that a safety-related SSC has been installed longer than the time period specified in their licensing basis documentation. 8

Analyzing the Issues Is service life information considered design basis information, or information supporting the design?

  • Often, service life information is neither design or licensing basis information. However, it generally is important information that the licensees needs to consider when developing appropriate preventive maintenance practices.
  • In some instances, service life information that is considered part of the licensing basis should be further evaluated to determine its applicability to the design bases or supporting the design bases.
  • Service life information may also be subject to other regulatory requirements.
  • An example would be the UFSAR description of station vital batteries that have an expected service life of 20 years. 9

Terminology NRC inspectors should have a framework to ensure consistent use of terminology. While some of the terms used in this presentation do not have 10 CFR definitions, these terms are important in understanding how service life documentation impacts regulatory programs and requirements.

  • Information
  • Service Life
  • Documented Service Life
  • Awareness
  • Licensing Basis
  • Regulatory Commitments
  • Quality Assurance program
  • Licensee Procedures
  • Operability and Functionality
  • Non-conforming 10

Terminology (Contd)

(Examples of Information)

Information can describe a mechanism or trait that may affect the ability of a safety-related SSC to continue to perform its safety function(s). Information can come from a variety of sources. Some examples include:

  • Vendor Information
  • Technical Bulletins
  • Letters
  • Service advisories
  • Manuals
  • NRC Generic Communications
  • Industry Operating Experience (including plant specific/fleet)
  • Industry Sources
  • Owners Groups
  • Licensee engineering analyses 11

Terminology (contd)

  • Awareness Knowledge or perception of a situation or fact. Inspectors should take into account which entity in the licensee organization has possession of the information. If a field technician is aware, that is different than licensed operators or a shift manager being aware.
  • Licensing Basis The licensing basis is determined on a case-by-case basis and is commonly referred to as the set of NRC requirements applicable to a specific facility and that licensees written commitments for ensuring compliance with applicable NRC requirements in the licensing basis and the facility-specific design bases (including all modifications and additions over the life of the license).

12

Terminology (contd)

  • Non-conforming Condition A condition of an SSC that involves a failure to meet the LB or a situation in which quality has been reduced because of factors such as improper design, testing, construction, or modification.
  • Obligation An enforceable regulatory requirement such as a rule, regulation, order, or operating license, including the technical specifications and license conditions.

13

Terminology (contd)

  • Regulatory Commitments Actions proposed in writing by the licensee to be completed by a certain date. These are submitted in writing on the docket and in some cases can be modified without prior NRC approval.
  • Quality Assurance Program (Plan)

NRC approved, represents the licensees interpretation of applicability of 10 CFR Appendix B to their stations operations.

  • Operability and Functionality Terms related to an SSCs ability to perform its safety function(s).

The NRCs guidance is contained in Inspection Manual Chapter 0326, Operability Determinations & Functionality Assessments for Conditions Adverse to Quality or Safety.

14

Terminology (contd)

  • Service Life A term with various meanings based on context and situation. It is used to describe the period of time for which satisfactory performance can be demonstrated for a specific set of service conditions. Related terms include: qualified life, shelf life, designated life, design life, and installed life.
  • Documented Service Life For the purposes of this training, this is the time period that the licensee documents in its program or procedures to determine how long an SSC can remain in service before refurbishment or replacement. This information may be vendor, licensee, or industry-generated, among other sources.

Note: the existence of a vendor recommendation on service life does not necessarily mean the licensee is using that information as its documented service life. The licensee may be using other information, or it may not have a documented service life.

15

Applicable Regulations and Industry Standards STS 5.4.1, Procedures, RG 1.33, Quality Assurance Program Requirements STS 5.4.1 states that written procedures shall be established, implemented, and maintained covering the applicable procedures recommended in RG 1.33, Appendix A.

  • Appendix A of RG 1.33 states that PM schedules should be developed to specify the replacement of items such as filters, strainers, wear rings (i.e., consummables).
  • Appendix A of RG 1.33 also lists typical activities that should be covered by procedures. Examples include repair/replacement of safety-related equipment that is expected to need replacement over the life of the plant.

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Applicable Regulations and Industry Standards (contd)

NRC-Approved QA Program (Appendix B)

  • The QA Program is required by the operating license.
  • The QA Program contains additional details and description not present in the regulation.
  • Although nothing prohibits NRC inspectors from citing directly against the NRC-approved QA Program, inspectors have historically cited directly against 10 CFR Part 50 Appendix B.
  • Determining the appropriate Appendix B criterion to cite against involves several factors (e.g.- nature of the PD, primary cause related to procedural compliance, repetitiveness, justification for continued service) 17

Applicable Regulations and Industry Standards (contd)

Corrective Action Program (CAP) and licensees screening process

  • Most if not all licensees have a screening process for determining whether information is applicable to the site.
  • Some licensees may not have an information screening process to determine applicability but may employ other programs, (e.g. operating experience),

to determine if information requires corrective action.

  • For information that requires corrective action, licensees would use their QA program, CAP, and operability/functionality process to properly disposition the information. 18

Applicable Regulations and Industry Standards (cont.)

10 CFR 50.49, Environmental qualification of electric equipment important to safety for nuclear power plants

  • 10 CFR 50.49 requirements are relatively narrow and prescriptive
  • 10 CFR 50.49 states that an SSC covered by this regulation [i.e., safety-related electrical equipment installed in a harsh environment] must perform its safety function up to the end of its qualified life.
  • The term qualified life has meaning in 10 CFR 50.49 as it applies to electrical equipment installed in a harsh environment. This should not be confused with the term 19 service life as used in this training.

Related Regulations and Industry Standards (contd)

IEEE-323, IEEE Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations

  • Class 1E SSCs are typically qualified for environmental and seismic conditions in accordance with IEEE-323.
  • Although staff regulatory guides endorse IEEE-323, and many licensees commit to the guidance contained within, the use of IEEE Standard 323 is not required by regulation.
  • IEEE-323 and its associated regulatory guidance do not require licensees to define a specific service life or design life for safety-related SSCs in mild environments.

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Role of the Maintenance Rule (10 CFR 50.65)

  • The Maintenance Rule (MR) has a role in monitoring trends and preventing adverse performance in SSCs.
  • While the MR is a requirement, compliance with it does not relieve licensees of the need to screen information that may impact how long SSCs can remain in service.
  • The MR is not intended to prevent all failures. It is intended to address licensee-set performance monitoring goals and standards.
  • A misconception of the MR is that compliance with the rule (alone) will alert licensees as to when an SSC needs refurbishment or replacement.

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Role of the Maintenance Rule (10 CFR 50.65)

(Cont.)

  • Absent a performance history, the MR does not mandate licensees to do anything different just because equipment is old. However, the MR does set expectations for periodically reviewing established performance goals and consideration of industry-wide operating experience. (see 50.65(a)(3)).
  • The determination of what operating experience needs to be incorporated is up to the licensee.
  • Note that some SSCs do not exhibit adverse performance before failure. Thus, licensees should not rely only on the MR to inform them of when to refurbish or replace equipment. 22

Role of the Maintenance Rule (10 CFR 50.65) (Cont.)

  • On a case by case basis, licensees can determine through evaluation that certain SSCs may be designated as run-to-failure if they meet specific criteria as outlined in NUMARC 93-01, and as endorsed by RG 1.160 (e.g., the failure provides little or no contribution to system safety function) (run-to-maintenance is another related term used by the industry)
  • Inspectors should understand and be familiar with a licensees specific criteria for determining how SSCs can be run-to-failure relative to the staff-endorsed procedural guidance (e.g.,

NUMARC 93-01).

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Are Licensees Required to Define a Service Life for All Safety-Related SSCs?

No. There is no regulatory requirement to define replacement/refurbishment intervals for all safety-related SSCs.

However, some exceptions/additional requirements exist:

  • 10 CFR 50.49 (qualified life of electrical equipment in harsh environment)
  • Other licensing bases (e.g., UFSAR) that define or list replacement/refurbishment intervals

Are Licensees Required to Define a Service Life for All Safety-Related SSCs? (cont.)

Other considerations include:

  • There are SSCs installed during original plant licensing that were procured without service life documentation. However, it is the responsibility of the licensee to provide assurances that safety-related SSCs can perform their function over the life of the plant.
  • Many SSCs are installed in the plant with a documented service life or service life information available to the licensee. This service life information may be vendor, licensee, or industry-generated and may be contained or referenced in plant procedures, vendor manuals, UFSAR, or other licensee documents.
  • Licensees who elect to deviate from the documented service life should have a basis for doing so. Instances where there is no basis should be further pursued by the inspector to understand if the preventive maintenance approach is appropriate.

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Inspector Guidance If the licensee becomes aware of information that challenges the presumption that a safety-related SSC can continue to perform its safety function(s), the inspector should:

  • Assess the licensees use of their applicability/screening process to determine if the information is applicable to the facility.
  • For information that is applicable to the site, ensure the licensee dispositions the information in accordance with their NRC-approved QA program, corrective action program, and operability/functionality determination process, as appropriate.

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Inspector Guidance (cont.)

If a licensee becomes aware that a safety-related SSC has been installed in the plant for longer than the amount of time described by the plants licensing basis documentation, the inspector should:

  • Determine if the licensee has assessed whether the SSC can continue to be relied on to perform its intended safety-related function(s) consistent with its licensing basis and NRC requirements.
  • Determine if the licensee has documented their assessment prior to exceeding the time period documented in the licensing basis because it avoids the potential need to disposition a non-conforming condition.
  • Evaluate whether the situation represents a non-conforming condition that should be dispositioned using the licensees operability process.

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Inspector Guidance (cont.)

There are several situations in which an inspector may wish to investigate an issue further:

  • When evaluating the licensees determination of the cause of a component failure or degraded performance
  • During extent of condition reviews
  • Maintenance effectiveness review
  • During a component or system design review 28

Inspector Guidance (cont.)

Investigation of component or system failure -

questions to ask

  • Was the failure age-related?
  • What information did the licensee possess pertaining to how long the SSC could remain in service?
  • If equipment was operated beyond this time period, did the licensee justify continued service through appropriate documentation?
  • Did the licensee take into account available site-specific or industry operating experience when deciding to operate equipment beyond its service life?

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Inspector Guidance (cont.)

Investigation of an SSC that is being operated beyond its documented service life:

  • What information are licensees relying on to justify operability/functionality and continued service? Have they documented their assessment of the information?

Where do they believe they are on the Bathtub Curve?

  • Are licensees relying solely on a clean performance history (i.e., no failures) to justify operability/functionality or continued service beyond documented service life?
  • How does the component fail (i.e., after noticeable degradation, or without warning)?

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Inspector Guidance (cont.)

Investigation of an SSC that is being operated beyond its documented service life (contd):

  • Is the licensee using generic industry preventive maintenance templates to determine replacement/refurbishment intervals without customizing that guidance for how the SSC is being used at the plant?

Did it account for local environmental conditions, such as enclosed conditions, local/accident temperatures, humidity, operating pressures, etc.),

Did it account for how the component is actually used (e.g., always energized/only energized when operating, etc.)?

Was site-specific and industry operating experience, including vendor guidance, considered?

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Documenting Inspection Results In reviewing service life issues, inspectors should identify the applicable requirement to avoid unintended and undocumented backfits.

The list below represents the most often used regulations for citing service life issues in a mild environment:

Documenting Inspection Results

  • Non-compliance with the Technical Specifications (STS 5.4.1/R.G. 1.33)

Missing - procedures are incomplete or do not exist Deficient - procedures contain errors or lack specificity (i.e., lack of adequate guidance for the repair/replacement of SSCs that have a defined life)

Failure to adhere - procedures are adequate, but the licensee is not following them 33

Documenting Inspection Results Enforcement (contd)

Quality Assurance Program

  • Appendix B, Criterion V, Procedures Missing - procedures are incomplete or do not exist Deficient - procedures contain errors or lack specificity Failure to adhere - procedures are adequate, but the licensee is not following them 34

Documenting Inspection Results Enforcement (contd)

Quality Assurance Program

Failure(s) that occur as a result of previous events where ineffective corrective action resulted from age-related degradation, as a result of an SSC exceeding its documented service life.

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Documenting Inspection Results Enforcement (contd)

Quality Assurance Program

  • Appendix B, Criterion III, Design Control Failure to translate appropriate design standards into procedures and instructions (i.e., the expected service life/design life of an SSC addressed in the licensing basis)

Failure to address or maintain the qualified life of Class 1E electrical SSCs located in a harsh environment Failure to adequately address design/operating characteristics that reduce the expected life of an SSC 36

Documenting Inspection Results Enforcement (contd)

It is not appropriate to cite App B, Criterion III for a failure to adhere to vendor information, as there is no regulatory requirement to adhere to vendor information, unless it is incorporated in the licensing basis.

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Documenting Inspection Results (contd)

Enforcement (contd)

  • Other Regulations If the performance deficiency reflects non-compliance with 10 CFR 50.49 (Environmental Qualification of Electric Equipment Important to Safety for NPP), 10 CFR 50.65 (Maintenance Rule), 10 CFR 54.37 (License Renewal Recordkeeping Requirements), or other regulation(s), inspectors should consider the most appropriate basis for documenting the issue.

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Documenting Inspection Results (contd)

Enforcement (contd)

  • Nonsafety-related SSCs Performance deficiencies involving nonsafety-related SSCs regarding how long the SSC can remain in service may not constitute a violation of regulatory requirements, but may still result in an inspection finding.

These types of issues are usually cited against failure to adhere to defined licensee programs (e.g., preventive maintenance program guidance) or failure to adhere to approved procedural guidance.

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Potential Scenario The following slides explain a potential scenario of how a licensee might become aware of information affecting the capability of safety-related SSC to perform its design function(s). The scenario includes recommendations for inspector actions and dispositioning the information. Main steps in the process include:

  • NRC inspector identifies information potentially relevant to the licensee
  • Inspector verifies licensee awareness or makes them aware
  • Licensee/inspector identify what process the licensee is in for determining applicability
  • Licensee makes applicability determination
  • Proper dispositioning of applicable information
  • Licensee determines necessary actions and timeframes for those actions
  • NRC inspectors evaluate the licensees disposition and proposed actions 40

Potential Scenario (contd)

Step 1:

  • NRC inspector identifies information potentially relevant to the licensee.
  • Inspector may come across the information in a variety of ways Letter (from a vendor or elsewhere)

Design Basis documentation Operating experience (event report, Part 21, etc.)

Licensee-generated 41

Potential Scenario (contd)

Step 2:

  • NRC inspector verifies that the licensee is aware of the information or makes them aware:

Inspector should ensure that licensee awareness is at the appropriate level for getting the information into the right process.

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Potential Scenario (contd)

Step 3:

Licensee/inspector identify what process the licensee is in for determining applicability:

  • Does the licensee have an applicability process?
  • If no, then another process can be used to disposition the information (CAP, Operability, Vendor Information, Operating Experience, etc.)
  • Processes should drive towards documentation of licensees decision 43

Potential Scenario (contd)

Step 4:

Licensee makes applicability determination:

  • NRC inspector should verify rigor of applicability determination process. Examples:

Consider whether a BWR issue is potentially applicable to PWRs?

Problem identified on one component model may be applicable to similar components

  • Is licensees scope for determining applicable appropriately broad/open-minded?

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Potential Scenario (contd)

Step 5:

Licensee determines necessary actions and timeframes for those actions. Possible considerations include:

  • Is there an applicable regulatory requirement?
  • Does the issue involve a licensing basis document (e.g.

UFSAR) or a licensee program (e.g. QA, Maint. Rule, Environmental Qualification)?

  • Is there an applicable licensee procedure?
  • If the licensee determines no action is required, it should have justification for the decision (e.g. technical evaluation)

[if it determines it to be a run to failure component (i.e.,

also known as run to maintenance) is it following MR guidance for RTF?]

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Example 1 The licensee becomes aware of a vendor technical manual which states that the replacement/refurbishment interval for a safety-related SSC is 5 years shorter than the interval it is currently using in their preventive maintenance program. The licensee has no technical analysis that justifies the difference in intervals.

  • Case 1 - The licensee uses its applicability/screening process to determine that the information is applicable to the site. The licensee decides to change the replacement/refurbishment interval for the SSC.
  • Case 2 - The licensee uses its applicability/screening process to determine that the information is applicable to the site. The licensee decides not to change the replacement/refurbishment interval for the SSC.
  • Case 3 - The licensee uses its applicability/screening process to determine that the information is not applicable to the site, and that no changes to the replacement/refurbishment interval are needed.

46

Guidance for Resolving Case 1 Case 1 The licensee uses their applicability/screening process to determine that the information is applicable to the site. The licensee decides to change the replacement/refurbishment interval for the SSC.

  • The inspector should verify that the licensee properly dispositions the information in accordance with their programs (QA, CAP, Operability/Functionality).
  • The inspector should be aware of any procedure or program changes planned by the licensee.
  • The inspector should consider this issue for a future sample selection when performing the next Problem Identification and Resolution inspection.

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Guidance for Resolving Case 2 Case 2 The licensee uses their applicability/screening process to determine that the information is applicable to the site, and dispositions the information in accordance with their programs (QA, CAP, Operability/Functionality). The licensee decides not to change the replacement/refurbishment interval for the SSC (or if one does not exist, to establish one).

  • The inspector should review this record in the licensees CAP to determine the licensees rationale for taking no action.
  • If the licensee documented a reasonable technical justification for choosing not to change their replacement/refurbishment interval, the inspector need not take further action.
  • If the licensee did not document a reasonable technical evaluation or otherwise justify taking no action, then the inspector should inquire as to the licensees basis for ensuring the component can continue to perform its safety function. 48

Guidance for Resolving Case 2 Case 2 (cont.)

  • If the licensee is relying on surveillance and testing alone to justify continued service, then further inquiry is necessary.
  • Surveillance and testing alone (unless used in conjunction with other factors, such as engineering analysis, site-specific and industry OpE, vendor information, etc.), may not provide adequate assurance that the component can continue to perform its safety-related function for the life of the plant. In such cases, a licensee should have procedural guidance as to when to refurbish/replace equipment before expected failure.
  • The inspector should look for procedural requirements or commitments that have established an expectation of periodic refurbishment or replacement (e.g. STS 5.4.1/RG 1.33, QA program, or site-specific PM procedures, among other information).
  • It is not appropriate to run critical SSCs to failure. [i.e., run-to-failure, as discussed in NUMARC 93-01] 49

Guidance for Resolving Case 3 Case 3

  • The licensee uses their applicability/screening process to determine that the information is not applicable to the site, and that no changes to the replacement/refurbishment interval are needed.
  • The inspector should verify the licensees basis for their decision 50

Example 2 The licensee has incorporated the industry-generated preventive maintenance template for a component type. The preventive maintenance template allows the licensee to choose a replacement/refurbishment interval from among a range of values. The licensee has chosen an interval that is different from the vendor-supplied documentation, without an accompanying plant-specific evaluation or assessment.

51

Guidance for Resolving Example 2

  • Industry-generated PM templates are generic guidance and should not be used without adapting the template to the plant-specific situation.
  • If the licensee is applying an industry-generated PM template, the inspector should verify that the licensee has properly considered/incorporated relevant factors, such as:
  • Site and industry operating experience,
  • Local environmental factors (humidity, pressure, temperature, radiation, etc.),
  • Vendor information
  • Industry/utility advocacy group guidance (e.g.,

BWROG/PWROG/RUG/NSIAC/INPO) 52

Guidance for Resolving Example 2

  • If the licensee has reasonably considered applicable factors, and this approach is documented, then the inspector should determine if the approach is reasonable.
  • If the engineering justification/approach is reasonable, then no further action may be warranted.
  • If the justification does not appear reasonable, then the inspector should question the licensees approach for making their determination. This may involve requesting additional documentation.
  • After evaluating any additional information, the inspector must determine whether the licensees justification is inadequate and constitutes a performance deficiency.

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Real World Example 1

  • An emergency diesel generator tripped on overcurrent during a test run. The overcurrent condition was caused by a failed diode in the generator excitation circuit which was known to experience elevated temperatures during operation.

This was a repetitive failure which had occurred on several other occasions at this site.

  • Industry operating experience was available which stated that the average life span for EDG excitation system diodes was 12 years. The operating experience also recommended that licensees review EDG diodes subjected to elevated temperatures during operation and adjust the scope or frequency of the preventive maintenance programs accordingly.
  • The licensee screened this information into their corrective action program, but closed the entry without taking any action.
  • The licensees procedures stated in part that industry operating experience, corrective maintenance history and SSC performance shall be considered when developing the overall maintenance strategy for equipment within the scope of the preventive maintenance program.

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Real World Example 1 Inspection Outcome

  • Inspectors identified a condition adverse to quality based on the elevated temperature of the diodes during diesel operation, which had been previously identified by the industry and was known to shorten diode service life.
  • Inspectors cited the licensee against T.S. 5.4.1 (Procedures, RG 1.33) for failure to incorporate relevant operating experience into the preventive maintenance program as required by station procedures.
  • Inspectors cited the licensee against Appendix B Criterion XVI for their failure to correct a condition adverse to quality associated with elevated operating temperatures of EDG excitation system diodes.
  • These performance deficiencies resulted in a White finding.

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Real World Example 2

  • An emergency diesel generator tripped on low coolant pressure during a test run. A flexible coupling hose had ruptured due to age-related degradation. The licensees investigation revealed that the hose had been installed for 22 years.
  • Maintenance procedure originally aligned with vendor recommendations and required hose replacement every ten years.
  • Later, licensee revised procedure (without adequate justification) to required hose replacement if leaking.
  • Additionally, the licensee made further changes as a result of corrective actions for an unrelated EDG failure to replace non-metallic flexible hoses every 12 years.

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Real World Example 2 Inspection Outcome

  • The inspectors identified a White finding and associated violation of 10 CFR 50, Appendix B, Criterion V, Instructions, Procedures, and Drawings, because the licensee did not provide appropriate maintenance instructions to ensure the EDG cooling flexible coupling hose was maintained to ensure adequate cooling to support the EDG No. 1 safety function.

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Questions?

Contact: John Thompson, IOEB/DIRS/NRR (301) 415-1011 58