View source for US vs International LTO

==Equipment Reliability Process==
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The IAEA Safety Standard [https://www.iaea.org/publications/12240/ageing-management-and-development-of-a-programme-for-long-term-operation-of-nuclear-power-plants SSG-48] states that all systems, structures, and components (SSCs) within the scope of the aging management (AM) should be managed.  This includes components with [[LR_Application_Process#Screening| active and/or passive functions]].

The components with active functions historically have been the most challenging and, therefore, nuclear power plants (NPPs) carry out a wide scope of activities aimed at assessing the condition of their active components. These activities may be based on the maintenance rule, surveillance and testing, preventive and/or predictive maintenance of systems and equipment, reliability or lifecycle of components, or various combinations thereof. INPO [https://web.inpo.org/Pages/Equipment-Reliability.aspx AP-913](WANO [https://members.wano.org/library/tpm-member-support/wano-guidelines/gl-2018-02-rev-1-equipment-reliability-(1) GL 2018-02])  "Equipment Reliability Process"] was created to bring all these activities together into a process that identifies, organizes, and integrates them to maximize their efficiency and effectiveness.

The integration and coordination of all the above-mentioned activities ensures a high level of reliability of plant equipment, whether in operation or newly installed. To achieve this goal, the Equipment Reliability (ER) process was established allowing plant personnel to assess the condition of plant equipment, develop and implement long-term maintenance plans, monitor individual equipment or system performance, and make ongoing adjustments to predictive and preventive maintenance tasks and frequencies based on operating experience more easily.

The [https://pr.epri.com/PR/ERWG Equipment Reliability Working Group (ERWG)] and International Equipment Reliability Working Group (IERWG) are industry stakeholder groups chartered to advance industry efforts in advancing ER processes and are supported by EPRI as listed on [https://pr.epri.com/PR Plant Reliability and Resilience (PRR) - Equipment Reliability (ER) and Related Processes Wiki].

Based on the information presented in the [[US_vs_International_LTO#Objectives| objectives]] as well as the [[US_vs_International_LTO#Methodology| methodology]] of the ER process, the following image summarizes the objectives, benefits, and impact of implementing an Equipment Reliability process in a new or existing plant.

[[File:Subpage-10-Figure-1.png|thumb|800 px|center|Objectives, Benefits and Impact of an Equipment Reliability Process]]

===Objectives===
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The ER process is based on the implementation and development of an Equipment and System Reliability Monitoring and Improvement Plan for the entire NPP. It integrates several existing monitoring activities into a common objective: to achieve reliability targets as high as practical, in order to "eliminate critical component failures" and "maintain acceptable levels of reliability for noncritical components".

The main objectives of an ER process could be summarized as follows:
<ol style="list-style-type:lower-alpha">
<li>	Maintain high capacity factors and eliminate or minimize the causes of unscheduled shutdowns and load reductions.
<li>	Adequate maintenance scopes and frequencies to minimize equipment unavailability due to preventive maintenance and unexpected failures.
<li>	Define, recognize, and understand the degradation mechanisms that affect equipment.
<li>	Establish necessary measures to identify degraded equipment or underperforming systems and adopt the appropriate corrective actions, as well as verify their effectiveness before they are incapable of performing their intended function. </li>
</ol>

To achieve these objectives, NPPs need to identify the scope of important components or functions of the plant systems, and design and implement a maintenance program, based on surveillance and monitoring activities. A procedure or guide is needed to establish periodic monitoring and review of the performance of in-scope components. Health reports will be maintained to evaluate the condition of the plant equipment/systems and corrective action will be taken if necessary.

Equipment Reliability takes into account various existing activities related to other programs, including In-Service Inspection, [[US_vs_International_LTO#Maintenance_Rule| Maintenance Rule]], [https://epic.epri.com/EPIC/Inventory#Obsolescence Obsolescence], internal and external Operating Experience, as well as [https://www.wano.info/resources/performance-indicators WANO Indicators] when developing maintenance strategies for plant components/systems.

===Methodology===
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INPO's [https://web.inpo.org/Pages/Equipment-Reliability.aspx AP-913] and WANO's [https://members.wano.org/library/tpm-member-support/wano-guidelines/gl-2018-02-rev-1-equipment-reliability-(1) GL 2018-02] contain an overview of the methodology used in the implementation of an ER process which is summarized by the figure below:

[[File:Subpage-10-Figure-2_reviewed.png|thumb|800 px|center|Equipment Reliability Key Point Diagram]]

The activities necessary to achieve the Equipment Reliability process objectives are summarized in the following points:

#''Scope and reliability analysis:'' Where the identification and selection of critical systems and equipment are assessed for inclusion in the scope of the process. Criticality is based on SSC’s importance for maintaining safety, reliability, and energy generation. 

::To carry out this point, it is convenient to consider those components which are [https://pr.epri.com/PR/SPV/What_is_an_SPV%3F single point vulnerabilities] (SPVs). Just one failure of an [https://pr.epri.com/PR/SPV/What_is_an_SPV%3F SPV] can cause weeks of lost generation and challenge safety system performance as it is described in the [https://pr.epri.com/PR/SPV Single Point Vulnerability Process Guide].
 
::The steps to perform the analysis are the following:
<ol>
<ol style="list-style-type:lower-alpha">
<li>Identification of important functions
<li>Determination of critical component or noncritical SSCs
<li>Controls for component classification changes
<li>Determination of run to maintenance
<li>Document SSCs classification.</li>
</ol>
</ol>

<ol start="2">
<li>''Performance Monitoring:'' This activity is developed on the critical components involved in the important functions of the various systems.
<ol style="list-style-type:lower-alpha">
<li>Establish performance criteria and monitoring parameters. 
<li>Monitoring and trending of each of the parameters and indicators that have been defined in the previous step. For this, EPRI’s [https://pmbd.epri.com/ Preventive Maintenance Basis Database] (PMBD) includes a comprehensive list of failure modes in over 300 components and is essential to determine both the most common failure modes of component types, and their most effective maintenance tasks.
<li>Communicate the performance monitoring results through periodic reports. 
<li>Analyze performance degradation to determine the cause and corrective action according to the corrective action program.</li>
</ol>
<li>''Corrective actions:'' This sub-process can be divided into several phases:
<ol style="list-style-type:lower-alpha">
<li>Causal analysis: To determine failure and corrective actions required to achieve desired performance in accordance with paragraph 3.3.5 of INPO [https://web.inpo.org/Pages/Equipment-Reliability.aspx AP-913].
<li>Evaluate if failure is a Maintenance Rule Functional Failure (MRFF) in accordance with the MR Program.
<li>Prioritization of equipment issues according to their impact on plant operation, plant safety and plant availability. 
<li>Aging and obsolescence considerations.</li>
</ol>
<li>''Continuous ER Improvement:'' The reliability process must be continuously reviewed and challenged looking for the best possible maintenance strategy. Continuous improvement may be carried out as follows:
<ol style="list-style-type:lower-alpha">
<li>Evaluate the need for a change of maintenance task or frequency. 
*Assess whether monitoring criteria or parameters need to be adjusted. 
*Assess the technical basis of the current Preventive Maintenance. 
*Justify and perform Preventive Maintenance change.
<li>Analyze whether there is an applicable Preventive Maintenance template for the type of component being evaluated. There are multiple sources of preventive maintenance recommendations, such as EPRI's [https://pmbd.epri.com/ PMBD], EPRI's [https://lambda.epri.com/ Long-Term Asset Management Basis Design Application] (LAMBDA) or EPRI’s Aging Management Guides.
*Identify whether equipment degradation can be detected. 
*Identifying monitoring parameters or predictive tasks. 
*Determine if there is a preventive maintenance task that can prevent failure. 
*Develop a new maintenance strategy specifying the preventive maintenance tasks most relevant to the reliability of the component. 
*Select preventive maintenance tasks, set frequencies and document the basis for the new maintenance strategy.
<li>Analyze if the failure or consequences of equipment failure can be controlled. 
*Initiate the design change process to eliminate the failure.
*Apply a configuration change or other mitigation strategy to control the component failure. </li>
</ol> 
<li>Long-term management and planning: For each of the equipment included in the scope, an assessment is made and a strategy for its management is defined to ensure safe and reliable operation within the initial life cycle and for Long Term Operation (LTO). [https://lambda.epri.com/ LAMBDA] can be used for long-term management and planning for system and component health and is based on the principles of [https://www.epri.com/research/products/000000000001021188 Integrated Life Cycle Management] (ILCM) including:
<ol style="list-style-type:lower-alpha">
<li>Develop and update the long-term strategy for systems and components identifying and applying the most appropriate maintenance methods for each potential failure. 
<li>Review and integrate various maintenance tasks and schedules established to optimize effort by avoiding redundancy.
<li>Analyze whether the equipment problem meets the [https://www.epri.com/research/products/000000000001021188 ILCM] threshold criteria. 
<li>Clearly define the equipment problem to be solved by the [https://www.epri.com/research/products/000000000001021188 ILCM] process.
<li>Define the risk of failure considering the probability and consequences of failure.
<li>Perform a detailed technical analysis to ensure that the current condition of the equipment problem is fully understood. 
<li>Identify possible solutions to the problem during the detailed technical analysis. 
<li>Perform cost and impact analysis of solution options using tools such as [https://lambda.epri.com/ LAMBDA] and select the best solution based on the result of the assessment.
<li>Generate the Life Cycle Management Plan.
<li>Obtain the approval of the [https://www.epri.com/research/products/000000003002023780 Plant Health Committee] (or equivalent) for the selected solution option. 
<li>Obtain funding approval for the selected solution.
<li>Incorporate the selected solution in the NPP management processes, including priority, status, resources, and schedule.
<li>Implement the approved solution. 
<li>Modify performance monitoring plans and monitor conditions (as required).</li>
</ol>
<li>''Implementation of Preventive Maintenance:'' The process manages the preventive maintenance activities defined in the continuous improvement process and includes the following:
<ol style="list-style-type:lower-alpha">
<li>Organizational approach and project plan for large scale preventive maintenance project revisions to identify the optimal level of preventive maintenance tasks needed to achieve a balance between equipment performance and effective use of resources. 
<li>Establish first-time performance dates for modified or created preventive maintenance programs. 
<li>Develop standard post-maintenance tests. 
<li>Update work management database. 
<li>Develop a model preventive maintenance work order. 
<li>Perform preventive maintenance tasks. 
<li>Document the “as found” condition of the component. Document the degree of degradation observed, indicating whether it is worse than or less than expected so that system, component, or program engineer can adjust the task or frequency accordingly.
<li>Guide to deferring preventive maintenance. If new or updated preventive maintenance processes are not implemented within the timeframe established by the risk assessment, this may increase the probability of a significant equipment failure. </li>
</ol>
</li>
</ol>