ML18180A260

NFPA 805 FAQ 10-0059 - NFPA 805 Monitoring

ML18180A260
Person / Time
Site:	Harris
Issue date:	06/29/2018
From:	Office of Nuclear Reactor Regulation
To:	Shudak T Nebraska Public Power District (NPPD)
Wu A
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ML18180A320	List: ML18180A260 ML18180A319
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Download: ML18180A260 (17)

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FAQ Number 10-0059 FAQ Revision 56 FAQ Title NFPA 805 Monitoring Plant: Harris Nuclear Plant Date:

Contact:

Joelle DeJoseph/ Dave Phone: 919-546-6247479-857-1975402-825-5467 MiskiewiczJessica WalkerTom Shudak Email: joelle.dejoseph@pgnmail.com jwalker@jensenhughes.comtgshuda@nppd.com Distribution: (NEI Internal Use) 805 TF FPWG RATF RIRWG BWROG PWROG Purpose of FAQ:

The purpose of this FAQ is to clarify the following for the NFPA 805 monitoring programMonitoring Program:

Screening criteria Action levels Definition of fire compartments in the fireFire PRA Is this Interpretation of guidance? Yes Proposed new guidance not in NEI 04-02? Yes Details:

NEI 04-02 guidance needing interpretation (include section, paragraph, and line numbers as applicable):

Some clarification is required to help the user implement the monitoring program for NFPA 805.

The clarification stems from lessons learned while developing the monitoring program for the pilot plants.

There are three key points of clarification:

1. Analysis Unit - The monitoring analysis unit used to select high safety significant NFPA 805 fire protection Structures, Systems, and Components (SSCs) should be a fire area. Fire compartments smaller than fire areas may be used instead of fire areas provided the compartments are independent (i.e., share no fire protection SSCs). Selections of nuclear safety capability equipment (NSCA) SSCs that are relied on to meet the nuclear safety performance criteria are done at the plant level using the fireFire PRA. For the purposes of the FAQ, NSCA equipment is intended to include Nuclear Safety Equipment List, Fire PRA equipment, and NPO equipment. The difference in selection scope arises because fire protection SSCs generally respond to fires within the local areas, whereas NSCA SSCs generally respond to fires in many different areas.

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FAQ Number 10-0059 FAQ Revision 56 FAQ Title NFPA 805 Monitoring

2. Screening - Screening can be used to identify the population of SSCs that need not be monitored. The screening of fire protection SSCs may be based on multiple compartments up to and including fire areas. The screening of NSCA SSCs may be based on maintenance ruleMaintenance Rule guidelines used to identify high safety significant SSCs.

3. Action level threshold - When establishing thenew action level thresholdthresholds for reliability and availability, the action level should be no lower thanset to ensure that performance of an SSC at or below the threshold is not indicative of an adverse trend. Action level thresholds for reliability and availability may be set based on Maintenance Rule guidelines used to establish availability and reliability performance criteria for high safety significant SSCs, as informed by the fireFire PRA assumptions. Whenand plant or industry specific information as applicable, a sensitivity study should be performed to determine the margin below the action level that still provides acceptable fire PRA results to help prioritize corrective actions if the action level is reached. .

Circumstances requiring guidance interpretation or new guidance:

Lessons learned.

Detail contentious points if licensee and NRC have not reached consensus on the facts and circumstances:

NoneNFPA 805 inspection activity has identified gaps between industry implementation and NRC interpretations on the use of Maintenance Rule.

Potentially relevant existing FAQ numbers:

None Response Section:

Proposed resolution of FAQ and the basis for the proposal:

See specific revisions listed below.

If appropriate, provide proposed rewording of guidance for inclusion in the next Revision:

See revisions to NEI 04-02 Section 5.2.1, Section 5.2.3, and Appendix E below.

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FAQ Number 10-0059 FAQ Revision 56 FAQ Title NFPA 805 Monitoring 5.2 Monitoring Section 2.6 of NFPA 805 discusses monitoring requirements associated with a risk-informed, performance-based fire protection program. The following are the requirements from Section 2.6:

2-6* Monitoring. A monitoring program shall be established to ensure that the availability and reliability of the fire protection systems and features are maintained and to assess the performance of the fire protection program in meeting the performance criteria. Monitoring shall ensure that the assumptions in the engineering analysis remain valid.

2-6.1 Availability, Reliability, and Performance Levels. Acceptable levels of availability, reliability, and performance shall be established.

2-6.2 Monitoring Availability, Reliability, and Performance. Methods to monitor availability, reliability, and performance shall be established. The methods shall consider the plant operating experience and industry operating experience.

2-6.3 Corrective Action. If the established levels of availability, reliability, or performance are not met, appropriate corrective actions to return to the established levels shall be implemented.

Monitoring shall be continued to ensure that the corrective actions are effective.

Section 2.3 of NFPA 805 provides additional requirements related to assumptions used in performing engineering analyses to support a risk-informed, performance-based fire protection program. The following requirements are included:

2.3 Assumptions. The following assumptions are provided to perform a deterministic analysis of ensuring the nuclear safety performance criteria are met. [Performance-based information (i.e., equipment out of service, equipment failure unrelated to the fire, concurrent design basis events) are integral parts of a PSA and shall be considered when performance-based approaches are utilized.]

Section 2.4.2.1 of NFPA 805 discusses systems and equipment utilized to meet the nuclear safety performance criteria. One requirement cited for those systems and equipment relates to availability and reliability:

2.4.2.1 Nuclear Safety Capability Systems and Equipment SelectionAvailability and reliability of equipment selected shall be evaluated."

Section 2.4.3.3 of NFPA 805 discusses PSA analyses performed to support fire risk evaluations:

2.4.3.3* The PSA approach, methods, and data shall be acceptable to the AHJ. They shall be appropriate for the nature and scope of the change being evaluated, be based on the as-built and as-operated and maintained plant, and reflect the operating experience at the plant.

As part of the transition review, the adequacy of the inspection and testing program to address fire protection systems and equipment within plant inspection and the compensatory measures programs should be reviewed. In addition, the adequacy of the plant corrective action program in determining the causes of equipment and programmatic failures and minimizing their recurrence should also be reviewed as part of the transition to a risk-informed, performance-based licensing basis.

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FAQ Number 10-0059 FAQ Revision 56 FAQ Title NFPA 805 Monitoring 5.2.1 Existing Guidance and Programs The Maintenance Rule (10 CFR 50.65) and Regulatory Guide 1.174 are provided as examples in NFPA 805 Section A.2.6 of acceptable monitoring programs. However,Plants may choose to utilize these existing programs for the NFPA 805 Monitoring Program. Because the appendices of NFPA- 805 are not part of the 10 CFR 50.48(c) rule and flexibility, additional guidance is provided to allow plant-specific processes to be established for performance monitoring if these Maintenance Rule programs are not chosen for the NFPA 805 Monitoring Program.

NEI Document NUMARC 93-01, Industry Guideline for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants, provides an acceptable approach to meet the Maintenance Rule. It includes methods for selecting equipment, establishing and applying risk significance criteria and performance criteria, goal setting and monitoring, assessing and managing risk, performing periodic assessment of performance, and necessary documentation. Although not required, NUMARC 93-01 may be consulted for ideas in developing/updating a monitoring program for fire protection and NSCA SSCs. Due to the efforts expended in complying with the maintenance ruleMaintenance Rule for plant safety systems, a plant may determine that the incremental effort associated with adding selected NSCA SSCs and fire protection program systems and features to previously established programs may be less than establishing a new process or effort. NUMARC 93-01 is very flexible in recognizing the utilization of existing plant programs.

Plant/owner-operator specific initiatives have been undertaken to optimize fire protection surveillance and testing practices and frequencies for fire protection SSCs. This is allowed under traditional regulatory framework using a fire protection standard license condition. Therefore, there are established programs that could be used, enhanced, or modified in an effort to meet the monitoring requirements for fire protection SSCs as discussed in NFPA 805. If a licensee plans to utilize these initiatives post-transition, a discussion should be included in the monitoring section of the LAR and NEI 04-02 Table B-1 Transition of Fundamental Fire Protection Program and Design sections of the LAR. Other entities such as the Department of Defense and Department of Energy have participated in performance-based fire protection inspection and testing efforts. Therefore, there are a number of resources available to establish and maintain a risk-informed, performance-based program.

Acceptable levels of availability, reliability, and performance must be established for both fire protection SSCs and NSCA SSCs. This does not imply or require detailed statistical analysis of all fire protection and NSCA systems, features, components, and sub-components. Instead, determining acceptable levels of availability, reliability, and performance should be commensurate with their risk significance and may be established at the structure, system, or component level, or aggregates of these, where appropriate.

The Maintenance Rule performance criteria for those SSC promoted to or already considered high safety significant in Maintenance Rule can be used as acceptable action level thresholds. The Maintenance Rule requires The use of the Maintenance Rule performance criteria for those items already considered risk significant can be used as acceptable target values. It is up to individual plants to establish plant-specific performance criteria and goals to achieve and criteria for acceptable levels of availability and reliability.

5.2.2 Monitoring Program Development It is expected that a monitoring program for a risk-informed, performance-based fire protection program would be established in phases, with elements added as more of the program relies upon risk-informed, performance-based techniques. It is important to identify parts of the program that may require additional attention during the transition and change evaluation process. Likely candidates would Page 4 of 19

FAQ Number 10-0059 FAQ Revision 56 FAQ Title NFPA 805 Monitoring include monitoring of NSCA equipment or other plant equipment that is not part of the traditional 10 CFR 50, Appendix R post-fire safe shutdown analysis and whose reliability/availability is an important component element of limiting fire risk. Other attributes may include fire protection features that are integral to successful fire modeling in an area, but may not have been considered important in a deterministic approach.

It is expected that a more refined monitoring program (availability, reliability, and performance goals) would be established for the parts of the program where these techniques have been employed. For example, as risk-informed, performance-based techniques are used as part of the change process (i.e.,

fire modeling in a fire area, change in equipment in PRA model, change in equipment relied upon to achieve the nuclear safety performance criteria, change in surveillance frequencies of fire protection equipment), the scope and depth of the monitoring program would need to be adjusted accordingly.

See Appendix E of this document for additional guidance on establishing a monitoring program. This guidance is provided on the four major phases of program development:

Phase 1 - Scoping (fire protection, radioactive release, and NSCA SSCs and programmatic elements)

Phase 2 - Screening Using Risk Criteria Phase 3 - Risk Target Value Determination Phase 4 - Monitoring Implementation 5.2.3 Monitoring Considerations Monitoring programs for fire protection systems and features are not a new concept being introduced as part of a risk-informed, performance-based fire protection program. Surveillance, testing, inspection, and maintenance testing of fire protection systems and features have always been part of a sound program. In addition, the system engineer functions at nuclear power plants have stressed system and equipment health, reliability, and availability.

Risk-informed, performance-based reactor oversight has also increased attention on plant systems and features (including fire protection) with the greatest contribution to risk. Adoption of a risk-informed fire protection licensing basis, however, may introduce some different considerations that may not have been present in a traditional fire protection program.

Calculations and analyses such as fire modeling, particularly a maximum expected and limiting fire scenario, rely on key assumptions that help form the basis for acceptability of configurations and changes to those configurations. These assumptions and input conditions may be different in content and form than previously analyzed.

For example, a fire scenario in a traditional program may have assessed fire hazards by monitoring the combustible loading represented by a BTU/square foot value in an area, which would be monitored by a plant combustible control program. Under a risk-informed, performance-based program, fire modeling, using more advanced and accurate predictions of fire behavior may rely on a certain quantity of oil spill from a pump motor or containment of spilled oil by a retaining berm. The factors that influence results of fire scenarios should be included within an administrative or design control/monitoring program.

Suppression systems, relied upon specifically in a calculation for core damage frequency, have reliability and availability values that will have been used in the calculations. Systems that are Page 5 of 19

FAQ Number 10-0059 FAQ Revision 56 FAQ Title NFPA 805 Monitoring integral to prevention of risk-significant fire scenarios may require monitoring to meet numerical availability numbers in order to satisfy risk acceptance criteria.

Traditional safe shutdown analyses have relied upon safe shutdown equipment (e.g., NSCA SSCs) being in service at the start of a fire. A risk-informed, performance-based approach, particularly in a risk model that calculates core damage frequency, considers both NSCA SSCs and fire protection SSCs reliability and unavailability.

The majority of NSCA SSCs relied upon to ensure post-fire nuclear safety performance criteria is met is equipment that is important for plant risk and mitigation of the consequences of design basis accidents. Therefore, most NSCA equipment important to fire risk will be subjected to inspection, testing, and performance monitoring as part of the Maintenance Rule process and subjected to a variety of plant controls and processes. However, all NSCA equipment important to fire risk may not be part of an existing monitoring program. For example, there may be dominant fire risk contributors that are insignificant contributors to internal events risk. SSCs relied upon to recover from the event may, or may not, be safety significant for the Maintenance Rule. Outliers must be identified and incorporated as necessary into a monitoring program.

If the NSCA equipment and functions are considered High Safety Significant (HSS)/risk significant Maintenance Rule equipment, the plant may choose to use the current Maintenance Rule program in lieu of tracking in a separate NFPA 805 Monitoring Program.

If the NSCA equipment and function are considered in scope of the Maintenance Rule program, but are Low Safety Significant (LSS)/non-risk significant or otherwise do not have defined target values for reliability and availability, then the equipment and functions may be promoted to High Safety Significance in the Maintenance Rule and the plant may use the (updated) Maintenance Rule program in lieu of tracking in a separate NFPA 805 Monitoring Program.

If the NSCA equipment and function are considered out of scope of the Maintenance Rule program, then the equipment and functions may be added as High Safety Significance equipment/functions in the Maintenance Rule and the plant may use the (updated) Maintenance Rule program in lieu of tracking in a separate NFPA 805 Monitoring Program. If the NSCA equipment and function are considered in scope of the Maintenance Rule program, but are Low Safety Significant (LSS)/non-risk significant or otherwise does not have defined target values for reliability and unavailability, then those target values should be developed as part of the NFPA 805 Monitoring Program.

Most of the fire protection features and systems are already being included in the existing fire protection inspection and test program and system/program health programs. The existing program is adequate for routine monitoring of the fire protection systems and features required by the fundamental program of Chapter 3 of NFPA 805 or of low safety significance for Chapter 4 of NFPA 805. The process outlined in Appendix E of this document determines those high safety significant fire protection systems and features, NSCA equipment and programmatic elements that may require additional monitoring beyond normal inspection, testing and surveillance activities.

Due to different success criteria that are evaluated in a risk-informed, performance-based program, other fire protection systems and features may require monitoring. For example, a fire barrier previously not credited for 10 CFR 50, Appendix R compliance may be important to preventing fire from causing a fire-induced loss of offsite power or plant trip, which may prove to be risk significant. Another example is a fire barrier installed prior to efforts for compliance with 10 CFR 50, Appendix R that was abandoned in place without any credit taken for fire protection.

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FAQ Number 10-0059 FAQ Revision 56 FAQ Title NFPA 805 Monitoring This barrier may prove valuable in protecting risk significant circuitry against a credible fire (as determined by fire modeling).

To demonstrate compliance with NFPA 805, action levels should be established for the monitored SSCs, which may be grouped together functionally in pseudo-systems or performance monitoring groups (PMG) to ensure that the assumptions in the engineering analysis remain valid.

Screening compartments and fire areas should also include considerations for Formatted: Indent: Left: 0.5", No bullets or numbering design/operation/maintenance limitations. For instance, fire detection should not subdivide systems beyond the system/train/channel level used in normal operation/maintenance.

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FAQ Number 10-0059 FAQ Revision 56 FAQ Title NFPA 805 Monitoring REPLACE ALL OF APPENDIX E WITH THE FOLLOWING:

E. MONITORING The monitoring process consists of four major phases:

Phase 1 - Scoping Phase 2 - Screening Using Risk Criteria Phase 3 - Risk Target Value Determination Phase 4 - Monitoring Implementation A documented evaluation is used to:

Determine the scope of fire protection, radioactive release, and NSCA SSCs and programmatic elements to monitor.

Establish initial levels of availability, reliability, or other criteria for those elements that require monitoring.

A suggested methodology is outlined below. Figure E-1 provides an overview of the Monitoring Process, while Figure E-2 provides detail on a process for Phases 1 and 2.

Phase 1 - Scoping In order to meet the NFPA 805 requirements for monitoring, the following categories of SSCs and programmatic elements should be included in the NFPA 805 monitoring program:Monitoring Program:

Structures, Systems, and Components required to comply with NFPA 805, specifically:

Fire protection systems and features

- Required by the Nuclear Safety Capability Assessment

- Modeled in the Fire PRA

- Required by Chapter 3 of NFPA 805 Nuclear Safety Capability Assessment equipment*

- Nuclear safety equipment

- Fire PRA equipment

- NPO equipment SSCs relied upon to meet radioactive release criteria Fire Protection Programmatic Elements

• For the purposes of the NFPA 805 Monitoring Program, NSCA equipment is intended to include Nuclear Safety Equipment, Fire PRA equipment, and NPO equipment.

Phase 2 - Screening Using Risk Criteria The equipment from Phase 1 scoping will be screened to determine the appropriate level of NFPA 805 monitoring. As a minimum, the SSCs identified in Phase 1 should be part of an inspection and test program and system/program health program. If not in the current program, the SSCs should be added in order to assure that the criteria can be met reliably.

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FAQ Number 10-0059 FAQ Revision 56 FAQ Title NFPA 805 Monitoring The following screening process is suggested to determine those SSCs that may require additional monitoring beyond normal surveillance activities.

1. Fire Protection Systems and Features Those fire protection systems and features identified in Phase 1 would be candidates for additional monitoring in the NFPA 805 program commensurate with risk significance.

Risk significance may be accomplished at the component, programmatic element, and/or functional level. Since risk is evaluated at the compartment level or fire area level, criteria must be developed to determine those analysis units for which the fire protection SSCs contained within the area are considered risk significant. Screening compartments and fire areas should also include considerations for design/operation/maintenance limitations. For instance, fire detection should not subdivide systems beyond the system/train/channel level used in normal operation/maintenance.

The Fire PRA is the primary tool used to establish the risk significance criteria and performance bounding guidelines. Screening thresholds used to determine risk significant analysis units are those that meet the following criteria:

Risk Achievement Worth (RAW) of the monitored parameter 2.0 (AND) either Core Damage Frequency (CDF) x (RAW) 1.0E-7 per year (OR)

Large Early Release Frequency (LERF) x (RAW) 1.0E-8 per year CDF, LERF, and RAW(monitored parameter) are calculated for each analysis unit fire area. The monitored parameter will be established by licensee at a level commensurate with the amenability of the parameter to risk measurement (e.g., a fire barrier may be more conducive to risk measurement than an individual barrier penetration). If compartments are used that are smaller than fire areas, sufficient basis should be documented.

The monitoring program will include the appropriate fire protection program SSCs based on the criteria above. The licensee may also screen in additional fire protection program SSCs based on plant-specific considerations. Additionally, licensees may submit criteria that are different than above for review and approval in the NFPA 805 LAR.

2. Nuclear Safety Capability Assessment Equipment*

The Fire PRA, in conjunction with the Maintenance Rule criteria, should be used to identify Fire High Safety Significant (FHSS) NSCA SSCs that require monitoring. The Maintenance Rule guidelines differentiating HSS from Low Safety Significant (LSS) SSCs should be used, which may be somewhat different than the criteria used for identifying FHSS fire protection systems and features (e.g., detection and suppression systems) above. This criterion is typically based on RAW, FV, and cutset contribution. The use of the Maintenance Rule screening criteria is appropriate for NSCA equipment because they appear throughout the model and typically do not have Fire Area or Fire Zone dependence. If the Fire PRA and Maintenance Rule are not used to Page 9 of 19

FAQ Number 10-0059 FAQ Revision 56 FAQ Title NFPA 805 Monitoring identify FHSS NSCA SSCs that require monitoring, the licensee should fully describe the process used.

NSCA equipment may already be appropriately monitored by the Maintenance Rule. A comparison of NSCA equipment to the SSCs that are monitored in the Maintenance Rule program should be performed to determine what equipment may require additional NFPA 805 Monitoringmonitoring. For NSCAsNSCA SSC functions currently monitored as HSS or risk significant in Maintenance Rule, monitoring for NFPA 805 can be considered performed by the Maintenance Rule and no further analysis in the monitoring program is needed. For any credited function for the NFPA 805 FHSS NSCA equipment, it should be documented in the Maintenance Rule program that the function is also FHSS for NFPA 805 purposes.

There is adequate justification for using Maintenance Rule performance criteria in meeting the requirements of NFPA 805. The Maintenance Rule criteria is based on the values in the internal events PRA model for unavailability and reliability for SSCs. The Fire PRA is based upon the internal events PRA model and these values have not been changed due to the creation of the Fire PRA. By using the Fire PRA to determine the scope of HSS SSCs, it is ensured that the screening of equipment is based on the impacts on fire risk. Using the performance criteria for risk significance in the Maintenance Rule ensures that the same unavailability and reliability data found in the Fire PRA is utilized. Using the Maintenance Rule criteria also ensures that the requirements of NFPA 805 are met in ensuring that the assumptions in the PRA remain valid.

The performance criteria established in the Maintenance Rule considers the assumptions (i.e.

failure rates and unavailability) assumed in the PRA for the HSS components which are the same failure rates and unavailability used in the Fire PRA. Since the values in the PRA are based upon industry and plant data as collected over specified intervals, the data is indicative of an expected failure or unavailability for an SSC. The PRA may have the mean value listed in the basic event file but the data is based on a distribution that should be considered the core assumption of the PRA. Since the objective of the Maintenance Rule is to identify when an SSC is operating outside of expected parameters, the performance criteria is established to indicate when abnormal conditions exists for the SSC, but it also ensures that the PRA modeling assumptions are considered. In order to meet this expectation, the performance criteria are established at a level which will indicate abnormal operating conditions for the SSC, yet remain within a distribution around the PRA assumptions in order to protect the assumptions in the PRA.

NUMARC 93-01 states the following:

Specific risk significant SSC performance criteria should consider plant-specific performance and, where practical, industrywide operating experience. Performance criteria for risk significant SSCs should be established to assure that reliability and availability assumptions used in the plant-specific PRA, IPE, IPEEE, or other risk determining analysis are maintained or adjusted when determined necessary by the utility.

This is consistent with NFPA 805 which also requires monitoring to consider plant and industry operating experience.

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FAQ Number 10-0059 FAQ Revision 56 FAQ Title NFPA 805 Monitoring 2-6.2 Monitoring Availability, Reliability, and Performance. Methods to monitor availability, reliability, and performance shall be established. The methods shall consider the plant operating experience and industry operating experience.

Maintenance Rule programs at nuclear power plants are reviewed against these criteria and deviations from the ability to meet these standards are documented through condition reports and Maintenance Rule inspections.

Using the Maintenance Rule performance criteria based upon the concept above does several things:

Ensures that the site is monitoring performance criteria that is based upon the assumptions in the PRA Ensures that the site responds when the SSC operates outside the bounds of the PRA assumptions Provides a means for collecting the data for use in adjusting the PRA model as required Ensures that the site appropriately prioritizes resources in relation to system performance For NSCA SSCs not monitored by the Maintenance Rule, the basis for inclusion or exclusion of the SSCs in the NFPA 805 monitoring program should be documented.Maintenance Rule should be documented using site specific Maintenance Rule methodology including performance criteria selection (e.g., expert panel). For any NSCA SSCs not placed in the Maintenance Rule, further NFPA 805 monitoring will be required. FHSS NSCA SSCs not currently monitored in Maintenance Rule as HSS or risk significant should be advanced to the next Phase of the NFPA 805 Monitoring Program in order to develop risk target values.

The fire PRA should be used to identify high-safety-significant (HSS) NSCA SSCs that require monitoring. The Maintenance Rule guidelines differentiating HSS from low-safety-significant (LSS) SSCs should be used. HSS NSCA SSCs not currently monitored in Maintenance Rule should be included in either the Maintenance Rule or the NFPA 805 monitoring program. If the Fire PRA and Maintenance Rule are not used to identify HSS NSCA SSCs that require monitoring, the licensee should fully describe the process used. All NSCA SSCs that are not HSS should be considered LSS and need not be included in the monitoring program.All NSCA SSCs that are not FHSS should be considered Fire LSS and will not be advanced to Phase 3 of the monitoring program.

For fires originating during non-power operational modes, the qualitative use of fire prevention to manage fire risk during Higher Risk Evolutions does not lend itself to quantitative risk measurement. Therefore, fire risk management effectiveness is monitored programmatically similar to combustible material controls and other fire prevention programs. Additional monitoring beyond inspection and test programs and system/program health programs is not considered necessary.

3. SSCs Relied upon for Radioactive Release Criteria The evaluations performed to meet the radioactive release performance criteria are qualitative in nature. The SSCs relied upon to meet the radioactive release performance criteria are not amenable to quantitative risk measurement. Additionally, since 10 CFR Part 20 limits (which Page 11 of 19

FAQ Number 10-0059 FAQ Revision 56 FAQ Title NFPA 805 Monitoring are lower than releases due to core damage and containment breach) for radiological effluents are not being exceeded, equipment relied upon to meet the radioactive release performance criteria is considered inherently low risk. Therefore, additional monitoring beyond inspection and test programs and system/program health programs is not considered necessary.

4. Monitoring of Fire Protection Programmatic Elements Monitoring of programmatic elements is required in order to assess the performance of the fire protection program in meeting the performance criteria. Programmatic aspects include:

Transient Combustible Control; Transient Exclusion Zones Hot Work Control; Administrative Controls Fire Watch Programs; Program compliance and effectiveness Fire Brigade Effectiveness Fire protection health reports, self-assessments, regulator and insurance company reports provide inputs to the monitoring program. The monitoring of programmatic elements and program effectiveness may be performed as part of the management of engineering programs. This monitoring is more qualitative in nature since the programs do not lend themselves to the numerical methods of reliability and availability. These programs form the bases for many of the analytical assumptions used to evaluate compliance with NFPA 805 requirements Phase 3 - Risk Target Value Determination Phase 3 consists of using the Fire PRA, or other processes as appropriate, to determine target values of reliability and availability for the HSSFHSS fire protection/NSCA SSCs and programmatic elements established in Phase 2 as requiring additional monitoring beyond inspection and test programs and system/program health programs.

Reliability and availability risk target values are established by an expert panel. The values are based on an evaluation of relevant industry and plant-specific historical performance data deemed to represent a period of acceptable performance and effective maintenance. The values should be consistent with the assumed level of performance in the supporting analyses.

The risk target values should not in general be set equal to the long term average values in the (fire) PRA. It is important to set the risk target values at a level high enough above the long term average to avoid a high false alarm rate and low enough to detect potential low level adverse trends in unreliability or unavailability that warrant investigating maintenance improvements.

Risk target values are established for the SSCs at the component level, program level, or functionally through the use of the pseudo system or performance monitoring group concept.

The expert panel should consider the risk significance in the Fire PRA of long term operation at the risk target values in the determination of the risk target values. This consideration should include the use of a core damage frequency (CDF) sensitivity to ensure that risk target values established to trigger performance improvement efforts do not result in unacceptable risk as it pertains to NFPA 805 engineering conclusions.

The site-specific Maintenance Rule monitoring methodology including performance criteria selection (e.g., expert panel) may be used for any FHSS SSCs.

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FAQ Number 10-0059 FAQ Revision 56 FAQ Title NFPA 805 Monitoring For FHSS NSCA SSCs and functions considered High Safety Significant (HSS)/risk significant in Maintenance Rule, the plant may use the current Maintenance Rule program in lieu of tracking in a separate NFPA 805 Monitoring Program.

For FHSS NSCA SSCs and functions considered in scope of the Maintenance Rule program, but are Low Safety Significant (LSS)/non-risk significant in Maintenance Rule or otherwise do not have defined target values for reliability and availability, then the equipment and functions may be promoted to High Safety Significance in the Maintenance Rule and the plant may use the (updated) Maintenance Rule program in lieu of tracking in a separate NFPA 805 Monitoring Program.

For FHSS SSCs and functions considered out of scope of the Maintenance Rule program, then the equipment and functions may be added as High Safety Significance equipment/functions in the Maintenance Rule and the plant may use the (updated) Maintenance Rule program in lieu of tracking in a separate NFPA 805 Monitoring Program.

Should a plant choose to rely on the Maintenance Rule program for NFPA 805 monitoring, those SSCs that are only in MR due to NFPA 805 monitoring requirements (i.e., those SSCs though do not meet MR scoping criteria) will not be subject to the requirements of 10 CFR 50.65, paragraphs (a)(1), (a)(2) or (a)(3). Performance that exceeds the established risk target value(s) for an SSC within the NFPA 805 Monitoring Program would be entered into the station corrective action program for resolution.

As discussed above, monitoring like Maintenance Rule is a risk informed process that may not specifically mirror the values in the Fire PRA. The actual action level should be informed by the value in the Fire PRA model and determined based on expert panel or evaluation using plant and industry experience.

The unavailability and reliability values in the Fire PRA are based on representative data over a length of time. The mean value is used in the Fire PRA. Therefore, the actual target values may differ from the mean value reflected in the Fire PRA to avoid normal performance from exceeding target values (i.e. False exceedance due to expected fluctuations above and below an average value). Risk sensitivity or other statistical methods should be utilized to ensure the established target values, which differ from the Fire PRA, do not result in unacceptable risk as it pertains to NFPA 805 engineering conclusions.

The NFPA 805 Monitoring Program risk target values should be documented. For FHSS SSCs Formatted: Body Text and functions that rely on the Maintenance Rule program, it should be documented in the Maintenance Rule program that the SSCs and functions are FHSS for NFPA 805 purposes. Any FHSS SSCs not placed in the Maintenance Rule, will required separate NFPA 805 risk target value determination and monitoring.

Adverse trends and unacceptable levels of availability, reliability, and performance will be reviewed against established action levels. The NFPA 805 Monitoring Program failure criteria and action level targets should be documented.

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FAQ Number 10-0059 FAQ Revision 56 FAQ Title NFPA 805 Monitoring Phase 4 - Monitoring Implementation Phase 4 is the implementation of the monitoring program, once the monitoring scope and criteria are established. Monitoring should consist of periodically gathering, trending, and evaluating information pertinent to the performance, and/or availability of the SSCs and comparing the results with the established goals and performance criteria to verify that the goals are being met.

Results of monitoring activities should be analyzed in timely manner to assure that appropriate action is taken. The corrective action process will be used to address performance of fire protection and nuclear safety SSCs that do not meet performance criteria.

For fire protection and NSCA SSCs that are monitored, unacceptable under the NFPA 805 Monitoring Program, levels of availability, (if monitored), reliability, and performance will be reviewed against the established action levels. If an action level is triggered, corrective actiona condition report should be initiated to identify the negative trend. A corrective action plan willshould then be developed using the appropriate licensee process. Once the plan has been implemented, improved performance should return the SSC back to below the established action level.

Over time, as data is gathered for the Fire PRA models, it is expected the action levels set in Phase 3 should be re-evaluated and updated as necessary. The Fire PRA is expected to monitor the as-built, as-operated plant, which will cause Test and Maintenance and Reliability values to be updated to match the plant performance.

The Risk Target Values should be set based on the assumption that a component may impact the overall risk model. These action levels may, over time, not be bounded by the plant Fire PRA specific values that are updated based on plant performance, but instead represent levels that would bound the overall risk model. This is consistent with the process used in Maintenance Rule and is in line with ensuring the overall assumptions of the analysis are met.

A periodic assessment should be performed (e.g., at a frequency of approximately every two to three operating cycles), taking into account, where practical, industry wide operating experience.

This may be conducted as part of other established assessment activities. Issues that should be addressed include:

Review systems with performance criteria. Do performance criteria still effectively monitor the functions of the system? Do the criteria still monitor the effectiveness of the fire protection and nuclear safety capability assessment systems?

Have the supporting analyses been revised such that the performance criteria are no longer applicable or new fire protection and nuclear safety capability assessment SSCs, programmatic elements and/ or functions need to be in scope?

Based on the performance during the assessment period, are there any trends in system performance that should be addressed that are not being addressed?

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FAQ Number 10-0059 FAQ Revision 56 FAQ Title NFPA 805 Monitoring Determine scope of SSCs and Phase 1 Programmatic Elements Scoping to Monitor Establish risk significance See Figure E-2 for criteria Detail Phase 2 Screening Using Risk Criteria Establish list of HSS Fire and NSCA SSCs (for each PMG) based on Criteria Establish Functional Failure criteria and Action Levels for each PMG Phase 3 Risk Target Value Determination Establish reliability and availability criteria for each PMG SSCs in preventive Is performance maintenance & condition acceptable? Yes monitoring program No Address performance via corrective action process Perform appropriate maintenance on SSCs Is new SSC level goal required?

No Is performance Yes acceptable?

Yes No Establish goals Phase 4 Monitoring Address performance via Implementation corrective action process Monitor performance goals Is new SSC level No goal required?

Is goal met?

Yes Yes No Address performance via corrective action process Is new SSC level goal required?

Yes No Figure E NFPA 805 Monitoring Process Page 15 of 19

FAQ Number 10-0059 FAQ Revision 56 FAQ Title NFPA 805 Monitoring Commented [TS1]: SW - Should this have an item that says in MR as HSS, then follow Maintenance Rule?

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FAQ Number 10-0059 FAQ Revision 56 FAQ Title NFPA 805 Monitoring Field Code Changed Figure E NFPA 805 Monitoring - Scoping and Screening Page 17 of 19

FAQ Number 10-0059 FAQ Revision 56 FAQ Title NFPA 805 Monitoring Appendix A Formatted: Font: 14 pt, Bold Formatted: Font: 14 pt The following are examples of each of the flow paths that are documented in Figure E-2. Formatted: Normal, Centered Formatted: Normal EXAMPLE 1: The use of Maintenance Rule Program in the areas of NFPA 805 monitoring of Formatted: Indent: Left: 0" unavailability. Formatted: Font: Bold Each licensee may have a unique method of implementing the Maintenance Rule. Other risk sensitivity or statistical evaluation methods similar to those utilized for Maintenance Rule may be used with the Fire PRA to demonstrate acceptability of target values. This example represents just one method for using the existing Maintenance Rule for monitoring a HSS component that is included in the NFPA 805 monitoring Program.

The High Pressure Coolant Injection (HPCI) system is credited in the NSCA and Fire PRA.

Therefore, HPCI is included in the NFPA 805 monitoring program scope.

HPCI is also part of the plant maintenance rule monitoring program. Therefore, NFPA 805 Formatted: Normal, No bullets or numbering, Tab stops:

0", Left monitoring of HPCI is incorporated into the maintenance rule program.

Formatted: Normal, No bullets or numbering The maintenance rule program unavailability performance criterion for HPCI was reassessed Formatted: Normal, No bullets or numbering, Tab stops:

using the fire PRA to ensure consistency with fire PRA assumptions. 0", Left The fire PRA was directly applied to ensure consistency of the maintenance rule performance criteria with the fire PRA. Exceeding the thresholds of unavailability established directly results in entry into the Licensees corrective action program to allow resolution and return of performance to acceptable unavailability levels.

Furthermore, the application of the fire PRA when establishing unavailability performance criteria included use of core damage frequency (CDF) sensitivity to ensure that thresholds established to require performance improvement did not result in unacceptable risk as it pertains to NFPA 805 engineering conclusions. Fire PRA sensitivity evaluations were applied to validate that the temporary exceedance of an unavailability threshold resulted in very small increases in CDF that would not invalidate performance based inputs provided through engineering analysis.

In general, these sensitivity evaluations used a change in fire CDF metric of 1.0E-06/yr for assessment of the unavailability performance criteria. This metric was used in the maintenance rule in absence of defined and specific guidance. This metric ensures effective monitoring by:

• Ensuring that the temporary increase in CDF is very small. Regulatory Guide 1.174 recognizes the 1.0E-06 metric as a threshold of acceptability based on the very small increase in CDF.

• Ensuring that actions are taken within the Licensee corrective action program to return performance below the unavailability threshold. The threshold ensures action is taken at Page 18 of 19

FAQ Number 10-0059 FAQ Revision 56 FAQ Title NFPA 805 Monitoring a very low risk level to ensure performance of the fire protection program is maintained over the life of the plant Formatted: Font: 12 pt Through implementation of NFPA 805 endorsed guidance the licensee monitoring program Formatted: Normal, No bullets or numbering, Tab stops:

0", Left provides a process that maintains acceptable performance of the fire protection program. Steps taken to use the fire PRA as a direct input while incorporating maintenance rule performance criteria for unavailability provides the fire PRA consistency required for monitoring adequacy and compliance to NFPA 805 monitoring requirements.

EXAMPLE 2: Fire Protection System NFPA Monitoring Process Formatted: Font: Bold The Preaction Automatic Sprinkler System in the Cable Spreading Room is credited in the Fire Formatted: Tab stops: 0", Left PRA. Therefore, it is included in the NFPA 805 monitoring program scope.

A risk screening was applied to the Cable Spreading Room Preaction System and the Risk Achievement Worth (RAW) value is greater the 2.0 and the CDF x RAW is >1.0E-7 per year.

Therefore, it is classified as a Fire High Safety Significant System (FHSS).

The Fire PRA was used to determine the Availability and Reliability of the system used 95.60%.

A FHSS Pseudo System was developed for the Preaction Automatic Sprinkler system.

Performance Monitoring Groups (PMG) were developed for the Pseudo System. Action levels were determined for each of the PMGs. The cumulative action levels for the PMGs are set to ensure that the actual probability of success (1 - probability of failure) of the pseudo-system is not less than the value assumed in the FPRA. For each PMG, there are two action levels set: (1) allowable unavailable PMG hours AND (2) allowable PMG failures.

Action levels were set for the number of allowable failures (reliability) and allowable out of service hours (availability) to ensure that the FPRA remains valid. For each pseudo system, the availability and reliability were taken from the FPRA Model and multiplied together to determine the Availability and Reliability used in developing the action levels.

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