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- Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request
- Acceptance, Acceptance, Acceptance, Acceptance
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MONTHYEARML0725500632007-08-30030 August 2007 NFPA 805 Transition Pilot Plant FAQ 06-0019, Revision 2 Project stage: Request ML0730605502007-09-0707 September 2007 NFPA 805 Transition Pilot Plant FAQ 07-0040 Project stage: Request ML0727402622007-09-20020 September 2007 NFPA-805 Transition Pilot Plant FAQ 07-0038 Project stage: Request ML0727402682007-09-20020 September 2007 NFPA-805 Transition Pilot Plant FAQ 07-0039 Project stage: Request ML0727402482007-09-20020 September 2007 NFPA-805 Transition Pilot Plant FAQ 06-0011, Revision 2 Project stage: Request ML0726104552007-09-24024 September 2007 NFPA 805 Observation Visit Trip Report Project stage: Request ML0727402552007-09-28028 September 2007 NFPA-805 Transition Pilot Plant FAQ 06-0019, Revision 3 Project stage: Request ML0735500232007-11-12012 November 2007 NFPA 805 Transition Pilot Plant FAQ 07-0033, Revision 1 Project stage: Request ML0735100822007-11-12012 November 2007 NFPA 805 Transition Pilot Plant FAQ 06-0025, Revision 3 (Corrected Version) Project stage: Request ML0733200282007-11-26026 November 2007 NFPA 805 Transition Pilot Plant FAQ 06-0012, Revision 5, Determining Manual Actions That Require a Change Evaluation During Transition. 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License Amendment Request (LAR) No. 2008-01 Project stage: Request ML0816901212008-06-17017 June 2008 Forthcoming Closed Meeting with Progress Energy Carolinas, Inc., to Discuss the May 29, 2008, License Amendment Request (LAR) to Transition the Shearon Harris Nuclear Plant, Unit 1 (Harris) to National Fire Protection Association (Nfpa).. Project stage: Meeting ML0818901932008-06-30030 June 2008 Completion Schedule for Part 2 of License Amendment Request to Adopt NFPA 805 Performance-Based Standard for Fire Protection for Light Water Reactor Generating Plants (2001) Edition, License Amendment Request No. 2008-01 Project stage: Request ML0818406962008-07-0707 July 2008 Meeting with Progress Energy Carolinas, Inc. and Duke Energy Carolinas, LLC, to Discuss the 05/29&30/2008, License Amendment Requests to Transition Shearon Harris, Unit 1, and Oconee, Units 1, 2, & 3 to NFPA Standard 805 Project stage: Meeting ML0818905292008-07-11011 July 2008 Summary of Closed Meeting with Progress Energy Carolinas Regarding May 29, 2008, License Amendment Request to Transition the Shearon Harris Nuclear Plant Unit 1, to National Fire Protection Association Standard 805, Performance-Based.... Project stage: Meeting ML0820703912008-07-17017 July 2008 Meeting Handouts from 7/17/08 Public Meeting on the Harris and Oconee LARs to Transition to NFPA-805 Project stage: Meeting ML0820605362008-08-0707 August 2008 Summary of Mtg. with Progress Energy Carolinas, and Duke Energy Carolinas to Discuss the LARs to Transition the Shearon Harris and Oconee Nuclear Plants to National Fire Protection Association Standard NFPA-805 Project stage: Acceptance Review ML0827011582008-09-26026 September 2008 Acceptance Review Regarding the License Amendment Request to Transition to NFPA 805, Performance-Based Standard for Fire Protection for Light Water Reactor Generating Plants. Project stage: Acceptance Review ML0828700162008-09-26026 September 2008 Nc Warn'S Response to Board Notification - Enclosure P-1 - Shearon Harris Nuclear Power Plant, Unit 1 - Acceptance Review NFPA-805 License Amendment Request, September 26, 2008 Project stage: Request ML0828804552008-09-30030 September 2008 Preliminary Oconee LAR Acceptance Review Matrix Project stage: Acceptance Review ML0828902592008-10-16016 October 2008 and 10/08/2008 - Summary of Conference Calls with Duke Energy Carolinas to Discuss the Acceptance Review of the May 30, 2008, License Amendment Request (LAR) to Adopt National Fire Protection Association (NFPA) 805 for Oconee Project stage: Acceptance Review ML0830900742008-11-12012 November 2008 Summary of Category 2 Public Meeting Held to Discuss National Fire Protection Association Standard 805 Pilot Plant Process: Current Lessons Learned from the Pilot License Amendment Request Reviews (TAC Nos. MD8807, MD8832, MD8833, & MD8834) Project stage: Meeting HNP-08-113, Supplement to Request for License Amendment, to Adopt NFPA 805 Performance-Based Standards for Fire Protection for Light Water Reactor Generating Plants (2001 Edition)2008-11-14014 November 2008 Supplement to Request for License Amendment, to Adopt NFPA 805 Performance-Based Standards for Fire Protection for Light Water Reactor Generating Plants (2001 Edition) Project stage: Supplement ML0829601532008-11-17017 November 2008 Summary of Meeting with Progress Energy Carolinas, Inc., to Discuss Shearon Harris Unit 1 National Fire Protection Association Standard 805 License Amendment Request Project stage: Meeting HNP-08-121, Supplement 2 to Request for License Amendment to Adopt NFPA 805 Performance-based Standard for Fire Protection for Light Water Reactor Generating Plants (2001 Edition)2008-12-11011 December 2008 Supplement 2 to Request for License Amendment to Adopt NFPA 805 Performance-based Standard for Fire Protection for Light Water Reactor Generating Plants (2001 Edition) Project stage: Supplement ML0903000302009-01-30030 January 2009 Acceptance Review Regarding Amendment to Adopt National Fire Protection Association 805 Performance-Based Standard for Fire Protection for Light Water Reactor Generating Plants, 2001 Edition Project stage: Acceptance Review ML0903304962009-02-0202 February 2009 Acceptance Review of License Amendment Request to Adopt the National Fire Protection Association Standard No. 805, Performance-Based Standard for Fire Protection for Light Water Reactor Electric Generating Plants,.. Project stage: Acceptance Review ML0902903272009-03-10010 March 2009 Regulatory Audit in Support of the License Amendment Request to Implement a Risk-Informed, Performance-Based Fire Protection Program as Allowed by Title 10 of the Code of Federal Regulations, Paragraph 50.48(c) Fire Protection Project stage: Other ML0909900182009-04-10010 April 2009 04/21-22/2009, Notice of Meeting with Progress Energy Carolinas, Inc., and Duke Energy Carolinas, LLC, to Discuss Topics Involving the License Amendment Requests to Transition the Shearon, Unit 1 and the Oconee, Units 1, 2 and 3 Project stage: Meeting ML0916002812009-06-11011 June 2009 Notice of Consideration of Issuance of Amendment to Facility Operating License and Opportunity for a Hearing Project stage: Other ML0921707152009-08-0606 August 2009 Request for Additional Information Regarding Amendment to Adopt National Fire Protection Association Standard 805 (NFPA 805), Performance-Based Standard for Fire Protection for Light Water Reactor ... Project stage: RAI HNP-09-084, Response to Request for Additional Information Regarding License Amendment Request to Adopt National Fire Protection Association Standard 805, Performance-based Standard for Fire Protection for Light Water Generating Plants.2009-08-13013 August 2009 Response to Request for Additional Information Regarding License Amendment Request to Adopt National Fire Protection Association Standard 805, Performance-based Standard for Fire Protection for Light Water Generating Plants. Project stage: Response to RAI HNP-09-086, Second Response to Request for Additional Information Regarding License Amendment Request to Adopt National Fire Protection Association Standard 805, Performance-based Standard for Fire Protection for Light Water Reactor...2009-08-28028 August 2009 Second Response to Request for Additional Information Regarding License Amendment Request to Adopt National Fire Protection Association Standard 805, Performance-based Standard for Fire Protection for Light Water Reactor... Project stage: Response to RAI HNP-09-094, Third Response to Request for Additional Information License Amendment Request to Adopt National Fire Protection Association Standard 805, Performance-Based Standard for Fire Protection for Light Water Reactor....2009-10-0909 October 2009 Third Response to Request for Additional Information License Amendment Request to Adopt National Fire Protection Association Standard 805, Performance-Based Standard for Fire Protection for Light Water Reactor.... Project stage: Response to RAI HNP-09-096, Additional Information Re License Amendment Request to Adopt National Fire Protection Association Standard 805, Performance-Based Standard for Fire Protection for Light Water Reactor Generating Plants2009-12-16016 December 2009 Additional Information Re License Amendment Request to Adopt National Fire Protection Association Standard 805, Performance-Based Standard for Fire Protection for Light Water Reactor Generating Plants Project stage: Request ML1001302542010-01-14014 January 2010 Second Request for Additional Information Regarding the License Amendment Request to Adopt National Fire Protection Association Standard 805, Performance-Based Standard for Fire Protection for Light Water Reactor Generating Plant Project stage: RAI HNP-10-008, Response to Second Request for Additional Information Regarding License Amendment Request to Anfp Association Standard 805, Performance-Based Standard for Fire Protection for Light Water Reactor Generating Plants.2010-02-0404 February 2010 Response to Second Request for Additional Information Regarding License Amendment Request to Anfp Association Standard 805, Performance-Based Standard for Fire Protection for Light Water Reactor Generating Plants. Project stage: Request ML1006009872010-03-0909 March 2010 Discussion of Clarification Questions Related to the License Amendment Request to Adopt National Fire Protection Association Standard 805, Performance - Based Standard for Fire Protection for Light ... Project stage: Other HNP-10-040, Response to 3rd Round of RAI License Amendment Request to Adopt National Fire Protection Association Standard 805, Performance-Based Standard for Fire Protection for Light Water Reactor Generating Plants.2010-04-0505 April 2010 Response to 3rd Round of RAI License Amendment Request to Adopt National Fire Protection Association Standard 805, Performance-Based Standard for Fire Protection for Light Water Reactor Generating Plants. Project stage: Request HNP-10-064, Additional Items Related to License Amendment Request to Adopt National Fire Protection Association Standard 805, Performance-Based Standard for Fire Protection for LWR Generating Plants.2010-06-0909 June 2010 Additional Items Related to License Amendment Request to Adopt National Fire Protection Association Standard 805, Performance-Based Standard for Fire Protection for LWR Generating Plants. Project stage: Request 2008-06-17
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MONTHYEARML22314A0752022-11-10010 November 2022 2B - Exam Administrative Items - Normal Release ML22034A3992022-02-16016 February 2022 Enclosure 1 - IP 71130.03 Cy 2021 - IR 8 Baseline Inspection Completion ML22034A3952022-02-16016 February 2022 Enclosure 3 - IP 96001 CY2021 - IR 8 Baseline Inspection Completion ML22034A3972022-02-16016 February 2022 Enclosure 2 - IP 92707 CY2021 - IR 8 Baseline Inspection Completion ML18338A0882018-12-0404 December 2018 Attachment FormerFAQResponses_11302018 ML18180A2602018-06-29029 June 2018 NFPA 805 FAQ 10-0059 - NFPA 805 Monitoring ML18073A3582018-03-15015 March 2018 NRC Staff Comments FAQ 18-0015 ML17235B1482017-08-23023 August 2017 U.S. Nuclear Regulatory Commission - Tornado Missile Risk Evaluator (TMRE) Methodology Topics and Methodology Feedback ML16315A2892016-11-10010 November 2016 Attachment 5 EPRI RETRAN-3D Computer Code Manuals, NP-7450(A) RA-16-003, Attachment 5 EPRI RETRAN-3D Computer Code Manuals, NP-7450(A)2016-11-10010 November 2016 Attachment 5 EPRI RETRAN-3D Computer Code Manuals, NP-7450(A) ML18039A8562016-06-0202 June 2016 Fpra FAQ 16-0011 - Cable Tray Ignition - Draft ML14191B2622014-07-10010 July 2014 NFPA 805 Transition FAQ 14-0070, Revision 0 ML13170A3282013-06-13013 June 2013 Special Inspection Question & Answers ML1214300352012-05-21021 May 2012 NFPA 805 Transition FAQ 12-0062, Revision 1 ML12056A0522012-03-12012 March 2012 Enclosure 6 - List of Power Reactor Licensees and Holders of Construction Permits in Active or Deferred Status ML1204105892012-02-10010 February 2012 NFPA 805 Transition FAQ 10-0059, Revision 5 ML1204105852012-02-10010 February 2012 NRC Staff Response to NFPA 805 Transition FAQ 10-0059, Revision 4 ML1203201932012-02-0101 February 2012 NFPA 805 Transition FAQ 10-0059, Revision 4 ML1202603842012-01-13013 January 2012 FAQ Revision NFPA 805 Monitoring ML1201903132012-01-13013 January 2012 NFPA 805 Transition FAQ 10-0059, Rev 3 ML1202603722012-01-13013 January 2012 NFPA 805 Monitoring ML1202604252012-01-13013 January 2012 FAQ-1 - NFPA 805 Monitoring ML1202604402012-01-13013 January 2012 FAQ - NFPA 805 Monitoring ML1128600532011-09-30030 September 2011 NRC Staff Comments on FAQ 59R2 ML1127304102011-09-30030 September 2011 NRC Staff Response to NFPA 805 Transition FAQ 10-0059, Revision 2 RA-11-025, Enclosure 1, Attachment 2 - Duke Energy Corporation and Progress Energy, Inc. Organization Charts Post Merger2011-09-0202 September 2011 Enclosure 1, Attachment 2 - Duke Energy Corporation and Progress Energy, Inc. Organization Charts Post Merger ML1123401522011-08-19019 August 2011 NFPA 805 Transition FAQ 10-0059, Rev 2 ML1111804812011-04-21021 April 2011 NFPA 805 Transition FAQ 10-0059, Rev 1 ML1109105082011-03-31031 March 2011 NRC Staff Response to NFPA 805 Transition FAQ 10-0059, Revision 0 (Part 2) ML0933507512010-01-14014 January 2010 Temporary Instruction 2515/180, Managing Fatigue ML0916101892009-06-0303 June 2009 NFPA 805 Transition Pilot Plant FAQ 07-0035, Revision 2, Bus Duct Counting Guidance for High Energy Arcing Faults ML0909905112009-04-29029 April 2009 Enclosure 1: Shearon Harris Regulatory Audit Participants ML1020301612009-04-12012 April 2009 Tritium Concern Talking Points ML1019402162009-04-12012 April 2009 Offsite Notification to State/Local Agencies Regarding Tritium Release Onsite - EN 44951 ML0909305002009-04-0303 April 2009 Afpb Staff Response to NFPA 805 Transition Pilot Plant FAQ 07-0035, Revision 1 ML1020301722009-04-0101 April 2009 Tritium Questions and Answers ML0908500122009-03-26026 March 2009 NFPA 805 Transition Pilot Plant FAQ 07-0035, Revision 1, Bus Duct Counting Guidance for High Energy Arching Faults ML0902902182009-01-22022 January 2009 NFPA 805 Transition Pilot Plant FAQ 07-0030 ML1019402762008-12-0202 December 2008 Nuclear Condition Report for Tritium in Groundwater NEI 04-02, NFPA 805 Transition Pilot Plant FAQ 07-0039, Revision 2, Lessons Learned - NEI 04-02 B-2 Table2008-09-12012 September 2008 NFPA 805 Transition Pilot Plant FAQ 07-0039, Revision 2, Lessons Learned - NEI 04-02 B-2 Table ML0825904662008-09-12012 September 2008 NFPA 805 Transition Pilot Plant FAQ 07-0039, Revision 2, Lessons Learned - NEI 04-02 B-2 Table ML0914201382008-09-0909 September 2008 NFPA 805 Transition Pilot Plant FAQ 07-0039, Revision 2 - Clean Version ML0821000342008-07-24024 July 2008 NFPA 805 Transition Pilot Plant FAQ 07-0038, Revision 1 ML0813006972008-05-0909 May 2008 NFPA 805 Transition Pilot Plant FAQ 07-0032, Revision 2 ML0809101362008-03-28028 March 2008 NFPA 805 Transition Pilot Plant FAQ 07-0039, Revision 1, Lessons Learned - NEI 04-02 B-2 and B-3 Tables ML0807004112008-03-10010 March 2008 NFPA 805 Transition Pilot Plant FAQ 07-0032, Revision 1, Clarification of 10 CFR 50.48(c), 50.48(a), and GDC 3. ML0807001572008-03-10010 March 2008 NFPA 805 Transition Pilot Plant FAQ 06-0025, Revision 5 ML0806704192008-03-0707 March 2008 CDBI Findings ML0735500252007-12-20020 December 2007 NFPA 805 Transition Pilot Plant FAQ 07-0036, Revision 1 ML0735500212007-12-20020 December 2007 NFPA 805 Transition Pilot Plant FAQ 06-0025, Revision 4 2022-02-16
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FAQ Number 07-0038 FAQ Revision 0 FAQ Title Lessons learned on Multiple Spurious Operations Page 1 of 8 faq 07-0038 mso lessons learned rev 0.doc Plant: Harris Date:September 20, 2007 Contact: Keith Began Phone:(919) 546-5026 Email:Keith.Began@pgnmail.com Distribution: (NEI Internal Use) 805 TF FPWG RATF RIRWG BWROG PWROG Purpose of FAQ:
The purpose of this FAQ is to provide updates to NEI 04-02 to reflect lessons learned from pilot plant activities, NFPA 805 task force meetings, and NRC reviews and
discussions on multiple spurious operations (MSOs).
Is this Interpretation of guidance? Yes / No Proposed new guidance not in NEI 04-02? Yes / No Details: NEI 04-02 guidance needing interpretation (include section, paragraph, and line numbers as applicable):
NEI 04-02 Section Appendix B.2, Transition of Nuclear Safety Performance Criteria.
A separate FAQ will be developed to addr ess the impact on the post transition change process (Appendices I and J of NEI 04-02)
Circumstances requiring guidance interpretation or new guidance:
Lessons have been learned from pilot plant activities, NFPA 805 task force meetings, and NRC reviews and discussions on multiple spurious operations (MSOs).
Detail contentious points if licensee and NRC have not reached consensus on the facts and circumstances:
None.
Potentially relevant existing FAQ numbers:
FAQ Number 07-0038 FAQ Revision 0 FAQ Title Lessons learned on Multiple Spurious Operations Page 2 of 8 faq 07-0038 mso lessons learned rev 0.doc Response Section:
Proposed resolution of FAQ and the basis for the proposal:
See the proposed attached proposed NEI 04-02 markups.
If appropriate, provide proposed rewording of guidance for inclusion in the next Revision:
See the proposed attached proposed NEI 04-02 markups.
FAQ Number 07-0038 FAQ Revision 0 FAQ Title Lessons learned on Multiple Spurious Operations Page 3 of 8 faq 07-0038 mso lessons learned rev 0.doc B.2.1.3 Fire-Induced Circuit Failur es (Multiple Spurious Operations)
A licensee should may choose to submit a summary of its licensing basis on circuits for NRC review and approval. At a minimum, the summary should must contain sufficient information relevant to methods, tools, and acceptance criteria used to enable the staff to determine the acceptability of the licensee's methodology. The NRC staff may request additional information necessary to adequately assess the licensee's submittal.
The options to establish a licensing basis incl ude 1) crediting a well documented design basis which meets minimum NRC expectations, or 2) using other methods accepted by the AHJ for selection of circuits and for using risk
-insights to evaluate the consequences.
Minimum NRC expectations include (however are not limited to) addressing single spurious and risk significant multiple spurious failures, DID and SM.
The NRC staff has reviewed Revision 1 of NEI 00-01 and concluded that Chapter 3 provides an acceptable deterministic approach way for analysis of post-fire safe shutdown circuits (Reference RIS 2005-30 and Regulatory Guide 1.205) to select circuits.
, and Chapter 4 provides an acceptable way to determine risk
- sig nificance of circuit findings.
In addition, an acceptable Fire PRA as defined in Regulatory Guide 1.205 Section C.4.3 includes methods for the selection of cables and detailed circuit failure modes analysis, as well as the integration of these circuit failures into the overall Fire PRA (e.g., NUREG/CR-6850 Tasks 3, 9, 10, and 14).
In addition, the NRC staff has reviewed the following methodology provided by Duke Energy and agrees that it provides an acce ptable approach for screening out non
-risk-significant issues
.
The approach outlined in Figure XX below is one acceptable method to address fire-induced multiple spurious operations. This method uses insights from a Fire PRA that meets the requirements of Regulatory Guide 1.205, Revision 0.
This process is intended to be in support of tr ansition to a new licensing basis. Post-transition changes would use the risk-informed, performan ce-based change process. The post-transition change process for the assessment of a specific MSO would be a simplif ied version of this process, and may not need the level of detail shown in the following section (e.g., An expert panel may not be necessary to identify and asse ss a new potential MSO. Identification of new potential MSOs may be part of the plant cha nge review process and/
or inspection process).
FAQ Number 07-0038 FAQ Revision 0 FAQ Title Lessons learned on Multiple Spurious Operations Page 4 of 8 faq 07-0038 mso lessons learned rev 0.doc Figure XX - Multiple Spurious Operations - Transition Resolution Process
FAQ Number 07-0038 FAQ Revision 0 FAQ Title Lessons learned on Multiple Spurious Operations Page 5 of 8 faq 07-0038 mso lessons learned rev 0.doc Step 1 - Identify potential MSOs of concern. Information sources that may be used as input include: Post-fire safe shutdown analysis (NEI 00-01, Revision 1, Chapter 3)
Generic lists of MSOs (e.g., from Owners Groups, if available.)
Self assessment results (e.g., NEI 04-06 assessments performed to addressed RIS 2004-
- 03) PRA insights (e.g., NEI 00-01 Revision 1, Appendix F)
Step 2 - Conduct an expert panel to assess pl ant specific vulnerabilities (e.g., per NEI 00-01, Rev. 1 Section F.4.2). The expert panel should focus on system and component interactions that could impact nuclear safety. This information will be used in later tasks to identify cables and potential locations where vulnerabilities could exist.
[Note: The physical location of the cables of concern (e.g., fire zone/area routing of the identified MSO cables), if known, may be used at th is step in the process to focus the scope of the detailed review in further steps.]
Step 3 - Update the fire PRA model to include the MSOs of concern.
This includes the:
Identification of equipment (NUREG/CR-6850 Task 2)
Identification of cables that, if damaged by fire, could result in the spurious operation (NUREG/CR-6850 Task 3, Task 9)
Identify routing of the cables identified above.
Step 4 - Identify the risk significance of MSOs of concern.
This step is intended to identify MSOs that cont ribute to risk significant scenarios. Simplifying approaches may be used to 'quantify' the risk of the MSO. For example, the estimate of fire risk (CDF) may be assumed to be all associated with the MSO, and therefore serve as a surrogate measure for CDF associated with the MSO. The us e of surrogates (e.g., CDF for all of the scenarios within a fire area) provides a more definitive measure of risk for a fire in an area, would simplify long term configuration management of MSO assessment, and allows resources to be focused on refining and addressing issues (including issues being associated with MSOs) that are risk significant.
Determine if the risk significance of the MSO warrants additional review
/ action. The following table and figure provide a summar y of risk thresholds that have been reviewed and found acceptable by the NRC for addressing MSOs. If surrogate approaches are used to focus on higher risk scenarios, a CDF value of 1E-08/yr prior to operator respons e to address the fire-induced spurious operation (LERF value of 1E-09/y r) should be used as a threshold value for the scenarios, consistent with the values for MSOs previously found to be acceptable. Refer to Table XX and Figure YY.
FAQ Number 07-0038 FAQ Revision 0 FAQ Title Lessons learned on Multiple Spurious Operations Page 6 of 8 faq 07-0038 mso lessons learned rev 0.doc Cables that are part of the combination in the 'gray area' are included in the NSCA for disposition using the same tools as other cables in the NSCA per a later step in the process. Cables may be conservatively incl uded based on surrogate risk indicators such as significance of a single cable at a time or all 'spurious' cables (c ables that can cause a sp urious operation due to a hot short) included in a fire scenario/initiator are included in the NSCA.
Table XX - MSO Risk Assessment Criteria Ref. CDF LERF Characterization Action NEI 04-02 (B.2.1) & RG 1.205 (C.3.3) < 1E-08/yr (prior to operator response*)
< 1E-09/yr (prior to operator response*)
Not potentially risk significant Band 1 on Figure YY. No further consideration required (document results)
NEI 04-02 (B.2.1) & RG 1.205 (C.3.3) <1E-06/yr (prior to operator response*) but 1E-08/yr <1E-07/yr (prior to operator response*) but 1E-09/yr "Gray Area" Band 2 on Figure YY Evaluate and include as part of NSCA ("design change or procedure change put in place, if possible, Procedure actions still meet feasibility criteria but are not considered 'required'."
NEI 04-02 (B.2.1) >1E-06/yr (prior to operator response*)
>1E-07/yr (prior to operator response*)
Potentially risk significant Band 3 on Figure YY Evaluate and include as part of NSCA * "Operator response" refers to operator manual action in response to the fire-induced spurious operation(s).
Figure YY - NEI 04-02 Section B.2.1 Change in Ri sk Criteria due to MSOs (Change in CDF Only Shown)
FAQ Number 07-0038 FAQ Revision 0 FAQ Title Lessons learned on Multiple Spurious Operations Page 7 of 8 faq 07-0038 mso lessons learned rev 0.doc Table YY - MSO Risk Assessment Criteria Ref. CDF LERF Characterization Action RG 1.205 (C.3.3 and C.3.1) <1E-06/yr but 1E-07/yr <1E-07/yr but 1E-08/yr Post transition See Figure ZZ Post-transition - Process in accordance with FP license condition (RG 1.205 - C.3.1)
Allows risk increase to consider credit for feasible & reliable recovery actions. Figure ZZ - RG 1.205 Change in Risk Criteria due to MSOs (Change in CDF Only Shown)
Potential MSOs of concern below the screening threshold (band 1 of Figure YY) do not require further evaluation. The review that was performed should be documented for configuration control. This documentation should include a disposition of items recommended by the expert panel for additional review.
Step 5 - Evaluate in the Nuclear Safety Capability Assessment (NSCA)
Include the equipment/cables of concern in the Nuclear Safety Capability Assessment (NSCA) for additional assessment on a fire area-by-fire area basis.
Step 6 - Evaluate for Compliance For MSOs of concern that have been included in the NSCA for additional assessment, determine if the concern can be addressed by meeting the pre-transition licensing basis (e.g., deterministic separation/protection per 10 CFR 50, Appendi x R / NUREG-0800 with consideration of approved exemptions, etc.).
MSOs that meet the separation/protection requirements of the pre-transition licensing basis should be documented and the appropriate transition documentation updated as necessary.
FAQ Number 07-0038 FAQ Revision 0 FAQ Title Lessons learned on Multiple Spurious Operations Page 8 of 8 faq 07-0038 mso lessons learned rev 0.doc Step 7 - Resolution Options Risk significant MSOs that do not meet the separation/protection re quirements of the pre-transition licensing basis will be reviewed for other resolution options, such as:
Process as a risk-informed, performance-based change evaluation.
Perform plant modifications to meet deterministic or risk-informed, performance-based acceptance criteria.
Perform procedure changes