ML19114A466
| ML19114A466 | |
| Person / Time | |
|---|---|
| Issue date: | 04/25/2019 |
| From: | Shivani Mehta NRC/NRR/DRA |
| To: | Casto G NRC/NRR/DRA |
| Mehta S | |
| References | |
| Download: ML19114A466 (5) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 April 25, 2019 MEMORANDUM TO: Greg Casto, Chief PRA Licensing Branch B Division of Risk Assessment Office of Nuclear Reactor Regulation FROM: Shivani Mehta, Engineer /RA/
PRA Licensing Branch B Division of Risk Assessment Office of Nuclear Reactor Regulation
SUBJECT:
SUMMARY
OF THE APRIL 3, 2019, CATEGORY 2 PUBLIC MEETING ON NATIONAL FIRE PROTECTION ASSOCIATION STANDARD 805 FIRE PROBABILISTIC RISK ASSESSMENT - FIRE REALISM WORKSHOP On April 3, 2019, the U.S. Nuclear Regulatory Commission (NRC) staff held a public workshop with industry stakeholders and the public regarding existing National Fire Protection Association (NFPA) 805 and fire probabilistic risk assessment (PRA) frequently asked questions (FAQs) and research projects.
The agenda included the discussion of the following four existing FAQs:
- FPRA FAQ-18-0014: Time to Detection is Zero for the Start of Manual Non-Suppression Probability Calculations
- FPRA FAQ-18-0017: Conditional Trip Probability for Modeling Operator Discretion
- FPRA FAQ-18-0018: Updated Non-Suppression Probability
- FPRA FAQ-18-0019: Transient Fire Heat Release Rate Curves
Enclosure:
List of Meeting Attendees CONTACT: Shivani Mehta, NRR/DRA 301-415-0860
G. Casto 2 The industry indicated that FAQ 18-0017 (ADAMS Accession Number ML18180A303) and FAQ 18-0019 (ML18271A106) will be withdrawn. FAQ 18-0019 replaced FAQ 18-0015 (ML18277A208), and FAQ 18-0019 will be subsumed into an existing joint NRC/EPRI research program.
For FPRA FAQ 18-0014, the industry provided an updated version at the meeting (ML19101A352). NRC staff and industry discussed the relationship between the future publication of the draft joint NRC/EPRI report, NUREG-2230 (EPRI 3002016051), Methodology for Modeling Fire Growth and Suppression Response of Electrical Cabinet Fires in Nuclear Power Plants (ML19087A215). Industrys intention is to revise this FAQ to address ignition sources beyond electrical cabinets and continue discussing it within the FAQ program. As a result, industry requested that NRC comment on this latest version. The industry indicated it will wait for NUREG-2230 to be complete before assessing the changes necessary for this FAQ in order to align the FAQ with the research program. NUREG-2230 is expected to be released for public comment in mid-2019. The industry and NRC discussed means to enhance the efficiency of achieving closure of this issue should it continue as a FAQ. Another draft joint NRC/EPRI report, NUREG-2178 Vol. 2 (EPRI 3002016052), Refining and Characterizing Heat Release Rates from Electrical Enclosures During Fire, was identified that contributes to fire PRA realism and is expected to be released for public comment in mid-2019 also. During this meeting, the status of each of these joint NRC/EPRI reports was corrected from draft for public comment to draft working copies.
For FPRA FAQ 18-0018 the industry provided an updated version at the meeting (ML19101A341). The NRC staff and industry discussed the data and methodology for developing the non-suppression probabilities in the FAQ. The staff indicated that the approach in the FAQ to develop non-suppression probabilities is not consistent with NUREG-2169 (EPRI 3002002936), Nuclear Power Plant Fire Ignition Frequency and Non-Suppression Probability Estimation Using the Updated Fire Events Database, which includes the latest collection of fire events data and development of non-suppression probabilities and ignition frequencies. As a part of the discussion on the proper path with this FAQ, the NRC and EPRI will determine the schedule for updating the data and the resulting non-suppression probabilities and ignition frequencies in a revision to NUREG 2169. Both the industry and NRC agreed to think further about the proper path forward for this issue Industry indicated that no new FAQs would be submitted to the NRC staff for review, and as such, would consider retirement of the fire PRA FAQ program following disposition of the remaining FAQs (18-0014 and 18-0018). The staff agreed to consider retiring the FAQ program. The NRC staff and industry will remain engaged on the two remaining FAQs discussed above (or determine a suitable alternate path for FPRA FAQ 18-0018).
The industry brought forward questions on the endorsement of Nuclear Energy Institute (NEI) 00-01 Guidance for Post-Fire Safe Shutdown Circuit Analysis, and NEI 04-02 Guidance for Implementing a Risk-Informed, Performance-Based Fire Protection Program Under 10 CFR 50.48(c).
The Industry inquired as to the status of review of NEI 00-01 and NEI 04-02 by NRC staff. The NRC staff stated that they plan to provide final comments on the most recent versions received from NEI by the end of June of 2019, with the updated draft regulatory guides entering the publication process in late 2019. Endorsement of these NEI documents will occur through the final issuance of the updated regulatory guides. Further, the NRC plans to document its interim
G. Casto 3 acceptance of the new technical information contained in NEI 00-01, which was previously published in NRC NUREG reports, while the regulatory guides are being processed.
Industry provided an update on a project for developing additional PRA credit for Very Early Warning Fire Detection Systems (VEWFDS) (ML19095B580). Industry stated that a team met at the Shearon Harris Nuclear Power Plant the week of November 12, 2018. The industry intends to develop a revised event tree for calculating non-suppression probability for VEWFDS.
NEI will publish a report on the revised methodology for public information once they have completed the work.
Industry informed the meeting participants that it is undertaking two initiatives. The first is on a License Amendment Request (LAR) template. This template is intended to aide licensees in submitting LARs specifically related to NFPA 805 c.2.vii compliance for performance-based methods with regard to nuclear safety goals, defense-in-depth, and safety margins. The second is to pursue changing the delta CDF and delta LERF requirements for self-approval in license conditions with respect to NFPA 805.
Although the industry intends to submit no new FPRA FAQs, it also suggested that the staff and industry remain engaged on new FPRA methods and approaches through continued periodic public meetings. The staff agreed that continued engagement would be beneficial, and agreed to support periodic meetings.
As a Category 2 meeting, the public was invited to participate in the meeting by discussing regulatory issues with the NRC staff at designated points identified on the agenda. There were no public comments provided.
ML19114A466 Office NRR/DRA/APLB NRR/DRA/APLB NRR/DRA/APLB Name SMehta JHyslop Gcasto J Robinson for Date 04/18 /2019 04 / 25 /2019 04 / 25 / 2019 National Fire Protection Association (NFPA) 805/ FIRE Probabilistic Risk Assessment (PRA) - Fire Realism Workshop: LIST OF MEETING ATTENDEES April 3, 2019 U.S. Nuclear Regulatory Commission Staff Greg Casto Susan Cooper Russell Felts Michael Franovich JS Hyslop Shivani Mehta Nicolas Melly Brian Metzger Charles Moulton David Stroup Gabriel Taylor Industry Stakeholders Victoria Anderson (Nuclear Energy Institute)
Jana Bergman (Curtiss Wright)
Mary Anne Billings (STPNOC)
Rob Cavedo (Exelon)
Joelle DeJoseph (Jensen Hughes)
Jeff Ertman (Duke Energy)
Michael Fletcher (Ameren - Callaway Plant)
Jason Floyd (Jensen Hughes)
Mark Hulet (APS)
Young Jo (Southern Nuclear Company)
Francisco Joglar (Jensen Hughes)
Vicken Khatchadourian (Engineering Planning and Management (EPM), Inc.)
Elizabeth Kleinsorg (Jensen Hughes)
Gregory Kvamme (Xcel Energy)
James Lechner (Jensen Hughes)
Jack Lemmer (Duke Energy)
Ashley Lindeman (Electric Power Research Institute)
Chaqing Lioa (Tennessee Valley Authority)
Sandy Naccarato (Southern Nuclear Company)
Victor Ontiveros (Jensen Hughes)
Faramarz Pournia (Southern Nuclear Company)
Chris Pragman (Exelon)
Andy Ratchford (Jensen Hughes)
Frederick Ross (Tennessee Valley Authority)
Mark Schairer (Engineering Planning and Management (EPM), Inc.)
Denis Shumaker (PSEG)
Tracy A. St. Clair (First Energy)
Richard J Strmple (First Energy)
Kieth Vincent (NextEra)
Ashton Williams (Entergy ANO)
Tyler Clayton Wolfford (Tennessee Valley Authority)
Fatma Yilmaz (STPNOC)
Kiang Zee (Jensen Hughes)
Members of the Public Fleurdeliza De Peralta (PNNL)
Jongseuk ENCLOSURE