ML19212A723

04_02_Fire HRA Training Overview of Fire HRA

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NRC-RES/EPRI FIRE PRA METHODOLOGY:

Task 12 - Fire HRA Fire HRA Training Overview NRC-RES Fire PRA Workshop Module IV August 5-9, 2019 Rockville, MD

Course Overview

1. Introduction to HRA

2. Overview of the EPRI/NRC Fire HRA Guidelines

3. Identification and definition of fire human failure events

4. Qualitative analysis

5. Fire HRA Application Experience

6. Quantitative analysis a) Screening b) Scoping c) Detailed EPRI approach & ATHEANA (detailed)

7. Recovery analysis

8. Dependency analysis

9. Uncertainty analysis Fire HRA Overview Slide 2 Fire PRA Workshop 2019, Rockville, MD

EPRI/NRC Fire HRA Guidelines Overview Purpose of the Fire HRA training course module Training objectives Background on the Fire HRA Guidelines Fire HRA development team, approach & timeline Fire HRA Guidelines, public review & path forward Summary of EPRI/NRC Fire HRA Guidelines scope & contents Fire HRA Overview Slide 3 Fire PRA Workshop 2019, Rockville, MD

EPRI/NRC Fire HRA Guidelines Purpose of Training Course Provide training on guidance from EPRI/NRC Fire HRA Guidelines (NUREG-1921/EPRI 1023001)

Opportunity for face-to-face, real-time interactions between authors and potential future users Opportunity to improve training

-It is important for us to get student/audience feedback for future presentations Fire HRA Overview Slide 4 Fire PRA Workshop 2019, Rockville, MD

Fire HRA Module Training Objectives 1:Be able to name the steps in the process for conducting a Fire HRA.

2:Be able to list the different categories of fire HRA human failure events.

3:Demonstrate a knowledge of ASME/ANS PRA Standard high level requirements related to HRA.

4:Be able to identify context and performance shaping factors used in the analysis of fire human failure events.

5:Be able to list the quantification methods available for HEPs.

6:Understand the concept and importance of addressing dependencies between fire HRA events.

Fire HRA Overview Slide 5 Fire PRA Workshop 2019, Rockville, MD

Background on the Issue of Fire HRA Almost 50% of USA plants transitioning to NFPA-805

- Using NUREG/CR-6850 [EPRI 1011989] for the Fire PRA Guidance NUREG/CR-6850 [EPRI 1011989] addresses:

- Identifying human failure events (HFEs)

- Assigning conservative screening human error probabilities (HEPs)

- Fire performance shaping factor (PSF) information NUREG/CR-6850 [EPRI 1011989] does not:

- Describe a methodology for developing best-estimate HEPs (given fire related effects)

- Address the requirements of:

ASME/ANS RA-Sa-2009, Addenda to ASME/ANS RA-S-2008, Standard for Level 1 / Large Early Release Frequency Probabilistic Risk Assessment for Nuclear Power Plant Applications, Chapter 4 for fires Consequently, there was a need for fire-specific guidance for best-estimate HRA quantification in fire PRA Fire HRA Overview Slide 6 Fire PRA Workshop 2019, Rockville, MD

EPRI/NRC Fire HRA Guidelines High Level Objectives Through joint NRC and industry efforts, address the need for HRA guidance, especially for best-estimate quantification, for use in fire PRAs Address methodology Address guidance for implementing the methodology Develop a joint EPRI/NRC report (similar to NUREG/CR-6850 [EPRI 1011989])

Consider ASME/ANS PRA Standard requirements and user needs Fire HRA Overview Slide 7 Fire PRA Workshop 2019, Rockville, MD

EPRI/NRC Fire HRA Guidelines Development Team EPRI NRC Stuart Lewis Susan Cooper & Kendra Hill EPRI Project Manager NRC-RES Project Manager EPRI RES Jeff Julius (Lead) Susan Cooper (Lead)

Jan Grobbelaar & Kaydee Kohlhepp John Forester Erin Collins Stacey Hendrickson & Mary Presley Independent Review Team NRC Reps Utility HRA Reps Fire HRA Overview Slide 8 Fire PRA Workshop 2019, Rockville, MD

Fire HRA Guidelines Development Approach

1) Review of Generic Fire Literature and Data Existing guidance & literature Historical & experiential plant fire data

2) Fire HRA Methodology & Guidelines Development Examined HRA process & identified how process and tasks would change for the fire environment and accident response scenarios in response to a fire

3) Fire HRA Review & Test NRC and industry peer review team (7 people)

Two plants tested Scoping method flowcharts Fire HRA Overview Slide 9 Fire PRA Workshop 2019, Rockville, MD

Evolution of the Fire HRA Guidelines Plant Peer NRC Draft for Final Review review public comment July Response 2012

& FPRA of 1st comment resolution Draft Review Public Comment response Technical revision review &

comment & report Editing initial draft revision revision Comb.

First PRA Industry 805 LAR Final Kick-Off Draft Std Peer Rvw Submittals Rpt 2007 2008 2009 2010 2011 2012 ACRS PRA Fire HRA Sub-committee Course Testing at Pilot by ACRS PRA Sub.,

BWR/PWR PWROG then Full Committee Application of Fire HRA Guidelines to FPRA at Non-Pilot Plants Fire HRA Overview Slide 10 Fire PRA Workshop 2019, Rockville, MD

Fire HRA Guidelines Public Review & Comment NUREG-1921/EPRI 1019196 issued in November 2009 for public review and comment Prior to public review period, obtained comments during presentation to ACRS PRA Subcommittee Received 265 public comments (~75 editorial) from:

- PWROG - EPRI HRA Users Group

- BWROG - Exelon Final report was revised to address public comments, etc.

- Approach is not fundamentally different, but

- Some important changes (e.g., reduced requirements for assessing feasibility of operator actions during screening and scoping analyses)

Fire HRA Overview Slide 11 Fire PRA Workshop 2019, Rockville, MD

Fire HRA Guidelines Path Forward Final Guidelines document issued July 2012 It is anticipated that this guidance will be used by the industry as part of transition to NFPA 805 and possibly in response to other regulatory issues This is the first report addressing fire-related HRA for fire PRA that goes beyond the screening level As the methodology is applied at a wide variety of plants, the document may benefit from future improvements to better support industry-wide issues being addressed by fire PRA Fire HRA Overview Slide 12 Fire PRA Workshop 2019, Rockville, MD

Fire HRA Guidelines Summary Objectives and Scope Identify/analyze existing post-initiator HFEs

- Changes to previously modeled HFEs due to fire effects Identify/analyze post-initiator fire response HFEs

- New category of HFE to be analyzed Procedures, training, cues typically different from existing post-initiator HFEs

- Includes alternative shutdown (such as MCR abandonment due to habitability or transferring command and control to outside the MCR)

Identify/analyze post-initiator HFEs in response to spurious actuations and indications

- New category of HFE to be analyzed Fire HRA Overview Slide 13 Fire PRA Workshop 2019, Rockville, MD

Fire HRA Guidelines Summary Objectives and Scope (continued)

Implement post-initiator fire HEPs in fire PRA model(s)

- Initial quantification using screening or scoping approach

- Identification of risk significant events for later detailed HRA (e.g.,

to meet ASME/ANS Part 2 supporting requirement HR-G1, Capability Category II)

- Including dependency analysis Out of Scope

- Pre-initiators (per NUREG/CR-6850 [EPRI 1011989])

- Fire brigade response (except for impacts on fire PSFs)

Fire HRA Overview Slide 14 Fire PRA Workshop 2019, Rockville, MD

Fire HRA Guideline Summary Standard HRA process used for Fire HRA modeling:

- Based on other processes and guidance ASME/ANS PRA Standard NUREG-1792 Fire Manual Actions, NUREG-1852 SHARP1 ATHEANA Overall, NUREG-1921 [EPRI-1023001] captures the state-of-practice in HRA then advances the state-of-the-art for fire-specific PRA purposes Fire HRA Overview Slide 15 Fire PRA Workshop 2019, Rockville, MD

Fire HRA Process Steps

1. Identification & definition of human failure events (HFEs):

Substantial guidance provided, including feasibility test Feasibility Evaluation (Go / No-Go) example criteria

- Sufficient time available to complete action

- Procedures & cues exist

- Sufficient manpower

2. Qualitative analysis Iterative process that continues throughout quantification steps Discussion includes tips & tools for information collection, &

interpretation, addressing important fire-specific topics, etc.

Comprehensive discussion of HFE feasibility under fire conditions As fire PRA develops, fire HRA must consider additional fire scenario-specific details that become available Fire HRA Overview Slide 16 Fire PRA Workshop 2019, Rockville, MD

Fire HRA Process Steps (continued)

3. Quantification Methods - three levels Screening Quantification

- Refinement/relaxation for areas identified in NUREG/CR-6850 [EPRI 1011989] implementation

- Typically used in NUREG/CR-6850, Task 7 first/screening quantification Scoping Fire HRA method added (new):

- Developed to address the majority of HFEs, thereby conserving HRA resources

- Simplified HRA quantification method with limited set of performance shaping factors (PSFs) to address

- Decision tree format (enhancing traceability)

- Typically used during NUREG/CR-6850, Tasks 7 or 8, or early quantification of detailed fire scenarios in Tasks 11/14 Fire HRA Overview Slide 17 Fire PRA Workshop 2019, Rockville, MD

Fire HRA Process Steps (continued)

3. Quantification (contd, 3rd of 3 methods)

Detailed Fire HRA

- Uses existing methods

- Performance shaping factors modified for the fire context:

EPRI Cause-Based Decision Tree & HCR/ORE; &

THERP NRCs ATHEANA HRA method

- Typically used in NUREG/CR-6850 [EPRI 1011989]

Tasks 11/14 quantification of detailed fire scenarios as needed Fire HRA Overview Slide 18 Fire PRA Workshop 2019, Rockville, MD

Fire HRA Process Steps (continued)

4. Recovery, Dependency, and Uncertainty

- Typically part of NUREG/CR-6850 [EPRI 1011989] Tasks 11/14 quantification of detailed fire scenarios

- In general, these tasks are not different than that for internal events PRA

- NUREG-1921 [EPRI 1023001] discusses fire-specific aspects of these tasks Fire HRA Overview Slide 19 Fire PRA Workshop 2019, Rockville, MD

Steps in the Fire HRA Process Recovery Analysis Identification Qualitative Quantitative Dependency and Analysis Analysis Analysis Definition Screening Scoping Uncertainty Detailed analysis Analysis Fire HRA Overview Slide 20 Fire PRA Workshop 2019, Rockville, MD

Mapping Fire HRA Process to Fire PRA Tasks NUREG/CR-6850 Fire HRA Process Step

[EPRI 1011989] Task Task 2 - Component Identification of previously existing HFEs &

Selection potential response to spurious Task 5 - Fire-Induced Identification and Definition of fire Risk Model response HFEs Task 12 - Fire HRA Qualitative Analysis - context &

performance shaping factors Task 7 - First/Screening Quantification - typically screening or Quant. scoping Task 8 - Scoping Quantification - typically scoping Quantification Tasks 11/14 - Detailed Quantification & Dependency Scenario Quantification could be screening, scoping or detailed HRA Task 15 - Uncertainty Uncertainty Fire HRA Overview Slide 21 Fire PRA Workshop 2019, Rockville, MD

Fire HRA Guideline Summary NUREG-1921 [EPRI 1023001] also provides some additional tools & discussion that may be helpful to the analysis, e.g.,

- Section 2.3, Relationship to Other Fire PRA tasks More detailed discussion of relationship between HRA and fire PRA Table 2-1 relates NUREG/CR-6850 tasks to ASME/ANS PRA Standard elements & HRA tasks

- Section 2.5, Fire-Induced Cable Failure(s) and Electrical Faults Discussion of how fire PRA treats fire-induced cable failure(s)

Table 2-2 relates different types of fire damage to different fire PRA tasks & how this damage is addressed Fire HRA Overview Slide 22 Fire PRA Workshop 2019, Rockville, MD

Fire HRA Guideline Summary NUREG-1921 [EPRI 1023001] also provides some additional tools and discussion (continued)

- Section 4.3, Feasibility Assessment Feasibility is defined & criteria are identified Discussion of how feasibility assessments can be performed

- Section 4.6.2, Timing Discussion of timing windows used in NUREG-1921 [EPRI 1023001] quantification methods Discussion of how to develop timing information

- Section 4.11, Reviews with Plant Operations Discussion on how to conduct talk-throughs & walk-throughs Fire HRA Overview Slide 23 Fire PRA Workshop 2019, Rockville, MD

Fire HRA Technical Overview Fire HRA Process Summary:

- Identification and Definition

- Qualitative Analysis

- Quantification Methods:

Screening Scoping Detailed

- Recovery, Dependency, & Uncertainty Each Fire HRA process step is further described in subsequent presentations Fire HRA Overview Slide 24 Fire PRA Workshop 2019, Rockville, MD

Questions?

Fire HRA Overview Slide 25 Fire PRA Workshop 2019, Rockville, MD