ML25029A118
| ML25029A118 | |
| Person / Time | |
|---|---|
| Issue date: | 01/29/2025 |
| From: | Jesse Seymour NRC/NRR/DRO/IOLB |
| To: | |
| References | |
| Download: ML25029A118 (1) | |
Text
2025 Power Plant Simulator Conference NRC Update Presented by Jesse Seymour Sr. Reactor Engineer (Examiner)
Operator Licensing and Human Factors Branch January 29, 2025
NRC Update on Current Topics of Interest Disclaimer: the contents of this presentation do not necessarily indicate the Nuclear Regulatory Commissions views.
Agenda
- Endorsement of ANS-3.5-2018 / Draft Regulatory Guide 1.149 (Rev. 5)
- ANS-3.5 Use Considerations
- Proposed 10 CFR Part 53 Rulemaking Status
- Industry performance trends
- Questions
ANS-3.5-2018 Endorsement &
RG 1.149 Considerations
- Endorsement of ANS-3.5-2018 via Draft Regulatory Guide (RG) 1.149 Rev. 5 is ongoing with current Part 55 wording as basis o Endorsement had been paused due to other rulemaking activities to avoid multiple revisions of RG 1.149; decision made recently to move forward due to length of delay
- NRC staff development work on draft RG 1.149 Rev. 5 includes endorsement of ANS-3.5-2018, but other areas that the staff are considering clarifying may also include:
o Addressing partial scope/part-task simulators o Guidance for Commission-approved simulators (CAS) o Core load modeling at multi-unit SMR facilities
- The revised RG 1.149 will have a public comment period
- Technical lead for document is Bernie Litkett o Bernard.Litkett@nrc.gov
ANS-3.5 Use Considerations Most power reactor facilities are committed to ANSI/ANS-3.5-2009 (as endorsed by Rev. 4 of RG-1.149); some remain on older versions of ANS-3.5 though (e.g., 1985 and 1998)
Besides operator training and licensing, simulators are relied upon for facility licensing actions, such as performance-based testing to support human factors engineering (HFE) analyses, staffing validations, and overall adequacy of a new (or modified) design NUREG-0711 (NRC HFE review model) provides criteria for HFE testbeds; one approach to meeting these is meeting ANS-3.5-2009 New simulators declared as plant referenced simulators are inspected with inspection procedure 41502 (refers to ANSI/ANS-3.5)
Commission-approved simulators (CAS) also need to account for adequate performance testing; the Vogtle CAS safety evaluation referenced the ANS-3.5 standard as well
Proposed 10 CFR Part 53 Rulemaking
- The proposed Part 53 includes a new framework for staffing, operator licensing, human factors engineering, and training
- Includes simulation facility requirements for licensed operator training and examination programs; key aspects are:
- Incorporates improvements based upon lessons learned
- Would allow that a reference plant may not be constructed
- Full-scope simulators are not mandated; partial scope simulators may be acceptable if adequate to meet needs
- Provides a flexible simulation facility definition for compatibility with plants having limited on-site facilities
- Prior to initial fuel load, simulator models would be allowed to replicate the intended initial core loads
Part 53 Rulemaking (contd)
- Current status of the proposed Part 53 is available via:
https://www.nrc.gov/reading-rm/doc-collections/rulemaking-ruleforum/active/ruledetails.html?id=1108
- Public comments are currently being accepted via:
https://www.regulations.gov/docket/NRC-2019-0062
- As mentioned, Part 53 includes the potential use of alternative simulation facilities (e.g., part task simulators or even the plant itself) if requirements are met:
o However, it is not the NRCs intention to allow initiation of transients on the actual plant for these purposes o Rather, use of the actual plant for training and examination purposes is envisioned to be restricted to techniques including, in part, simulated tasks, use of augmented reality technology, and similar approaches that provide value while avoiding operation of plant components
2024 Performance Trends
- Overall trend of simulator programs continues to be good with no recent inspection findings related to 55.46
- Examination reports have documented some minor issues
- 2024 PWR observations (gathered from exams at 3 facilities) o Failure of the simulator to not load saved trigger events resulted in the applicant crew tripping the reactor due to the conditions presented by the simulator software o A hardware issue caused multiple controllers to spike randomly, resulting in multiple rounds of troubleshooting and the need for examiner workarounds during exam o Computerized Procedures System crashed, resulting in a temporary loss of the ability for operators to access the plant procedures
2024 Performance (contd)
- 2024 BWR observations (gathered from exams at 4 facilities) o Simulator issues during an exam included a breaker spuriously tripping, plant computer display and control board pump indication mismatch, Reptile crash during a scenario, and Core Model dropping out during a scenario o Simulator issues during another exam included intermittent rod insert/withdraw blocks, loss of cooling water not affecting recirculation pump temperatures, a diesel run light not staying on during the cooldown period, and a feedwater pump continuing to run without suction o Flow indication being present on a Standby Gas Treatment System exhaust flow recorder that should have had none o A pull-to-lock switch slipping back out of position
Questions?
Jesse Seymour Jesse.Seymour@nrc.gov