ML23272A192
| ML23272A192 | |
| Person / Time | |
|---|---|
| Site: | 99902049 |
| Issue date: | 06/20/2023 |
| From: | Hayes M NRC/NRR/DNRL/NLIB |
| To: | Brenner A Holtec, SMR |
| References | |
| EPID L-2023-LRO-0053 | |
| Download: ML23272A192 (5) | |
Text
Enclosure U.S NUCLEAR REGULATORY COMMISSION FEEDBACK REGARDING SMR, LLC (A HOLTEC INTERNATIONAL COMPANY) WHITE PAPER ON HUMAN FACTORS ENGINEERING FUNCTIONAL REQUIREMENTS ANALYSIS AND FUNCTION ALLOCATION FOR CHEMICAL AND VOLUME CONTROL SYSTEM (EPID L-2023-LRO-0053)
SPONSOR INFORMATION Sponsor:
SMR, LLC (A Holtec International Company)
Sponsor Address:
Krishna P. Singh Technology Campus 1 Holtec Blvd.
Camden, NJ 08104 Docket/Project No(s).:
99902049 DOCUMENT INFORMATION Submittal Date: June 20, 2023 Submittal Agencywide Documents Access and Management System (ADAMS) Accession No. ML23165A086 Purpose the White Paper: SMR (Holtec) describes the purpose of this document, Report No.
HI-2210328, Rev. 0, Functional Requirements Analysis and Function Allocation for Chemical and Volume Control System, is to document the results of the functional requirements analysis and function allocation for the operation of the chemical and volume control system.
Action Requested: Based on the June 20, 2023, public meeting discussion regarding the SMR-160 human factors engineering (HFE) program (ML23216A133), SMR (Holtec) requested NRC feedback and observations on the information discussed in the Hl-2210328 document and associated proprietary documents provided as Enclosures 1 through 7 to the submittal letter (ML23165A081). These are listed at the end of this document under the REFERENCES heading.
NOTE: The material referenced contains proprietary information.
FEEDBACK AND OBSERVATIONS The feedback and observations in this White Paper and associated references listed below are preliminary and subject to change. (See REFERENCES at end of this document). The feedback and observations are not regulatory findings on any specific licensing matter and are not official agency positions.
Feedback and Observations NUREG-0711, Human Factors Engineering Program Review Model, Revision 3, Chapter 4, Functional Requirements Analysis and Function Allocation, provides the NRC staff review guidance for the functional requirements analysis (FRA) and function allocation (FA) portion of an applicants HFE program and processes. This chapter describes that an applicant should provide either an Implementation Plan (IP), describing the methodology for conducting the FRA and FA, that is later followed by a completed Results Summary Report (RSR) or, alternatively, just the completed RSR itself (which would also be expected to include a description of the methodology used). In general, an RSR for the FRA & FA would be expected to broadly include:
an explanation of the methodology used to define the safety functions the set of safety functions for the facility an explanation of the methodology used to allocate functions and the final set of allocations the technical basis for modifying high-level functions of predecessor plants in the new design.
a complete set of functional requirements necessary to satisfy the plant goals identification of how personnel and automatic systems perform the functions the technical basis for all function allocations NUREG-0711, Chapter 4, Section 4.4, provides the individual review criteria that are used to guide the staff review of both IPs and RSRs for FRAs and FAs. As the Hl-2210328 document is presented as an RSR, staff observations and feedback are given from a perspective of a completed RSR being submitted following an IP. It should be noted that discussion presented here does not represent a regulatory review nor a finding on the adequacy of the FRA & FA RSR provided in Hl-2210328. Additionally, although the specific request was for feedback on Hl-2210328 (an RSR), since HPP-160-1014, SMR-160 Human Factors Engineering Program Management Plan, (an IP) was also available, it too was taken into consideration to supplement certain Hl-2210328 observations.
In light of the above points, the following observations and feedback consider the contents of the Hl-2210328 document against the relevant criteria of Section 4.4 (it should be noted that some criteria below are summarized at a high-level for the sake of brevity):
4.4(1) - The applicant should use a structured, documented methodology reflecting HFE principles to perform FRA and FA.
o Staff observations and feedback: The Hl-2210328 white paper provides examples of a structured methodology being applied to identify the high-level functions needed to meet plant safety goals and then to decompose them down to the level of the discrete systems and processes that are required. Decisions regarding allocations to automated, shared, or manual approaches to fulfilling those functions then appear to be made using a structured approach as well. It was also noted that one of the referenced documents, HPP-160-1014, provides a generic overview of the process used in the example, with a standardized approach being implemented via Section B.3.0. This overall approach appears to be an appropriate method for meeting this acceptance criterion.
4.4(2) - The applicants FRA and FA should be performed iteratively to keep it current.
o Staff observations and feedback: Section 1.2 of Hl-2210328 implies that the plant function identification report will be revised as needed during the HFE design process and that a tracking system will be used to capture any changes in functions associated with subsequent revisions. The additional white paper HPP-160-1014 was referenced for comparison and Section B.2.2.2, Function Allocation Methodology, was noted to state that the FA will be an iterative process. This overall approach appears to be an appropriate method for meeting this acceptance criterion and reasonable given the information described in the white paper. The review of this approach will be conducted during the review of the submitted operating license application in the future.
4.4(3) - The applicant should describe the plants functional hierarchy, including, as appropriate goals, functions, processes, and systems.
o Staff observations and feedback: NUREG-0711 breaks this criterion down into several attributes; observations of each are included below:
Comparing goals, functions, processes, and systems with the predecessor or reference plants and systems, i.e., the previous ones on which the new plant is based. Identifying the differences between the proposed and reference plants and systems. Documenting the technical basis for modifications to high-level functions in the new design (compared to the predecessor design).
This is mentioned in Section B.2.1.1 of HPP-160-1014 as being part of the FRA methodology. It is not clear where and how the results of this comparison will be presented though as the CVCS FRA/FA example provided in Hl-2210328 do not appear to address it.
Justifying a new/unique design that is not an iteration of any previous existing designs from other vendors is an option.
Defining, for each safety function and other plant function (e.g., electrical power generation), the set of system configurations or success paths that are responsible for, or able to carry out the function.
The CVCS FRA/FA example provided in Hl-2210328 appears to show the application of an appropriate method for meeting this acceptance criterion and the review of this approach will be conducted during the review of the submitted operating license application in the future.
Decomposing the functions, starting at high-level functions and continuing to lower levels, until a specific critical end-item requirement emerges. The functional decomposition should address the following levels: high-level functions, processes, specific plant systems and components, and human actions.
The CVCS FRA/FA example provided in Hl-2210328 appears to show the application of an appropriate method for meeting this acceptance criterion and the review of this approach will be conducted during the review of the submitted operating license application in the future.
4.4(4) - For each high-level function, the applicant should identify requirements related to purpose, as well as relevant conditions and parameters.
o Staff observations and feedback: The CVCS FRA/FA example provided in Hl-2210328 appears to show the application of an appropriate method for meeting this acceptance criterion and the review of this approach will be conducted during the review of the submitted operating license application in the future.
4.4(5) - Applicants should allocate functions to a level of automation and identify the technical bases for the allocations.
o Staff observations and feedback: The CVCS FRA/FA example provided in Hl-2210328 appears to show the application of an appropriate method for meeting this acceptance criterion and the review of this approach will be conducted during the review of the submitted operating license application in the future.
4.4(6) - The applicants FA should consider not only the primary allocations to personnel, but also their responsibilities to monitor automatic functions and assume manual control when necessary.
o Staff observations and feedback: The CVCS FRA/FA example provided in Hl-2210328 appears to show the application of an appropriate method for meeting this acceptance criterion and the review of this approach will be conducted during the review of the submitted operating license application in the future.
4.4(7) - The applicant should describe the overall role of personnel by considering all functions allocated to them.
o Staff observations and feedback: The CVCS FRA/FA example provided in Hl-2210328 shows allocations being made to operators. Since this is one of several FRAs & FAs that will need to be done to cover the various plant systems, it appears that the overall process will be consistent with the finalized RSR for FRA/FA being able to aggregate this information into a compete characterization of the operator role in the fulfillment of the plant safety goal. Section B.1.2 of HPP-160-1014 does discuss that the FA should provide a framework for understanding the role of personnel and Section B.2.2.3 appears to indicate that function identification reports will capture the human actions to be evaluated in the task analysis. However, beyond this, its not clear whether the intent is to aggregate and summarize the results of the various reports as part of the FRA/FA RSR or whether that would appear subsequently with the task analysis RSR.
4.4(8) - The applicant should verify that the FRA and FA accomplish the necessary identification of functions and that allocations are appropriate.
o Staff observations and feedback: Section B.1.2 of HPP-160-1014 indicates that the HFE team will adjust the allocation of functions in an iterative manner as necessary, including in response to insights from workload analysis. Hl-2210328 Section 2.3 appears to provide an example of the type of HFE open items tracking where the need for such changes would be tracked. From the structure of HPP-160-1014, it appears that subsequent HFE elements (e.g., Verification and Validation) should provide a means to verify the adequacy of the FRA & FA.
However, further clarification of the approach in this regard would be helpful.
NOTE: As mentioned earlier, HPP-160-1014 was noted to be available in ADAMS and was used to supplement providing feedback on Hl-2210328. However, HPP-160-1014 was not the focus of the observations provided here. If specific feedback is also wanted on HPP-160-1014, SMR (Holtec) a distinct white paper feedback project for that document can be requested.
REFERENCES
- 1. Human Factors Engineering Presentation Slides ML23165A082-Proprietary
- 2. Human Factors Engineering Presentation Slides ML23165A083-Public
- 3. SMR-160 Human Factors Engineering Program Management Plan HPP-160-1014, ML23165A085-Proprietary
- 4. SMR, LLC HI-2210328, Functional Requirements Analysis and Function Allocation for Chemical and Volume Control System - ML23165A086-Proprietary
ML23165A081 Principal Contributor(s): Jessie Seymour, Division of Reactor Oversight, Operator Licensing and Human Factors Branch, NRR/DRO/IOLB