Draft Function Allocation Framework and Preliminary Technical Basis for Advanced SMR Concepts of Operations

Abstract

EXECUTIVE SUMMARYThis report presents preliminary research results from the investigation into the development of new models and guidance for Concepts of Operations in advanced small modular reactor (aSMR) designs. aSMRs are nuclear power plants (NPPs), but unlike conventional large NPPs that are constructed on site, aSMRs systems and components will be fabricated in a factory and then assembled on site. aSMRs will also use advanced digital instrumentation and control systems, and make greater use of automation. Some aSMR designs also propose to be operated in a multi-unit configuration with a single central control room as a way to be more cost-competitive with existing NPPs. These differences from conventional NPPs not only pose technical and operational challenges, but they will undoubtedly also have regulatory compliance implications, especially with respect to staffing requirements and safety standards.For example, the impact of aSMR designs on operational and regulatory considerations, such as workload, situation awareness, human reliability, staffing levels, and the appropriate allocation of functions between the crew and various plant systems that are likely to be highly automated is largely uncertain and will remain uncertain until empirical research data become available to support the development of sound technical bases. Experience with aSMRs outside of the US Navy is limited, existing human factors and systems engineering design standards are not current in terms of human interaction basics for automated systems, and there is a lack of a good functional allocation and staffing model that takes into account static or dynamic allocation.Given these uncertainties and other issues, new Concepts of Operations models must be researched and developed for aSMRs. Concepts of Operations describes the characteristics of a proposed system from the viewpoint of an individual who will use that system. It is used to communicate the quantitative and qualitative system characteristics of the plant to all stakeholders, provides the basis for procedures, and serves as input to Human Factors analyses. New Concepts of Operations models are developed by conducting an in-depth analysis of the characteristics and attributes of the concepts of operations of future aSMR. By doing this, insights into how the role and function of humans in the plant might be affected by advanced aSMR technologies, and, conversely, how the operation of these plants might be influenced by the need to integrate human factors principles in the design are revealed.objective of this research is to establish the technical bases for non-traditional concepts of operations for aSMRs (i.e., Develop new models and guidance for Concepts of Operations), with the goal of addressing specific human factors challenges related to non-traditional concepts of operations, and the associated changes in the allocation of functions to human and system agents. This includes the development of functional allocation principles as one of the primary decision criteria for ...

Development of a Technical Basis and Guidance for Advanced SMR Function Allocation

“…As explained in t he September 2012 and April 2013 milestone report s [22], [23], WDA has never been applied in the development or analysis of concepts of operation in the nuclear industry. T his does not mean that AdvSMR designers should try to innovate just for the sake of innovation; rather it means that we should recognize that new technology often requires not just new design techniques, but also new mental models.…”

“…As explained in previous reports (cf. [23]), the Function Allocation process forms one of the elements conducted by NPP designers as part of the Human Factors Engineering Program in conformance with the requirements of NUREG-0711 (Human Factors Engineering Program Review Model). It should be emphasized that FA is not a stand-alone process and would always be performed in association with either a power plant upgrade effort (for example control room upgrade) or as part of systems engineering for a new plant.…”

“…T he April 2013 milestone report [23] described how the innovative design concepts expected for Adv SM R plants will require new approaches to the analysis and definition of human factors requirements. Of particular importance is the need to achieve more efficient and cost-effective operations, not only in the control room, but also for the plant as a whole.…”

“…T he April 2013 milestone report of this project [23] documented a review of existing FA methods and models, and demonstrated that they still have some technical gaps. T herefore, some additional FA research has been performed in order to develop this FA framework properly.…”

“…An extensive review of FA methods and models, and a description of their applicability to the Concepts of Operations project can be found in the previous milestone report for this project [23]. However, for this report the research team included a few additional sources on FA.…”