Human Reliability Analysis

Purpose

Human Reliability Analysis aims to identify all ways in which plant operators can intervene in the success or failure of the plant given the procedures for the specific plant. As it relates to AR's, HRA will be a crucial element not only once a plant is operational, but also in the design and licensing phase.

Scope

Human Reliability Analysis for advanced reactors will cover operator actions that result in plant success as well as plant failures related to human error. Since procedures for advanced reactors can be much different between different designs and vastly different compared to LWR procedures, the associated operator actions will likely have high variability which will need to be accounted for.

HRA

Human Reliability Assessment (HRA) is required as part of the final safety analysis report (FSAR) for any licensing application using any of the potential licensing pathways. Hamza and Diaconeasa introduced a framework for incorporating HRA in the early stages of design either at the pre-conceptual or conceptual design phase to develop significant operator actions early, thereby meeting the needs for ARs in their current stage. The PRA Standard for Advanced Non-LWR Nuclear Power Plants [6] specifies technical requirements for the 18 elements needed to create a full-scope PRA, with two PRA Capability Categories, CC-I and CC-II, based on plant, site, or design-specific models. Human actions are incorporated into all 18 PRA elements, with one specific element responsible for HRA, which should be included in both capability categories to ensure the identification of risk significant events. In stakeholder interviews it was determined that a there was particular concern for the development of operator actions in response to multi-day issues and for errors of commission in relation to HRA as these may not be the dominant sources of human error for current LWRs, but could become dominant for ARs. Roadmap actions supported emphasizing the importance of EoCs as a source of human error for ARs:

• Develop Enhancements to Licensing Process
• Develop Industry Recommendations for Regulatory (NRC / CNSC) Guidance on Operator Staffing

A higher level of detail for these actions can be found in the roadmap along with Table 3-2 which summarizes the methods to assess HRA’s impact on AR safety.