Per Øivind Braarud

Capturing control room simulator data with the HERA System

The Human Event Repository and Analysis (HERA) system has been developed as a tool for classifying and recording human performance data extracted from primary data sources. This paper reviews the process of extracting data from simulator studies for use in HERA. Simulator studies pose unique data collection challenges, both in types and quality of data measures, but such studies are ideally suited to gather operator performance data, including the full spectrum of performance shaping factors used in a HERA analysis. This paper provides suggestions for obtaining relevant human performance data for a HERA analysis from a control room simulator study and for inputting those data in a format suitable for HERA.

An empirical study of HRA methods - overall design and issues

A diversity of Human Reliability Analysis (HRA) methods are currently available to treat human performance in Probabilistic Risk Assessments (PRAs). This range of methods reflects traditional concerns with human-machine interfaces and with the basic feasibility of actions in PRA scenarios as well as the more recent attention paid to Errors of Commission and decision- making performance. Given the differences in the scope of the methods and their underlying models, there is a substantial interest in assessing HRA methods and ultimately in validating the approaches and models underlying these methods. A significant step in this direction is an international evaluation study of HRA methods, based on comparing the observed performance in simulator experiments with the outcomes predicted in HRA analyses. Its aim is to develop an empirically- based understanding of the performance, strengths, and weaknesses of the methods. This paper presents the overall methodology for this initial assessment study.

International HRA Empirical Study, Overall Methodology and HAMMLAB Results

The International HRA Empirical Study addresses the need for assessing HRA (Human Reliability Analysis) methods in light of human performance data. The study is based on a comparison of observed performance in HAMMLAB simulator trials with the outcomes predicted in HRA analyses. The project goal is to develop an empirically-based understanding of the performance, strengths, and weaknesses of a number of different HRA methods. This chapter presents the overall methodology for the initial assessment study (the pilot study), provides an overview of the HAMMLAB results and presents insights from the initial assessment.

A Simulator Experiment Investigating the Effects of Masked Indicators in a NPP Emergency Control Task: Scenario and Design:

This paper describes the scenario and participants of a simulator experiment investigating the performance of nuclear power plant (NPP) control room crews in a realistic accident scenario where multiple failures lead to masking of relevant diagnostic information. These conditions challenge emergency operating procedures and require crews to engage in knowledge-based problem solving. The study placed particular emphasis on generating rich operational descriptions of crew behavior and performance-shaping factors.

Task Complexity as a Factor for Human Reliability Assessment

Context or Performance Shaping Factors are important elements of Human Reliability Assessment methods. This paper describes an approach to task complexity for process control, describes the concept as a context factor for human reliability, and report example of results on task complexity from a simulator experiment on human performance in accident operation.

Studies for the Future

Over the coming years, new generations of reactors are going to be introduced with new reactor designs and new control room technologies. Also, extensive upgrades and modernisations of the current fleet of reactors will take place, introducing new control room technologies. In light of that, this chapter discusses what kind of HAMMLAB research is needed in the future. A set of relevant research topics are suggested, future research methods are discussed, and technical requirements for future studies in HAMMLAB are considered.

Improving the Empirical Basis for Human Reliability Assessment by Simulator Experiments

The OECD Halden Reactor Project has incorporated Human Reliability Assessment (HRA) as a central point in its research program for 2003–2005. As part of this, several activities are undergoing in co-operation with Idaho National Engineering and Environmental Laboratory and the U.S. Nuclear Regulatory Commission to support the need for more empirical data for HRA. This paper describes how empirical data from simulator studies in HAMMLAB (HAlden huMan-Machine LABoratory) may support improvements to HRA methods.