Full-scale demonstration of human reliability analysis framework for TRIGA research reactor

The Thailand Institute of Nuclear Technology (TINT) and the Korea Atomic Energy Research Institute (KAERI) together developed the human reliability analysis (HRA) framework for the TRIGA research reactor based on the EMpirical data-Based crew Reliability Assessment and Cognitive Error analysis (EMBRACE) and TAsk COMplexity (TACOM) methods with the Human Reliability data EXtraction (HuREX) database for extracting human errors and estimating the human error probabilities (HEPs) of actions during the implementation of emergency operating procedures (EOPs). This study provides a full-scale demonstration of how to use the HRA framework through the Thai Research Reactor-1/Modification 1 (TRR-1/M1) case study to extract human errors of actions and estimate the overall HEPs of the steps and tasks in EOPs. Human error of Type C was mainly gathered as the data source from observations of TRR-1/M1's emergency training. Application of the TACOM method systematically and consistently improved the EOPs by providing how to identify the primitive tasks of human errors using the double-column procedure, the same standard as in nuclear power plants. The HRA event tree from the Technique for Human Error Rate Prediction (THERP) was used to consider human errors without machine or system failures to represent realistic human errors in the estimation of nominal human error probabilities (NHEPs). The highest NHEP task was found to be Task 8 of the loss of coolant accident (LOCA) EOP in error of omission (EOO) mode at 6.929E-01 due to multiple manual operations of valves. Additionally, consideration of performance shaping factors (PSF) significantly increased the HEPs when compared to their NHEPs due to the effects of the complexity of the required task and subjective stress. • TRIGA's HRA framework is combined with EMBRACE, TACOM and THERP methods and the HuREX database. • TRR-1/M1's EOPs are standardized to support primitive task identification and NHEPs' estimation. • The THERP event tree and flowchart of steps provide NHEP estimates from human error without machine failure. • Highest HEP task for TRR-1/M1 is LOCA Task 8 in EOO mode without external effect from PSFs.