Abstract This paper presents the outcomes of the research project TACR TK04010018, which aimed to develop a methodological framework for the application of uncertainties in ultrasonic testing (UT) results, particularly for applications in the nuclear energy sector. The project, conducted by CVŘ and ÚJV between 2022 and 2025, focused on developing a methodology for determining and expressing the uncertainty of ultrasonic testing results. The evaluation concentrated on the accuracy of defect sizing using pulse-echo and phased array techniques. A comprehensive experimental program generated tens of thousands of values, which were statistically analyzed to determine Type A uncertainties based on testing parameters. The findings revealed that UT result accuracy is significantly influenced by measurement conditions, human factors, and evaluation methodology. Uncertainty can be meaningfully quantified only for specific defects with defined parameters. The project introduced a tiered approach to uncertainty determination, enabling practical application depending on the required level of result accuracy. These outcomes enhance the reliability of UT results and provide a foundation for further research, particularly in the area of system-related Type B uncertainties.
Mareš et al. (Sat,) studied this question.