Work

On measurement standards and techniques in performance evaluation of a modern X-ray generator

Year: 2025

Type: article

Abstract: X-ray generators play a crucial role in diagnostic imaging and radiation protection, with standards IEC 61267 and ISO 4037-1 governing the beam commissioning process. However, insufficient detail in measurement techniques and omissions in these standards may introduce errors that affect performance evaluation. This study assesses the performance of a modern X-ray generator during beam commissioning, focusing on voltage accuracy, ripple voltage, and measurement techniques in relation to compliance with these standards. A metrological X-ray system was evaluated using a combination of invasive and non-invasive measurements, employing instruments such as a high-voltage divider, oscilloscope, multimeters, X-ray multimeter, and radiation detectors. Voltage deviation, ripple voltage analysis, and real-time spectrum evaluation were conducted under various conditions. The generator met most of the standard requirements, with voltage deviations consistently below 0.5% across different instruments. The comparison between practical peak voltage and average voltage showed minimal differences, suggesting that average voltage measurements could be broadly applicable. Ripple voltage analysis revealed drawbacks in peak-to-peak versus root-mean-square measurements, emphasizing the importance of measurement bandwidth and the calibration challenges associated with invasive methods. Furthermore, ripple limits based on DC offset assumptions do not adequately reflect the actual impact of ripple on dosimetric quantities. Our results indicate that ripple-averaging effects mitigate these deviations, highlighting the need for further research. These findings suggest potential refinements in ISO 4037 and IEC 61267 regarding measurement techniques, ripple characterization, and uncertainty specifications. While the modern X-ray generator demonstrates solid compliance with current standards, clearer guidelines on voltage accuracy and ripple measurement are necessary. Standard revisions should address measurement bandwidth, discrepancies in ripple measurements, and practical instrument limitations to improve accuracy and ensure reliable X-ray system assessments in clinical and research applications.

Source: Radiation Physics and Chemistry

DOI: 10.1016/j.radphyschem.2025.113510