About the project
The project is implemented within the framework of the International Atomic Energy Agency Coordinated Research Project in Radiation Metrology E24026 (2025–2028). This program is directed towards strengthening academic capacity in low- and middle-income countries through doctoral research focused on advanced dosimetric methodologies.
A central objective is the preparation of highly qualified specialists capable of transferring knowledge to future generations, while fostering sustainable international cooperation.
In the broader context, the initiative contributes to the reliability of radiation measurements and the enhancement of safety and effectiveness in medical applications of ionizing radiation.
Project summary
Accurate dosimetry is essential to ensure patient safety, optimize image quality, and comply with radiation protection principles in diagnostic radiology. Dosimeters with ionization chambers and semiconductor detectors are widely used for measuring standard and special quantities in X-ray diagnostic imaging. To ensure reliable and comparable measurements, these instruments must be calibrated with traceability to international standards. Calibration of diagnostic dosimeters is generally performed using radiation qualities defined in IEC 61267. However, standard does not cover the full range of clinical radiation qualities and the range is continuously evolving. Due to the significant energy dependence of diagnostic dosimeters, differences between laboratory calibration spectra and clinical radiation spectra introduce additional measurement uncertainty. Recent research within the EURAMET project 22NRM01 TraMeXI proposes new radiation qualities to improve the coverage of clinical conditions and extend traceability for special quantities.
In Uzbekistan, a SSDL was established in 2022 under the IAEA project UZB 6015. Although initial radiation qualities and calibration capabilities have been implemented, full national-level traceability covering extended radiation qualities and special quantities has not yet been established. In addition, there is a strong regional demand for calibration services in Central Asia, highlighting the strategic importance of developing harmonized national calibration procedures.
Overall Objective
The overall objective of this research is to establish national-level traceability and develop harmonized calibration and measurement procedures for dosimeters used in X-ray diagnostic imaging.
The specific objectives are to
Characterize radiation qualities (RQR, RQA, and RQT) and X-ray field parameters (field profiles, homogeneity, scattered radiation, and collimator effects);
Establish standard and newly proposed radiation qualities;
Develop calibration procedures and uncertainty budgets for air kerma, HVL and tube voltage;
Investigate differences between calibration and clinical radiation conditions by comparison of XMM response for air kerma, tube voltage and HVL;
Dosimeter testing in new radiation qualities;
Validate the developed procedures through bilateral comparisons with IAEA DOL and supplementary comparisons among COOMET member countries;
Measurements and comparisons of results in clinical and laboratory conditions.
Expected Outcomes
Development of National Calibration Procedures
Creation of standardized calibration methods for diagnostic radiology dosimeters in accordance with recommendations from international initiatives, including the IAEA TRS-457 update project and the EURAMET 22NRM01 TraMeXI project.
Establishment of New Radiation Qualities
Introduction of additional reference radiation qualities in calibration laboratories to more accurately reflect the spectrum of X-ray beams used in clinical practice.
Provision of Traceability for Key Dosimetric Quantities
Ensuring traceability of measurements for air kerma, air kerma length product, air kerma area product, and specific diagnostic parameters (practical peak voltage, total filtration, and half-value layer).
Strengthening of National and Regional Dosimetry Infrastructure
Implementation of a sustainable traceability framework that supports calibration services within Uzbekistan and provides a foundation for extending expertise and services to neighboring Central Asian countries.