To avoid the illicit use of nuclear materials, EURATOM and international safeguards authorities have set up systems to verify the correctness and completeness of States’ declarations about nuclear-related activities. The intrinsic parts of the safeguards and verification systems are reliable quality control tools used for calibration of methods, quality control, and assessment of method performance with isotope mass spectrometry and radiometry techniques.
Two JRC Institutes, the Institute for Reference Materials and Measurements (IRMM) and the Institute for Transuranium Elements (ITU), jointly produced the uranium reference materials, IRMM-1000a and IRMM-1000b. The production was in accordance with ISO Guides 34 and 35. The uranium reference materials were certified for the production date based on the 230Th/234U radio-chronometer, i.e. the date of the last chemical separation of these two radionuclides. Such certified reference materials (CRMs) are not only required for proper validation of measurement procedures in nuclear safeguards, but also in nuclear forensics and security in order to determine the ‘age’ of (seized) uranium samples and to provide traceability of the measurement results.
Read more in:
Z. Varga et al.: “IRMM-1000a and IRMM-1000b uranium reference materials certified for the production date. Part I: methodology, preparation, and target characteristics“, Journal of Radioanalytical and Nuclear Chemistry 307 (2016) 1077-1085, doi:10.1007/s10967-015-4227-x
C. Venchiarutti et al.: “IRMM-1000a and IRMM-1000b: uranium reference materials certified for the production date based on the 230Th/234U radiochronometer. Part II: certification“, Journal of Radioanalytical and Nuclear Chemistry 308 (2016) 105-111, doi:10.1007/s10967-015-4368-y
C. Venchiarutti et al.: “REIMEP-22 inter-laboratory comparison: U Age Dating – determination of the production date of a uranium certified test sample“, Radiochim. Acta 2015; Volume 103, Issue 12, Pages 825–834, doi:10.1515/ract-2015-2437