Assurance of the traceability chain for 131I measurement

The paper presents some recent results of the Radionuclide Metrology Laboratory (RML) from IFIN-HH, concerning the assurance of the international traceability for the measurement of 131I solution aimed to continue the national chain for nuclear medicine applications in Romania. The following sequences of the traceability are presented: the absolute standardization of solution by the 4πβ-γ coincidence, efficiency extrapolation method and participation in the BIPM.RI(II)-K1.I-131 key comparison; and recalibration of the CENTRONIC IG12/20A ionization chamber secondary standard. The participation in the IAEA/SSDL (SSRL) 131I comparison is also presented.