Activity standardization of 131I at CENTIS-DMR and PTB within the scope of a bilateral comparison

The activity of an 131I solution was measured at the Cuban Institute, CENTIS-DMR, as well as at the German National Metrology Institute, PTB, within the scope of a bilateral comparison. In particular, the comparison is aimed at an investigation of the measurement capabilities of CENTIS-DMR which provides activity standards in Cuba and organizes national comparisons, placing a particular emphasis on radionuclides for nuclear medicine, such as 131I. Both institutes applied liquid scintillation counting techniques with efficiency tracing as well as secondary standardization procedures by means of calibrated ionization chambers and gamma-ray spectrometers. The results were checked for consistency and a good agreement was found. Moreover, a virtual link of the Cuban result to the International Reference System (SIR) at the Bureau International des Poids et Mesures (BIPM) is discussed.