Determination of ¹⁵³Sm Radioactivity for Comparative Studies Among Laboratories

In order to obtain valid and accurate measurement results, the testing laboratory should pay attention to the quality assurance program. Participation in interlaboratory comparison program is one tool to evaluate and gain confidence that the measurement results issued by a laboratory is valid. The Neutron Activation Analysis Laboratory (NAA), Center for Science and Technology of Advanced Materials, has participated in interlaboratory radioactivities measurement program for laboratory has gamma spectrometry equipment at BATAN. In this program each laboratory received two ¹⁵³Sm radionuclides - one was used as a sample while the other one was employed as a benchmark standard. Determination of ¹⁵³Sm radionuclide activity was performed by a comparative method, using PSTMB-3 and PSTBM-4 gamma spectrometers, In order to ensure that the counted area of the peak of interest could be properly counted, the Quantification Limit (LC) and Detection Limit (LD) with 95 % confidence level were determined using the Currie method. The activity measurement with PSTBM-3 detector on August 12, 2016 at 14:59:05 WIB resulted in the activity of 158347.48 ± 9627.52 Bq while using PSTBM-4 detector on August 12, 2016 at 14:59:05 WIB the activity recorded was 162258.12 ± 7594.68 Bq. This values were then compared with the measurement by the Organizer Laboratory, and it was found that the measured activity difference was below 10 %; thus the result of the measurement was valid. (author)