The absolute standardization methods of ³²p for calibrate nuclear medicine instruments in Indonesia

The absolute standardization of ³²P radioactive sources employed to calibrate nuclear medicine instruments has been conducted at PTKMR-BATAN. We deemed this activity to be necessary since ³²P used in the nuclear medicine fields has a short half-life, and in order to obtain a result of quality measurement, it requires a special treatment. Moreover, in Indonesia, the use of nuclear medicine techniques has developed rapidly. We prepared all the radioactive sources with a gravimetric method by using a KERN ABT 220-5DM semi-micro type scale, traceable to the International Unit System. We conducted the ³²P standardization by employing a4πβ(PS)-γ coincidence method with ⁶⁰Co as a tracer; meanwhile, we conducted the impurity measurement by employing a beta spectrometer system. The result of ³²P absolute measurement was 380.05 Bq/mg with a 0.68-percent range uncertainty, with a k=2 coverage factor. This value was used to calibrate a ''Capintec CRC-7BT'' dose calibrator that was a secondary standard instrument in PTKMR-BATAN. The results showed us that the calibration factor of the ''Capintec CRC-7BT'' dose calibrator was 1.12 with a 4.7-percent uncertainty. (author)