Determination of the operational characteristics of ionization chambers of dose calibrators

Most of dose calibrators operate with well-type ionization chambers. In this work the operational characteristics of two well-type ionization chambers made at IPEN, were determined. Sealed standard radiation sources and unsealed liquid sources were measured. Two systems were mounted using electrometers, a high-voltage source and digital multi meter. A continuous control was realized by measuring source activities with three calibrator systems. The medium-term stability test using the standard sources and short-term calibrator systems. The medium-term stability test using the standard sources and short-term stability test using other sources showed good performance of all chambers. The two IPEN systems showed good stability, with response variations less than the recommended limit of 10%. (author)