Development of an extrapolation chamber for the calibration of beta-ray applicators

An extrapolation chamber was designed and constructed, and its performance was studied in beta radiation fields. The characteristics of this chamber and the measurement procedures used for the calibration of beta-ray applicators are discussed in this work. The surface dose rate of a planar /sup 90/Sr+/sup 90/Y applicator was also obtained using the extrapolation chamber, and the results were compared with the Amersham calibration certificate. An agreement within 2.7% was verified.