Calibration of semiconductor detectors for dose assessment in total body irradiation

The aim of this paper is to discuss the measurements carried out to implement 'in vivo dosimetry' with EDP-30 diodes in total body irradiation (TBI) techniques. Exit calibrations and calibrations behind cerrobend protection blocks showed the importance of calibrating diodes in all relevant clinical conditions. Special attention was given to calibration of diodes behind cerrobend blocks. Dependence of the calibration factors on the thickness of the shielding blocks was, therefore, studied. This dependence was again studied after adding a wax cap to the diode and when the ionisation chamber was placed at the same depth as the measuring point of the diode. Temperature dependence in diode sensitivity and dependence on accumulated dose for diodes response and for temperature correction factors were also examined.