Dose evaluation to patients irradiated by 60Co beams, by means of direct measurement on the incident and on the exit surfaces.

A method for direct dose measurements on a patient treated with 60Co beams, is described. A home-made multi-probe dosimeter with silicon diodes as detectors is described. Measurements were performed on the entrance as well as on the exit fields, and a correlation was established with the mid-line dose. The influence of field size, SSD, patient thickness, and inhomogeneities was investigated.