Constancy checks of well-type ionization chambers with external-beam radiation units.

ABSTRACT: Constancy checks of a well-type ionization chamber should be performed regularly as part of a quality assurance regime. The goal of this work was to test the feasibility of using a linear accelerator and an orthovoltage unit to check the constancy of a well-type chamber's response to an external radiation source. The reproducibility, linearity with dose, variation with dose-rate, and variation between energy-matched units of the well-type chamber response when exposed to 6 MV beams was examined. The robustness to errors in establishing the measurement conditions, including setting the source-to-surface distance and gantry angle, rotation of the chamber around the central axis of the beam, and the effect of changing the length of the chamber cable exposed to the field, were tested. The repr

SUBMITTER: Hackett SL 

PROVIDER: S-EPMC5691027 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature