The radiations considered in the Report are x rays with peak energies in the range from 10 keV to 50 MeV and gamma-rays from radionuclide therapy units. The Report describes and discusses the many recommended procedural details for the continuing proper delivery of absorbed dose by radiation therapy machines. The Report also considers the salient features of exposure and absorbed dose measurement that relate them to the national radiation standards, and includes a discussion of the uncertainty in the delivery of the absorbed dose. This Report addresses the rationale, the care and use of instruments, and the measurements required for radiation therapy machines.
Discussion is limited to a single treatment field and a water or tissue phantom.
Major sections of the Report cover basic parameters of photon beams and principles of dosimetry, national radiation standards, secondary standards, field instruments, commission, calibration and other measurements on radiation therapy machines, and uncertainty in delivery of absorbed dose. The Report also includes an appendix setting out definitions of terms relevant to dosimetry for radiation therapy.