Participates in the clinical practice of radiation oncology external beam physics through the calibration of radiation beams from treatment units, the definition of the operational characteristics of the treatment units obtained by measurement on those units, the establishment of a dosimetric system based upon the calibration and operational characteristics which enables the accurate delivery of the prescribed dose, the modeling of radiation beams for the purposes of treatment planning and documentation, and the review of the technical aspects of the treatment delivery system to ensure that the treatment prescription is being delivered in a safe and accurate manner.  The clinical privileges of the qualified medical physicist should be delineated to the appropriate category of medical st