Comparative measurements on a series of accelerators by the same vendor.

A series of comparative measurements were conducted during a 12-month period on a series of linear accelerators made by the same vendor. These measurements were conducted during acceptance and commissioning of six Varian model 2100C linear accelerators which had identical beam energies and beam modifiers. Nominal accelerating potentials, scatter measurements, depth doses, beam profiles, wedge and electron beam descriptors are presented. The results show highly similar beam parameters with observed variations being approximately equivalent to the precision of measurement. This similarity implies that a standard data set can be used to validate new commissioning data.