Features
· Makes it possible to check the monitor calibration by positioning an ionization chamber into the acrylic block, capable to measure in any gantry angles
· Slides into the accessory tray of the LINAC
The test object is an acrylic device to check the constancy of the dose monitor calibration of linear accelerators easily, which is the most important parameter for correct patient treatment. The basic component is an acrylic block with a hole to insert Farmer type ionization chamber. Adapters for other chamber types are available upon request. The chamber is connected to a dosemeter. The measuring depth of the chamber is 16 mm or 33 mm depending on the orientation of the acrylic block. The block is mounted to two appropriate plates, which is inserted into the accelerators accessory holder. The type of the accelerator has to be specified, since the mechanical design of the accessory holder geometry differs with the type of linear accelerator. For constancy tests, the measuring results are compared with previous measurements under identical irradiation conditions.