The decision of 21/11/2016 establishing the quality control procedures for radiodiagnostic installations used in image-guided interventional procedures states in section 4.2 "Equipment required for quality control" the need for a patient-equivalent phantom with a cross-section of at least 20 cm x 20 cm and a thickness of 20 cm ± 0.5 cm in polymethyl methacrylate (PMMA). This thickness must be adjustable as needed by increments of ± 3 cm using 1 cm layers.
However, due to the weight of such a phantom, commercial models are generally composed of a set of plates of different thicknesses (for example 5 mm, 10 mm, and 20 mm). Nothing in the above-mentioned decision prohibits this type of solution, as long as the supplied plates allow total thicknesses of 17, 18, 19, 20, 21, 22, and 23 centimeters with an associated uncertainty of ± 0.5 cm.
