The FAX06 and the MAX06 Computational Voxel Phantoms
Matter, after having been exposed to ionizing radiation, cannot express itself in terms of absorbed or equivalent dose. Consequently, the equivalent dose in tissues of the human body cannot be measured directly. Indirect measurements of equivalent dose can be made by radiation detectors, but they are restricted to locations on the surface of the human
body, thereby excluding most of the radiosensitive organs and tissues from this method of equivalent dose assessment.