The CIRS Model 002PRA IMRT phantom is designed to address the complex issues surrounding commissioning and comparison of treatment planning systems and verification of individual patient plans and delivery. The CIRS 002PRA phantom properly represents human pelvic anatomy in shape, proportion and structure as well as density. This enables thorough analysis of both the imaging and dosimetry system. The phantom is constructed of proprietary tissue equivalent epoxy materials. Linear attenuations of the simulated tissues are within 1% of actual attenuation for bone and water from 50 keV to 25 MeV. The phantom is elliptical in shape, approximates the size of an average patient, and has a tissue equivalent, three dimensional skeleton. Tissue equivalent interchangeable rod inserts for ionization chambers allow for point dose measurements in multiple planes in the phantom and film calibration.* The phantom also supports film dosimetry with not only standard radiographic films but also GafChromic? media. Additional inserts are available to support a variety of other detectors including TLD¡¯s, MOSFET, and diodes. The Model 002PRA includes four different Electron Density reference plugs which can be interchanged in five separate locations within the phantom. The surface of the phantom is etched with grooves to ensure proper orientation of the CT slices and accurate film to plan registration. CIRS IMRT phantoms are manufactured from tissue equivalent materials that mimic within 1% from 50 keV to 25 MeV for accurate simulation from CT planning to treatment delivery. The interchangeable rod design allows the phantom to accommodate a multitude of dose measurement devices such as ion chambers, TLD, diodes and MOSFET’s in the same location within the phantom.* Phantom cross sections accommodate GafChromic(r) or standard ready-pack films.