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7 Hot Fuel Examination Facility Neutron Radiography The HFEF TRIGA reactor known as NRAD enables neu- tron-radiography irradiations to verify materials behaviors such as Fuel pellet separations Fuel central-void formation Pellet cracking Evidence of fuel melting Material integrity under normal and extreme condi- tions The NRAD beam tubes were designed for examination of fuel elements to identify areas of interest such as location of fuel for disassembly identification of cracking density varia- tions and hydrides in cladding. NRAD is equipped with two beam tubes and two separate radiography stations. Neutron radiography of elements capsules and loops is performed in the main cell at workstation 4M. Specimens are placed into a radiograph holder that is lowered into the NRAD neutron beam located below the floor. The holders optimally posi- tion the specimen for radiography without excessive neutron scattering. Both dysporosium and cadmium-covered indium foils are used as neutron detector foils these are irradiated in the neu- tron beam then transferred to a film cassette and allowed to decay for three to four half-lives against ordinary X-ray film to form the image. The dysprosium foils used for thermal neutron radiographs of low-enriched fuels and thin structur- al materials produce excellent detail but specimen thickness and fuel enrichment is limited. The indium foils are used for A neutron radiograph of irradiated FFTF fuel.