2018 | AFC ACCOMPLISHMENTS 103 Figure 2. Fission gas puncture unit shown during testing (top left and right) and puncture tool shown after successful puncture with minimal dulling of tip (bottom). tests on novel fuel concepts, which could highlight irregular irradiation behavior much earlier than the traditional approach of using full-scale irradiation campaigns. In addition, the sub-capsule design and small specimen size allow for separate effects testing of various irradiation parameters that are otherwise difficult to obtain using full-size designs. For example, the small specimen size removes temperature gradients that are present in larger fuel specimens during irradiation. Separate effects data on currently existing fuels retrieved as part of the MiniFuel project is expected to contribute as input data to fuel performance codes. While the small specimen size has advantages in regard to separate effects testing, it also creates challenges for post-irradiation disassembly and examination. Significant development and adaptation of previously established methods was necessary to ensure the successful retrieval of fuel specimens and the collection of meaningful data.The first set of MiniFuel irradiations, which included 0.8mm uranium nitride microspheres and 1mm tri-structural isotropic (TRISO) particles, were loaded into