FGMS-poster

Shaffer, Rachel M [Idaho National Laboratory] (ORCID:0000000201045732); Fronk, Ryan G [Idaho National Laboratory] (ORCID:0000000308657464); Fox, Jordan K [Idaho National Laboratory]

DOE OSTI · 3377217

FGMS-poster

Shaffer, Rachel M [Idaho National Laboratory] (ORCID:0000000201045732)·Fronk, Ryan G [Idaho National Laboratory] (ORCID:0000000308657464)·Fox, Jordan K [Idaho National Laboratory]

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Abstract

Idaho National Laboratory (INL) performs post irradiation examination (PIE) of tri-structural isotropic (TRISO)-coated particle fuel to help qualify it for high temperature gas cooled reactors. TRISO fuel compacts are re-irradiated in the Neutron Radiography Reactor (NRAD) to generate the short lived fission products needed for fission product release testing. The Fuel Accident Condition Simulator (FACS) furnace and newly added Screen Neutron Irradiated Fuel for Failure (SNIFF) furnace heat the compacts in helium to temperatures of up to 2,000°C, prompting fission product release—predominantly gaseous xenon and krypton isotopes and condensable products such as cesium—from failed particles. These released isotopes are transported to a fission gas monitoring system (FGMS 1 or FGMS 3), where they accumulate in cryogenic cold traps and are quantified using high-purity germanium (HPGe) detectors. The addition of SNIFF and FGMS 3 increases throughput by enabling simultaneous testing of multiple compacts. Furthermore, automated INL developed software provides continuous, near-real time monitoring of fission product inventories and manages the liquid nitrogen cooling of the traps. These system enhancements improve the efficiency, data quality, and testing capacity of TRISO fuel performance evaluations.

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07 - ISOTOPES AND RADIATION SOURCES 46 - INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY Fission Gas Monitoring System Fission Products Fuel Accident Condition Simulator NRAD Screen Neutron Irradiated Fuel for Failure TRISO fuel

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Shaffer, Rachel M [Idaho National Laboratory] (ORCID:0000000201045732), Fronk, Ryan G [Idaho National Laboratory] (ORCID:0000000308657464), Fox, Jordan K [Idaho National Laboratory]. 2026-06-15. FGMS-poster. https://www.osti.gov/biblio/3377217

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