Advanced nuclear reactor designs and advanced fuel types offer safety features that may reduce environmental consequences in an accident scenario when compared to conventional reactors and fuels. One advanced reactor fuel is tri-structural isotropic (TRISO) fuel particles which are approximately 0.9 mm in diameter. TRISO particle mobility, assuming the particle is unruptured and the encapsulated radionuclides are contained, was explored by a theoretical examination of transport through atmosphere, soil and groundwater, surface water, and non-human biota pathways. TRISO particles are too large and dense to travel in the atmosphere except under extreme conditions. TRISO particles are also too large to penetrate most soil profiles and so cannot be transported to or by groundwater. TRISO particles will settle out of the water column in surface waters and thus the transport will depend on the energy of the water body (e.g., waves or floods). TRISO particles could be transported by non-human biota. The size of TRISO particles could allow them to be intentionally ingested by non-human biota as a gastrolith or mimic something typical in an organism's diet. Generally, TRISO particles will have reduced environmental mobility compared to releases of radionuclides in the event of a conventional nuclear reactor accident. The extent of transport has implications in emergency planning zone designations and other considerations for licensing and deploying TRISO-fueled reactors. Further research and experimental work exploring TRISO particle mobility is required to understand the full environmental mobility of TRISO particles in the environment.

与常规反应堆和燃料相比，先进的核反应堆设计和先进的燃料类型提供的安全功能可以在事故场景中减少环境后果。一种先进的反应堆燃料是直径约为0.9毫米的三结构各向同性（TRISO）燃料颗粒。通过对通过大气，土壤和地下水，地表水和非人类生物区系通道的迁移进行理论研究，探索了TRISO粒子的迁移性（假设粒子未破裂且包含封装的放射性核素）。除极端条件外，TRISO颗粒太大且致密，无法在大气中传播。TRISO颗粒太大，无法穿透大多数土壤剖面，因此无法运输到地下水或被地下水运输。TRISO颗粒将从地表水中的水柱中沉降出来，因此其传输将取决于水体的能量（例如，波浪或洪水）。TRISO颗粒可以通过非人类生物区系运输。TRISO颗粒的大小可以使它们被胃口石或类似有机物饮食中的典型食物的非人类生物有意摄入。通常，与常规核反应堆事故中的放射性核素释放相比，TRIOS颗粒的环境迁移率将降低。运输的范围对紧急计划区的指定以及许可和部署由TRISO燃料的反应堆的其他考虑事项都有影响。