2844.50.00.00 - Spent (irradiated) fuel elements (cartridges) of nuclear reactors

This HTS category, 2844.50.00.00, specifically encompasses spent (irradiated) fuel elements, also referred to as cartridges, that have been utilized within nuclear reactors. These are materials that have undergone nuclear fission and are no longer suitable for sustaining a nuclear chain reaction but still retain significant radioactivity and valuable isotopes. The primary characteristic is their irradiated state, meaning they have been exposed to neutron flux in a reactor core.

This classification is distinct from its sibling categories, which deal with various forms of uranium (natural, enriched, and depleted), plutonium, and thorium, along with their respective compounds and mixtures. While siblings might cover new or processed nuclear materials, 2844.50.00.00 is exclusively for fuel elements *after* they have been used and removed from the reactor. The "spent" nature is the key differentiating factor, implying prior irradiation and subsequent removal from service.

As this is a leaf node, there are no further subcategories. Therefore, the classification is precise to spent fuel elements themselves. For classification purposes, the defining characteristic remains their designation as spent fuel elements from a nuclear reactor. The physical form (e.g., rods, assemblies) and the specific isotopes present, while contributing to their hazardous nature and handling requirements, do not typically lead to further subdivision within this specific HTS code.