Zinc dust has distinct physical properties and hazard characteristics — it is pyrophoric at fine particle sizes — that place it in a separate SITC category from bulk zinc scrap. Importers handling fine zinc residues or powders should verify the correct classification with a licensed customs broker, as misclassification between dust and scrap can affect both duty treatment and safety/regulatory compliance at entry.

Smelters generally require a material specification sheet confirming zinc content, alloying elements (particularly aluminum and copper), and absence of prohibited contaminants such as cadmium above threshold levels. Basel Convention movement documents may also be required depending on the country of origin, and some ports require a pre-shipment inspection certificate to confirm the material is non-hazardous recyclable waste rather than a prohibited export.