A growing number of states and cities prohibit the sale or distribution of polystyrene foam foodservice containers, which means importers must map their distribution geography carefully. Products that are admissible at the federal level may still be unsaleable in key markets, making state-level regulatory tracking an essential part of procurement planning.

Expanded polystyrene (EPS) is produced by steam-expanding polystyrene beads and is widely used for protective packaging and insulation. Extruded polystyrene (XPS) is produced through a continuous extrusion process, yielding a closed-cell structure with higher compressive strength and moisture resistance, making it preferred for below-grade building insulation. The two forms may classify under different HTS subheadings and serve distinct end markets.