Flame-Retardant PS Foam Sheets
Cellular polystyrene sheets with chemical modification for fire resistance in building/construction. Still 3921.11.00.00 as base styrene polymer per subheading note (c). Self-extinguishing.
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Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If chemically modified beyond styrene recognition
Modified polymers not specifically covered go to 'Other cellular' 3921.19 per notes.
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Import Tips & Compliance
• Document flame retardant as modification not changing base polymer
• UL certifications speed clearance
• Avoid 'Other' subheading confusion
Related Products under HTS 3921.11.00.00
Styrene Expanded Polystyrene Foam Sheets
Rigid foam sheets made from expanded polystyrene (EPS), a cellular polymer of styrene, used for insulation and packaging. Classified under HTS 3921.11.00.00 as cellular plates and sheets of styrene polymers per chapter notes on polymer classification. The cellular structure provides buoyancy and thermal insulation properties.
Polystyrene Foam Insulation Panels
Extruded polystyrene (XPS) foam panels designed for building wall and roof insulation. Falls under 3921.11.00.00 as cellular sheets of styrene polymers, confirmed by predominant styrene content. Provides high R-value thermal resistance.
EPS Foam Packaging Sheets
Beadboard expanded polystyrene sheets cut to size for protective packaging of electronics and appliances. Classified in 3921.11.00.00 for cellular styrene polymer sheets used in shipping. Lightweight and shock-absorbent.
Styrene Foam Board for Model Making
High-density polystyrene foam boards used by hobbyists for architectural models and crafts. Meets 3921.11.00.00 as cellular sheets of styrene polymers per weight predominance rule. Easily cut and painted.
Cellular PS Diffusion Plates
Polystyrene foam sheets engineered as light diffusion panels for LED lighting fixtures. Under 3921.11.00.00 for cellular styrene sheets with light-scattering cellular structure. Used in commercial displays.
Polystyrene Foam Underlayment Sheets
EPS foam sheets used as flooring underlayment for sound and thermal insulation beneath laminate tiles. Classified 3921.11.00.00 as cellular styrene polymer plates. Moisture-resistant grade.