Flame-Retardant PS Foam Sheets from United States
Flame-retardant PS foam sheets are cellular polystyrene sheets chemically modified with fire-resistant additives for building and construction applications. They are classified under tariff item 3921.11.00 as cellular plates and sheets of polymers of styrene, as the chemical modification does not change the base polymer classification per subheading note 1(c).
Duty Rate — United States → Canada
0%
Import Tips
• Provide documentation on the flame-retardant additives and confirm the polystyrene content is 95% or more by weight to meet subheading note 1(a)(1)
• Ensure the sheets are imported as raw sheets, not as building components, to stay under 3921.11.00
• Check if the flame-retardant treatment constitutes a 'composition' per supplementary note 2, which may affect classification