Anti dumping duty on polystyrene imports enforces trade remedy measures against specified exporters from select Asian countries. Anti dumping duties are imposed on High Impact Polystyrene (HIPS) and General Purpose Polystyrene (GPPS) originating in or exported from Hong Kong, Singapore and Thailand following the Designated Authority's findings of dumping and material injury; imports from China PR were treated as de minimis and excluded from duty recommendations, and duties apply from the date provisional measures were levied under the Customs Tariff Act and the anti dumping rules.