49 CFR 173.221 - Polymeric beads, expandable and Plastic molding compound.
(a) Non-bulk shipments of Polymeric beads (or granules), expandable evolving flammable vapor and Plastic molding compound in dough, sheet or extruded rope form, evolving flammable vapor must be packed in: metal (4A, 4B, or 4N), wooden (4C1 or 4C2), plywood (4D), fiberboard (4G), reconstituted wood (4F), plastic (4H1 or 4H2) boxes, plywood drums (1D) or fiber drums (1G) with sealed inner plastic liners; in vapor tight metal or plastic drums (1A1, 1A2, 1B1, 1B2, 1N1, 1N2, 1H1 or 1H2); in vapor tight metal or plastic jerricans (3A1, 3A2, 3B1, 3B2, 3H1, or 3H2); or packed in non-specification packagings when transported in dedicated vehicles or freight containers. The packagings need not conform to the requirements for package testing in part 178 of this subchapter, but must be capable of containing any evolving gases from the contents during normal conditions of transportation.
(b) Bulk shipments of Polymeric beads (or granules), expandable, evolving flammable vapor or Plastic molding compounds in dough, sheet or extruded rope, evolving flammable vapor may be packed in non-specification bulk packagings. Except for transportation by highway and rail, bulk packagings must be capable of containing any gases evolving from the contents during normal conditions of transportation.