Polystyrene resin
Polystyrene resin means a thermoplastic polymer or copolymer comprised of at least 80 percent styrene or para-methylstyrene by weight.
Source
40 CFR § 63.1312
Scoping language
The following terms used in this subpart shall have the meaning given them in 63.2, 63.101, 63.111, 63.161, or the Act, as specified after each term:
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