Process unit
Process unit means the equipment specified in the definitions of process unit in the applicable referencing subpart. If the referencing subpart does not define process unit, then for the purposes of this part, process unit means the equipment assembled and connected by pipes or ducts to process raw materials and to manufacture an intended product.
Source
40 CFR § 63.1020
Scoping language
All terms used in this part shall have the meaning given them in the Act and in this section.