(a) Plant means the land, buildings, surroundings, facilities, and equipment, whether owned or operated by one or more persons, constituting a single operating unit or establishment for the receiving, handling, or processing of milk or milk products as determined by the market administrator.

(b) Pool plant means any plant which is designated as a pool plant pursuant to sections 20.24 to 20.28 of this Part and any plant, except another order plant, which receives no milk from dairy farmers or units and from which 50 percent or more of the gross receipts of skim milk and butterfat in the form of fluid milk products is disposed of in consumer packages or dispenser inserts in the marketing area by direct distribution or is moved either in packaged form or bulk to other plants in the marketing area.

(c) Partial pool plant means a plant which is so designated pursuant to section 20.29 of this Part.

(d) Other order plant means a plant which is fully subject to the pricing and payment provisions of another order.