40 CFR 413.51: Specialized definitions.

For the purpose of this subpart;

(a) The term sq m (“sq ft”) shall mean the area processed expressed in square meters (square feet).

(b) The term operation shall mean any step in the coating process in which a basis material surface is acted upon by a process solution and which is followed by a rinse; plus the related operations of alkaline cleaning, acid pickle, and sealing, when each operation is followed by a rinse.