40 CFR § 441.20 - General definitions.
For purposes of this part:
(d) Dental amalgam means an alloy of elemental mercury and other metal(s) that is used in the practice of dentistry.
(e) Dental Discharger means a facility where the practice of dentistry is performed, including, but not limited to, institutions, permanent or temporary offices, clinics, home offices, and facilities owned and operated by Federal, state or local governments, that discharges wastewater to a publicly owned treatment works (POTW).
(h) Mobile unit means a specialized mobile self-contained van, trailer, or equipment used in providing dentistry services at multiple locations.
(i) New Sources means a dental discharger whose first discharge to a POTW occurs after July 14, 2017.