Md. Code, Pub. Util. § 25-401

(a) In this subtitle the following words have the meanings indicated. (b) “Apartment unit” means a single family housing unit that: (1) is one of multiple units within a building; (2) contains at least one full bath and one full kitchen; and (3) does not contain more than two toilets. (c) “Fixture unit” means the assigned value for a plumbing fixture or group of plumbing fixtures, as set forth in the Commission’s plumbing and gas fitting regulations, that is standardized with a common lavatory having an assigned value of one based on its probable discharge into the drainage system or hydraulic demand on the water supply. (d) “New service” means: (1) a first time connection of a property to the Commission water or sewer system, including: (i) a direct connection of an improvement or building; or (ii) a connection of the improvement or building through an existing on–site system; or (2) a new connection or increased water meter size for a property previously or currently served by the Commission if the new connection or increased meter size is needed because of a change in the use of the property or an increase in demand for service at the property. (e) “Property” means an improvement or a building on a lot or parcel of land that contains plumbing fixtures. (f) “Toilet” means a water closet, as set forth in the Commission’s plumbing and gas fitting regulations.