53 Pa. Stat. § 14852
The term "private sewer" is applied to main sewers that are not constructed by and under the supervision of the department of public works.
The term "house sewer" is applied to that part of the main drain or sewer extending from a point five feet outside of the outer wall of a building, vault, or area to its connection with public sewer, private sewer, or cesspool.
The term "house drain" is applied to that part of the main horizontal drain and its branches inside the walls of the building, vault or area, and extending to and connecting with the house sewer.
The term "soil-pipe" is applied to any vertical line of pipe extending through the roof, receiving the discharge of one or more water-closets, with or without other fixtures.
The term "waste-pipe" is applied to any pipe extending through roof, receiving the discharge from any fixtures except water-closets.
The term "vent-pipe" is applied to any special pipe provided to ventilate the system of piping, and to prevent trap siphonage and back pressure.
53 P.S. § 14852