53 Pa. Stat. § 4633
Safe or special waste-pipes must not connect directly with any part of the plumbing system. Safe or special waste-pipe must discharge over an open, water supplied, publicly placed, ordinarily used sink, placed not more than three and one-half feet above the cellar floor.
The waste from a refrigerator, soda fountain, refrigerator case, or bar fixture must be trapped with suitable traps, and must not discharge upon the ground floor, but over an ordinary properly trapped, and vented water supplied sink, as above. In no case shall the special waste-pipes discharge over a sink located in a room used for living purposes.
The branches on vertical lines must be made by "Y" fittings, and be graded with as much pitch as possible. Where there is an offset on a waste-pipe, there must be clean-outs to control the horizontal part of the pipe.
In tenement- and lodging-houses the refrigerator waste-pipes must extend above the roof, and not be larger than one and one-half inches, nor the branches less than one and one-quarter inches. Lead safes must be graded, and neatly turned over beveled strips at their edges.
Fixtures or appliances drained by safe or special waste-pipes include such fixtures as soda fountains, refrigerators, refrigerator cases, bar fixtures, ice boxes, bottle coolers, steam tables, glass washers, rinsing sinks, bain maries, air conditioning units, sprinkler system drains, house-tanks, small or portable drinking fountains, coffee urns, and sterilizers.
53 P.S. § 4633