Pennsylvania Statutes Title 53 P.S. Municipal and Quasi-Municipal Corporations § 4625. Changes in direction

All sewer, soil and waste pipes must be as direct as possible.  Changes in direction must be made with fittings, “Y's”, combination Y and eighth bends, or half “Y's”, or one-eighth bends.  Offsets in soil or waste pipes will not be permitted when they can be avoided;  nor, in any case, unless suitable provision is made to prevent accumulation of rust or other obstruction.  Offsets shall be made with forty-five degree bends, or similar fittings.  The use of T's or sanitary T's will be permitted on upright lines only.  Saddle hubs when bolted or strapped on are prohibited.