(1) Except as provided in Sentence (2), a saddle hub or fitting shall not be installed in drainage systems, venting systems or water systems.
(2) A saddle hub or saddle clamp may be installed in a building drain or building sewer of nominal diameter not less than 8 in. and that is in service provided that the connecting branch is at least two pipe sizes smaller than the run of the building drain or building sewer to which it is connected.