Section 3280.608 - Hangers and supports(a)Strains and stresses. Piping in a plumbing system shall be installed without undue strains and stresses, and provision shall be made for expansion, contraction, and structural settlement.(b)Piping supports. Piping must be secured at sufficiently close intervals to keep the pipe in alignment and carry the weight of the pipe and contents. Unless otherwise stated in the standards incorporated by reference for specific materials at § 3280.604(a) , or unless specified by the pipe manufacturer, horizontal plastic drainage piping must be supported at intervals not to exceed 4 feet and horizontal plastic water piping must be supported at intervals not to exceed 3 feet. Vertical drainage and water piping must be supported at each story height.(c)Hangers and anchors.(1) Hangers and anchors shall be of sufficient strength to support their proportional share of the pipe alignments and prevent rattling.(2) Piping shall be securely attached to the structure by hangers, clamps, or brackets which provide protection against motion, vibration, road shock, or torque in the chassis.(3) Hangers and straps supporting plastic pipe shall not compress, distort, cut or abrade the piping and shall allow free movement of the pipe.40 FR 58752, Dec. 18, 1975, as amended at 86 FR 2521 , Jan. 12, 2021