Piping should be supported to ensure alignment and to prevent sagging. Piping in the ground should be laid on a
proper bed. Piping above ground should be supported with hooks, straps, bands, brackets and/or hangers suitable for
the size of the piping, of adequate strength and quality, and located at intervals so as to prevent sagging, damage
and vibration. Other piping should not support piping. Piping should not put strain upon connected equipment or
appliances.
Hangers and strapping should be of approved material that will not promote galvanic action. Rigid-support
sway-bracing should be installed at changes in direction greater than 45° (0.79 rad) for pipe sizes 4 inches and
larger. Piping should be supported at distances not to exceed those in Table 11.1. For large pipes, hangers alone
may not be sufficient to resist the forces created by water movement inside the pipes, and rigid bracing may be
needed. Vertical piping typically needs support only at each story height.
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