DS 2-8 Earthquake Protection for Water-Based Fire ... - FM Global

Earthquake Protection 2-8
FM Global Property Loss Prevention Data Sheets Page 35
Fig. 18. Arrangement of flexible couplings for risers passing through floors of multistory buildings
2.2.1.4.5 Provide flexibility for in-rack sprinkler systems per the following guidelines.
A. Provide flexible couplings within 2 ft (0.6 m) of the top and bottom of each in-rack sprinkler system
riser, both in cases where the riser is attached directly to the ceiling sprinkler system riser (see Fig. 19),
and where the in-rack sprinkler system riser is attached directly to the underground piping. Details of
flexibility at the top of the riser may be the same as for sprinkler systems, as shown in Figure 1. Where
welded piping systems exist from the riser through the crossmains, the flexible coupling at the top of the
riser may be omitted.
B. Provide a flexible coupling within 2 ft (0.6 m) above or below intermediate points of lateral restraint of
the riser, or other vertical pipe. Except for pipe drops supplying in-rack sprinklers, where welded piping
systems exist from the riser through the crossmains, these flexible couplings may be omitted.
C. Provide a seismic separation assembly per Section 2.2.1.4.8 where any piping crosses a building
seismic expansion joint.
D. Provide a flexible coupling within 2 ft (0.6 m) of the connection of pipe drops to overhead piping or
armovers (see Fig. 20).
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