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

2-8 Earthquake Protection
Page 34 FM Global Property Loss Prevention Data Sheets
Fig. 17. Examples of bracing attachments to piping
C. For multistory building risers where clearances meet the recommendations of Section 2.2.1.5.1, an
additional flexible coupling is needed at each floor level. Locate the flexible coupling within 1 ft (0.3 m)
of the floor (either above or below the floor; see Fig. 18). Where clearances per Section 2.2.1.5.1 are not
provided, install flexible couplings within 1 ft (0.3 m) above and below the floor. (Exception: the flexible
coupling below the floor should be located below any main supplying that floor.)
D. Flexible couplings are not needed beneath floors that rest directly on the ground; however, a flexible
coupling is needed above the ground floor as recommended in Sections 2.2.1.4.3(A) and 2.2.1.4.3(B).
E. Provide a flexible coupling within 2 ft (0.6 m) above or below any intermediate points of lateral restraint
for risers. Where welded piping systems exist from the riser through the crossmains, these flexible
couplings may be omitted.
2.2.1.4.4 Provide flexibility on feedmains and crossmains per the following recommendations.
A. Provide a flexible coupling within 2 ft (0.6 m) above or below intermediate points of lateral restraint
for vertical pipe. Where welded piping systems exist from the riser through the crossmains, these flexible
couplings may be omitted.
B. Provide flexible couplings within 2 ft (0.6 m) of the top and bottom of vertical pipe runs that are 6 ft
(1.8 m) or greater in length (in conjunction with the sway bracing recommended in Section 2.2.1.1.3[A]).
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 or spans between buildings.
D. Where clearances per Section 2.2.1.5.1 are not provided, install flexible couplings within 1 ft (0.3 m)
of each side of a wall. Where welded piping systems exist from the riser through the crossmains, these
flexible couplings may be omitted.
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