In conclusion, whether or not you need seismic braces for your cable trays depends on several factors, including local building codes, the importance of the cables being supported, application-specific needs, and advancements in seismic brace technology. Cable tray runs in seismic zones need more than normal hanger spacing. A standard trapeze support carries gravity load; it does not reliably stop lateral sway, longitudinal movement, anchor pullout, or cable spill during ground motion. A coordinated seismic bracing system uses strut channels. In areas with a high risk of seismic activity, the requirements for cable tray installations are often very strict. Threshold rules, longitudinal vs transverse bracing, MSS SP-58/SP-127 and SMACNA guidance, and the hospital-specific I_p = 1. Distribution systems — piping, ductwork, conduit. Recommendations are made for improvements in the design procedures for seismic bracing of nonstructural components. Why is seismic bracing important? International Building Code.
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