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SEISMIC BRACING NOTES <br /> HVAC DUCT AND MECHANICAL COMPONENTS (CONT'D) <br /> 4. Bracing for suspended components installed in-line with the duct system is not required <br /> where the operating weight is < 75 lbs. unless: <br /> a. The components convey, support or otherwise contain toxic, highly toxic or explosive <br /> substances, flammable gasses or are used for smoke control. (ASCE 7-10, Sec. <br /> 13.6.7) <br /> b. The component is a "Designated Seismic System" (Ip >1.0) (ASCE 7-10, Sec. <br /> 13.2.2) and is within or attached to a Risk Category IV structure. (ASCE 7-10, Sec. <br /> 13.1.3). The load path from the component to the structure is to be per the <br /> equipment seismic qualification and the manufacturer's instructions. Where such <br /> guidance does not exist for a Designated Seismic System, engineered restraints are <br /> to be provided. (ASCE 7-10, Sec. C13.6.5.5). <br /> 5. For Seismic Design Categories C thru F, seismic restraints are not required for duct <br /> components if the following conditions are met for the full length of the run: <br /> a. The duct is supported by hangers 12 in. or less in length from the duct support point <br /> to the overhead supporting structure. <br /> b. When rod hangers are used, they shall be equipped with swivels, eye nuts, or other <br /> devices to prevent inelastic bending in the rod. <br /> 6. Un-braced piping attached to in-line components shall be provided with flexible <br /> connections. <br /> 7. Where bracing is allowed to be omitted: <br /> a. Flexible connections are required between any fixed juncture or component and the <br /> connecting HVAC duct. <br /> b. Provisions are to be made to avoid impact with larger ducts or mechanical <br /> components or to protect the ducts in the event of impact. <br /> 8. All trapeze assemblies supporting ducts shall be braced considering the total weight of <br /> the duct(s) and insulation on the trapeze. If the actual weight of the duct is unknown, <br /> refer to Duct Weight Charts, Section X. <br /> International Seismic Application Technology <br /> 14848 Northam Street,La Mirada, CA 90638 <br /> 877-999-4728 (Toll Free) 714-523-0845(fax) <br /> www.isatsb.com <br /> askOtis Rev. 1 <br /> �Q� P 10/01/14 <br /> cc <br /> S 4710 n` <br /> 2;1: <br /> Page <br /> 9.2 <br /> *moo r9UCTUQ Qa`p <br /> Fop CavF° 2012/15 IBC <br />