Duct penetration of rated assembly - fire damper Duct penetration of a ceiling membrane of a floor/ceiling or roof ceiling assembly - radiation damper What about the penetration of the floor of a floor/ceiling assembly - how do I protect this?
Posts: 144 | Registered: Jun 2006
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The membranee being penetrated has to be protected....I.e. lower side of roof ceiling assembly..... The top section of the floor/ceiling assembly should be fire stopped around the metallic Ductwork.
This is in line with IMC 607.6- 607.6.2 Membrane penetrations. Ducts and air transfer openings constructed of approved materials, in accordance with Section 603, that penetrate the ceiling membrane of a fire-resistance-rated floor/ceiling or roof/ceiling assembly shall be protected with one of the following: 1. A shaft enclosure in accordance with Sections 707 of the International Building Code. 2. A listed ceiling radiation damper installed at the ceiling line where a duct penetrates the ceiling of a fire-resistance-rated floor/ceiling or roof/ceiling assembly. 3. A listed ceiling radiation damper installed at the ceiling line where a diffuser with no duct attached penetrates the ceiling of a fire-resistance-rated floor/ceiling or roof/ceiling assembly. 607.6.2.1 Ceiling radiation dampers. Ceiling radiation dampers shall be tested in accordance with UL 555C and installed in accordance with the manufacturer’s installation instructions and listing. Ceiling radiation dampers are not required where either of the following apply: 1. Tests in accordance withASTME119 have shown that ceiling radiation dampers are not necessary in order to maintain the fire-resistance rating of the assembly. 2. Where exhaust duct penetrations are protected in accordance with Section 712.4.2 of the International Building Code and the exhaust ducts are located within the cavity of a wall, and do not pass through another dwelling unit or tenant space.
-------------------- Can you build to minimum standards? FWIW - MCP, CBO, CPE, CI, CFPE, ASCET ********************************** ** www.notanicodesfan.org Posts: 4199 | From: Lost in the South........ | Registered: Apr 2004
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If the duct penetrates both the ceiling and the floor of the single assembly, then Fire Dampers (UL555) may be used if the damper is approved for installation in the floor type (i.e, wood, metal, or concrete)
If the duct only penetrates one portion or the other (either the ceiling or floor) but does not pass all the way through then a UL555C damper would be installed as approved by the specific assembly.
For example, an L528 floor/ceiling assembly is not allowed/approved to have any ductwork penetrations of a membrane and install a UL555C type damper. However, an L521 does have several approved ceiling dampers approved for use in that assembly.
-------------------- Kenneth Locke, CBO Chief Mechanical Inspector City of Tallahassee, FL Posts: 143 | From: Tallahassee, FL | Registered: Jan 2008
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