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ESR-1308 | Most Widely Accepted and Trusted Page 6 of 21
<br />30-by-60-inch (762 by 1524 mm), 36-by-60-inch (914 by
<br />1524 mm) or 48-by- 48-inch (1219 mm) lay-in panels, two
<br />clips are placed over bulbs of each cross tee near cross tee
<br />quarter-points. One leg of each clip is cut off when
<br />placement is over bulbs of cross tees adjacent to the long
<br />side of light fixtures.
<br />4.7.8 Recessed Light Fixtures: Fluorescent-lamp-type,
<br />steel housing fixtures can be used in the fire-resistance-
<br />rated assembly, provided the fixtures measure 1 by 4 feet
<br />(305 by 1219 mm), 2 by 2 feet (610 by 610 mm), 2 by 4 feet
<br />(610 by 1219 mm), 20 by 48 inches (508 by 1219 mm) or 20
<br />by 60 inches (508 by 1524 mm). The nominally
<br />1-by-4-foot (305 by 1219 mm), 2-by-2-foot (610 by 610 mm)
<br />and 2-by-4-foot (610 by 1219 mm) fixtures may include
<br />vented sides for air boots and vented tops for air-return
<br />purposes. Linear air diffusers and linear air returns must be
<br />used with nominally 20-by-48-inch (508 by 1219 mm)
<br />fixtures. When nominally 20-by-60-inch (508 by 1524 mm)
<br />fixtures are used, fixture stabilizers are used to
<br />supplement the hanger wires occurring at the mid-span of
<br />the 5-foot-long (1524 mm) cross tees.
<br />When nominally 1-by-4-foot (305 by 1219 mm) fixtures are
<br />used, the aggregate number of fixtures must not exceed four
<br />per 100 square feet (9.3 m2) of ceiling area. When nominally
<br />2-by-2-foot (610 by 610 mm) fixtures are used, the
<br />aggregate number of fixtures must not exceed five per
<br />100 square feet (9.3 m2) of ceiling area. When nominally
<br />2-by-4-foot (610 by 1219 mm), 20-by-48-inch (508 by
<br />1219 mm), or 20-by-60-inch (508 by 1524 mm) fixtures are
<br />used, the aggregate number of fixtures must not exceed
<br />three per 100 square feet (9.3 m2) of ceiling area. The
<br />fixtures must be wired in conformance with an approved
<br />electrical code.
<br />The recessed light fixture must be protected on the topside
<br />with acoustical ceiling tile panel material having a minimum
<br />thickness of 5/8 inch (15.9 mm). The panels are cut into
<br />pieces to form a five-sided enclosure which is rectangular or
<br />trapezoidal in cross section, depending upon fixture type,
<br />and which is approximately 1/2 inch (12.7 mm) longer and
<br />wider than the fixture, with sufficient depth to provide at least
<br />1 inch (12.7 mm) of clearance between the fixture and the
<br />enclosure. The pieces are held together with 8d nails.
<br />Spacers provide the 11/4-inch (31.7 mm) clearances when
<br />placed on top of fixtures located away from the ballasts.
<br />When no air-handling or air-return fixtures are used, a
<br />maximum 11/4-inch (31.7 mm) separation must be
<br />maintained between the long fixture protection sidepieces
<br />and the top piece. When air supply light fixtures with air
<br />boots are used, fixtures and air boots must be fully enclosed
<br />except for the nominally 28-square-inch (18 064 mm2)
<br />opening needed for the connection to air-supply ducts.
<br />4.7.9 Air Duct: Air ducts are permitted in the assembly
<br />provided the ducts are constructed of minimum No.22 MSG
<br />galvanized steel and aggregate duct opening area is less
<br />than or equal to 113 square inches (72 903 mm2) per
<br />100 square feet (9.2 m2) of ceiling area. The maximum air
<br />duct-opening dimension is 12 inches (305 mm).
<br />4.8 8500 (Prelude SupraFine Fire Guard) Series One-
<br />hour Fire-resistance-rated Roof-ceiling System:
<br />This exposed grid system consists of the 8500 series main
<br />runners and the XL 8520 or XL 8540 cross runners, and is
<br />part of a one-hour fire-resistance-rated floor-ceiling system.
<br />The rating applies to restrained and unrestrained
<br />assemblies as described in ASTM E119. See Figure 6 for
<br />assembly details. General requirements in 2021, 2018,
<br />2015 and 2012 IBC Section 711 and 2009 IBC Section 712
<br />must be observed.
<br />4.9 Special Inspection:
<br />Where special inspections are required by the building
<br />official, the suspended ceilings in Seismic Design
<br />Categories C, D, E and F shall be subject to periodic special
<br />inspections during the installation of the suspended ceiling
<br />systems and their anchorage in accordance with the
<br />following requirements:
<br />• For installations in accordance with Section 4.4.2 of this
<br />report, special inspection must be conducted as required
<br />by the building official during enforcement of the 2021,
<br />2018 and 2015 IBC Sections 1704.5, 1705.1.1 and
<br />1705.13.2, 2012 IBC Sections 1705.1.1, 1705.11.4 and
<br />Item 3 of Section 1705.12; and 2009 IBC Section
<br />1704.15, Item 3 of Section 1708.1, and 1708.4, as
<br />applicable.
<br />• For installation in accordance with Section 4.4.1 of this
<br />report, special inspection must be in compliance with the
<br />following: Section 13.5.6.2.2 (h) of ASCE 7-05, and 2009
<br />IBC Section 1705.3.4, Item 3 for the 2009 IBC; Section
<br />13.5.6.2.2 (h) of ASCE 7-05, as applicable.
<br />• The special inspector must verify that the ceiling framing
<br />systems are as described in this report, and comply with
<br />this report and the approved construction documents.
<br />Where special inspections are required by the building
<br />official, a statement of special inspection must be provided
<br />as required by 2021, 2018, 2015 and 2012 IBC Section
<br />1704.3 (Sections 1705.2 and 1705.3 for the 2009 IBC).
<br />5.0 CONDITIONS OF USE
<br />The suspended ceiling systems described in this report
<br />comply with, or are suitable alternatives to what is specified
<br />in, those codes listed in Section 1.0 of this report, subject to
<br />the following conditions:
<br />5.1 The ceiling suspension main runners, cross runners,
<br />BERC, BERC-2,AL BERC-2, STAC and XTAC clips,
<br />and accessories must be fabricated and installed in
<br />accordance with this report and the manufacturer’s
<br />published installation instructions. In the event of a
<br />conflict between the manufacturer’s installation
<br />instructions and this report, this report governs.
<br />5.2 Design loads and spans of main and cross runners
<br />must comply with Tables 2 and 3 of this report.
<br />5.3 Suspended ceiling systems must be designed and
<br />installed in accordance with ASCE 7 Section 13.5.6 as
<br />referenced by the applicable IBC Section 1613. The
<br />documents must be prepared by a registered design
<br />professional where required by statutes of the
<br />jurisdiction in which the project is to be constructed.
<br />5.4 Special inspections must be provided in accordance
<br />with Section 4.9 of this report.
<br />5.5 For Seismic Design Category C, D, E or F, a quality
<br />assurance plan complying with IBC Chapter 17,
<br />including 2021, 2018, 2015 and 2012 IBC Section
<br />1704.3 (2009 IBC Sections 1705.2 and 1705.3) must
<br />be submitted to the code official.
<br />5.6 The ceiling framing systems must not be used to
<br />provide lateral support for walls or partitions, except as
<br />provided for in ASCE 7, Section 13.5.8.1 as referenced
<br />in the applicable IBC Section 1613.
<br />5.7 The ceiling systems must be braced to resist seismic
<br />forces as determined from Section 1613 of the IBC.
<br />5.8 The systems are limited to ceilings not considered
<br />accessible in accordance with Item 29 of 2021 IBC
<br />Table 1607.1, Item 28 of 2018, 2015 and 2012 IBC
<br />2130 E 17th St -
<br />10111279406/07/23
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