SECTION
709 SMOKE BARRIERS
709.1
General. Smoke barriers shall comply with this section.
709.2
Materials. Smoke barriers shall be of materials permitted
by the building type of construction.
709.3
Fire-resistance rating. A 1-hour fire-resistance rating
is required for smoke barriers.
Exception:
Smoke barriers constructed of minimum 0.10-inch-thick (2.5
mm) steel in Group 1-3 buildings.
709.4
Continuity. Smoke barriers shall form an effective membrane
continuous from outside wall to outside wall and from
the top of the foundation or floor/ceiling assembly below
to the underside of the floor or roof sheathing, deck or slab
above, including continuity through concealed spaces, such
as those found above suspended ceilings, and interstitial
structural and mechanical spaces. The supporting construction
shall be protected to afford the required fire-resistance
rating of the wall or floor supported in buildings of other
than Type lIB, IIIB or VB construction.
Exception:
Smoke-barrier walls are not required in interstitial spaces
where such spaces are designed and constructed with ceilings
that provide resistance to the passage of fire and smoke equivalent
to that provided by the smoke barrier walls.
709.5
Openings. Openings in a smoke barrier shall be protected
in accordance with Section 715.
Exception:
In Group 1-2, where doors are installed across corridors,
a pair of opposite-swinging doors without a center mullion
shall be installed having vision panels with fire-protection-rated
glazing materials in fire-protection-rated frames, the area
of which shall not exceed that tested. The doors shall be
close fitting within operational tolerances, and shall not
have undercuts, louvers or grilles. The doors shall
have head and jamb stops, astragals or rabbets at meeting
edges and shall be automatic closing by smoke detection in
accordance with Section 715.4.7.3.
Positive-latching devices are not required.
709.6
Penetrations. Penetrations of smoke barriers shall comply
with Section 712.
709.7
Joints. Joints made in or between smoke barriers shall
comply with Section 713.
709.8
Ducts and air transfer openings. Penetrations in a smoke
barrier by ducts and air transfer openings shall comply with
Section 716.
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