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SECTION
703 FIRE-RESISTANCE RATINGS AND FIRE TESTS
703.1
Scope. Materials prescribed herein for fire resistance
shall conform to the requirements of this chapter.
703.2
Fire-resistance ratings. The fire-resistance rating of
building elements shall be determined in accordance with the
test procedures set forth in ASTM E 119 or in accordance with
Section 703.3. Where materials, systems or devices that have
not been tested as part of a fire-resistance-rated assembly
are incorporated into the assembly, sufficient data shall
be made available to the building official to show that the
required fire-resistance rating is not reduced. Materials
and methods of construction used to protect joints and penetrations
in fire-resistance-rated building elements shall not reduce
the required fire-resistance rating.
Exception: In determining the fire-resistance rating of
exterior bearing walls, compliance with the ASTM E 119 criteria
for unexposed surface temperature rise and ignition of cotton
waste due to passage of flame or gases is required only for
a period of time corresponding to the required fire-resistance
rating of an exterior nonbearing wall with the same fire separation
distance, and in a building of the same group. When the fire-resistance
rating determined in accordance with this exception exceeds
the fire-resistance rating determined in accordance with ASTM
E 119, the fire exposure time period, water pressure, and
application duration criteria for the hose stream test of
ASTM E 119 shall be based upon the fire-resistance rating
determined in accordance with this exception.
703.2.1 Nonsymmetrical wall construction. Interior walls
and partitions of nonsymmetrical construction shall be tested
with both faces exposed to the furnace, and the assigned
fire-resistance rating shall be the shortest duration obtained
from the two tests conducted in compliance with ASTM E 119.
When evidence is furnished to show that the wall was tested
with the least fire-resistant side exposed to the furnace,
subject to acceptance of the building official, the wall
need not be subjected to tests from the opposite side (see
Section 704.5 for exterior walls).
703.2.2 Combustible components. Combustible aggregates
are permitted in gypsum and portland cement concrete mixtures
approved for fire-resistance-rated construction. Any approved
component material or admixture is permitted in assemblies
if the resulting tested assembly meets the fire-resistance
test requirements of this code.
703.2.3 Restrained classification. Fire-resistance-rated
assemblies tested under ASTM E 119 shall not be considered
to be restrained unless evidence satisfactory to the building
official is furnished by the registered design professional
showing that the construction qualifies for a restrained
classification in accordance with ASTM E 119. Restrained
construction shall be identified on the plans.
703.3
Alternative methods for determining fire resistance. The
application of any of the alternative methods listed in this
section shall be based on the fire exposure and acceptance
criteria specified in ASTM E 119. The required fire resistance
of a building element shall be permitted to be established
by any of the following methods or procedures:
1.Fire-resistance designs documented in approved sources.
2.Prescriptive designs of fire-resistance-rated building
elements as prescribed in Section 720.
3.Calculations in accordance
with Section 721.
4.Engineering analysis based on a comparison of building
element designs having fire-resistance ratings as determined
by the test procedures set forth in ASTM E 119.
5.Alternative protection methods
as allowed by Section 104.11.
703.4
Noncombustibility tests. The tests indicated in Sections
703.4.1 and 703.4.2 shall serve as criteria for acceptance
of building materials as set forth in
Sections 602.2, 602.3 and 602.4
in Type I, II, III and IV construction. The term "noncombustible"
does not apply to the flame spread characteristics of interior
finish or trim materials. A material shall not be classified
as a noncombustible building construction material if it is
subject to an increase in combustibility or flame spread beyond
the limitations herein established through the effects of
age, moisture or other atmospheric conditions.
703.4.1 Elementary materials. Materials required to
be noncombustible shall be tested in accordance with ASTM
E 136.
703.4.2
Composite materials. Materials having a structural
base of noncombustible material as determined in accordance
with Section 703.4.1 with a surfacing not more than 0.125
inch (3.18 mm) thick that has a flame spread index not greater
than 50 when tested in accordance with ASTM E 84 shall be
acceptable as noncombustible materials.
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