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ICC Updates Glass Codes
ICC Holds Its 2010 Final Action Hearings
By Megan Headley and Ellen Rogers
The International Code Council (ICC) held its final action code hearings
May 15-23 in Dallas, leading to several changes in how glass is labeled,
where it can be installed and other issues. The approved updates will
be released as part of the 2012 version of the International Codes, available
in April 2011, while some of those disapproved changes may return in the
next cycle of change proposals.
Fire-Rated Glazing Labels
Among the code changes that ICC approved during the hearings was a proposal
that mandates, among other things, how fire-rated glazing products are
to be marked (FS107).
The proposal is the result of research by ICC’s Code Technology Committee
(CTC) on the contentious topic of fire-rated glazing marking (see August
2008 USGlass, page 32, to learn more on the work leading up to this decision).
New to the section is table 715.3, which sets the procedure for marking
fire-rated glazing assemblies (see table below).
In their reasoning in favor of the proposed change, proponents Paul K.
Heilstedt, PE, FAIA, representing the CTC, and William F. O’Keeffe, representing
SAFTI FIRST, explained that the study group consisting of fire-rated glazing
manufacturers, code officials, architects and engineers agreed that the
existing markings were causing confusion. “It was recognized by the study
group that the existing marking system, as those marks were designated
in product listings, was leading to fire protection products in applications
not allowed by the IBC,” the code change proposal stated.
While the designations “W,” “OH,” “D,” “DT,” “DH” and “XXX” used to mark
fire-rated glazing remain as they were originally adopted in the 2004
code cycle, the marking of fire-rated glazing in fire door assemblies
(D) are simplified, according to the proponents, by deleting the NH designation
(not hose stream tested) and the NT designation (not temperature rise
tested). It is clarified that those designations correspond to test standards,
not end uses.
In addition, all text provision used to define and relate test standards
to marking designations were deleted in favor of including all of the
required marking provisions in table form. This change is intended to
provide code officials with easy access to the information needed when
inspecting installations, including required marking designations. In
connection with this change, several columns were added to tables 715.4
and 715.5. These additions specify the designations that officials will
need to look for when inspecting fire-rated glazing.
The size limitation provisions starting at 715.4.6.1 are re-written to
eliminate the use of “exception;” no substantive changes to these provisions
are intended. The proponents also determined that table 715.4 inadvertently
omitted reference to 1 1/2 hour doors in shaft, exit enclosures and exit
passageway walls and adds such a reference to the table.
The change proposal also stated that the marking provisions were written
to clarify “that fire protection rated glazing tested to NFPA 257 and
used in transoms and side lites in certain fire barriers and corridor
walls will also have to be tested to NFPA 252 since they are a part of
a door assembly. Accordingly, these glazings are marked D-H-OH-XXX.”
Thom Zaremba of Roetzel and Andress, representing glass manufacturers,
was a member of the CTC study group. “We found that there was a simple
solution … I believe FS107 represents a significant advance; where issues
previously existing among fire-rated glazing industry, they have all come
forward to support this,” Zaremba told the panel during the code hearings.
He also noted that this proposal had been unanimously recommended for
approval by the committee.
Modifying the Intersections
Also approved to the IBC’s Fire Safety section was a proposal that adds
a new exception to section 714.4 on curtainwall/floor intersections (FS88);
it was approved as modified. The code states currently:
Where fire resistance-rated floor or floor/ceiling assemblies are required,
voids created at the intersection of the exterior curtain wall assemblies
and such floor assemblies shall be sealed with an approved system to prevent
the interior spread of fire. Such systems shall be securely installed
and tested in accordance with ASTME 2307 to prevent the passage of flame
for the time period at least equal to the fire resistance rating of the
floor assembly and prevent the passage of heat and hot gases sufficient
to ignite cotton waste …
A proposal from James P. Stahl Jr., representing Specified Technologies
Inc., added an exception that introduces an additional standard, ASTM
E119:
Voids created at the intersection of the exterior curtain wall assemblies
and such floor assemblies where the vision glass extends to the finished
floor level shall be permitted to be sealed with an approved material
to prevent the interior spread of fire. Such material shall be securely
installed and capable of preventing the passage of flame and hot gases
sufficient to ignite cotton waste where subjected to ASTM E119 time-temperature
fire conditions under a minimum positive pressure differential of 0.01
inch (0.254 mm) of water column (2.5 Pa) for the time period at least
equal to the fire-resistance rating of the floor assembly.
Stahl says that the change reinstates an allowance that
was removed in the 2009 edition of the IBC.
Opponents of the proposal expressed concern during the hearing that allowances
should be made to a standard developed specifically for fire resistance
protection.
Maureen Traxler, representing the City of Seattle Department of Planning
and Development, requested disapproval of the change. In her comments
on the proposal, Traxler wrote, “The reason given for introducing the
exception is ‘there is a problem for certain types of assemblies in terms
of being able to meet the new performance criteria.’ In other words, the
assembly shouldn’t be required to be tested because it can’t pass the
test.”
Howard Hopper representing Underwriters Laboratories Inc., said that the
change indicates manufacturers can pass a test instead of complying with
the standard, but that no information was given about how to conduct that
test appropriately.
Traxler further noted, “Testing according to ASTM E 2307 is required because
there is a danger of fire lapping from floor to floor on the interior
side of curtainwalls. That danger is no less when glass extends to the
floor. This code change proposal should be disapproved because no technical
justification was provided to show why this construction should not be
required to comply with the ASTM standard.”
Despite concerns, that allowance will be reinstated.
The assembly heard other proposals regarding the intersection of exterior
curtainwall and floor assemblies. FS90, which ultimately was disapproved,
suggested requiring the materials used to seal the “void” between the
floor and exterior wall carry a fire rating.
Jesse Beitel, representing proponents representing Centria, Trespa North
America and Alcan Composites, explained during the hearing, “We have rated
walls meeting rated floors, that’s fine … the biggest problem we have
seen is a non-rated wall meeting a rated floor. How do you address that?”
As he pointed out, one side of the product sealing that intersection will
have no fire protection. “That’s what we were trying to clean up.”
Doug Evans, a fire protection engineer with Clark County, Nev., asked,
“Do I really need to maintain this to the level of the slab or of the
wall? If a non-rated wall fails and that stuff falls out, why is that
unexpected? Do I need to make the wall 2-hour
rated too?”
The proposed change won’t be seen in the upcoming International Codes.
Code Consistency
ICC also approved as submitted a proposal that removes an exception to
715.4.4.1 on glazing in doors and allows for the use of fire resistance-rated
glazing larger than 100 square inches in doors (FS100). The section, with
the change, will now state:
Fire-protection-rated glazing in excess of 100 sq inches (0.065 m2)
is not permitted. Fire resistance rated glazing in excess of 100 sq
inches (0.065 m2) shall be permitted in fire door assemblies when tested
as components of the door assemblies, and not as glass lights, and shall
have a maximum transmitted temperature rise of 450° F (250°
C) in accordance with 715.4.4.
O’Keeffe reasoned that the change “will make the size limits fire protection
glazing in 60- and 90-minute doors in exit enclosures and passageways
consistent with size limits for 60- and 90-minute doors elsewhere in
the code.”
The exception that was deleted had stated:
The maximum transmitted temperature end rise is not required in buildings
equipped throughout with an automatic sprinkler system installed in
accordance with Section 903.3.1.1 or 903.3.1.2.
“The presence of sprinklers in the building does not eliminate
the life safety and fire spread hazard posed by unrestricted transmission
of radiant heat flux through large sizes of fire protection rated glazing
panels in 60- and 90-minute doors, especially when those doors are protecting
exit enclosures and exit passageways deemed essential for occupant life
safety,” O’Keeffe said. The ICC apparently agreed.
O’Keeffe also proposed a modified change to the method of labeling fire-rated
glazing that ICC approved as submitted (FS101). The code addition states:
1703.5.4 Method of labeling. Information required to be permanently
identified on the product shall be acid etched, sand blasted, ceramic
fired, laser etched, embossed or of a type that, once applied, cannot
be removed without being destroyed.
O’Keeffe explained that the language for providing a method
of permanently identifying information required by the code on the label
was taken from Section 2403.1, which applies to the permanent identification
of information on glazing required by Chapter 24.
The assembly approved as modified by a comment a proposal that clarified
language in section 715.5 by changing references to glazing and fire windows
to “fire window assemblies” (FS102). O’Keeffe explained that this proposal
clarifies “that fire protection-rated window assemblies are subject to
area limits. Since there are some window assemblies that are fire resistance
rated to ASTM E119, this code change aids the user in clarifying that
fire protection rated window assemblies are subject to these limits.”
A Familiar Proposal
A proposal from SAFTI FIRST that would have permitted testing of a 20-minute
door assembly, including sidelites and transoms, to NFPA 252 without a
hose stream test when the assembly is in a half-hour rated corridor or
fire partition (FS97) was disapproved during the hearings.
According to O’Keeffe, the change proposal’s proponent, “Since a half-hour
wall tested to ASTM E119 is not required to be hose stream tested, there
is no fire safety reason to require the door assembly component in that
wall to meet a hose stream test.”
| “In an assembly that is not required to pass hose stream test there
should be no need for the transom and side lites to pass hose stream test,”
concurred Jeff Inks with the Window and Door Manufacturers Alliance.
O’Keeffe and other proponents of the change pointed to the lack of data
showing instances of failure of 20-minute products.
“There isn’t going to be any data because this simply isn’t the way it’s
been done,” Zaremba noted. He added that the issue had been overwhelmingly
voted down during the 2009 cycle.
Inks countered, “There is no data to show that there’s a need to require
the hose stream test for these 20-minute assemblies … Just because it’s
in the code doesn’t mean it’s justified to be there,” he added.
No Changes for Fire-Rating Corridors
ICC disapproved a proposed change to the IBC Means of Egress section that
would have mandated both automatic sprinklers and one-hour fire-rated
exit corridors be used in educational occupancies with fire areas greater
than 12,000 square feet (E113).
Educational occupancies with fire areas less than 12,000 square feet (typically
small, schools often in rural areas) are not required to include automatic
sprinkler systems, though 1-hour fire-rated exit corridors are required.
In fire areas exceeding 12,000 square feet, however, the code does require
the installation of automatic sprinklers, but the 1-hour fire-rated exit
corridor requirement is eliminated.
In disapproving the action, the committee reasoned that removing the trade-off
for sprinklers versus fire-rated corridors would result in many more schools
being designed without sprinklers. According to the committee:
Sprinklered schools are safer during a fire event than schools with
rated corridors. The antidotal data vs. the NFPA data does not justify
the significant increase in the cost of construction. In addition there
will be issues with maintaining the fire resistance rating of the walls
especially to automatic closers on the doors being in-place and functional.
The fire doors with automatic closers will be a problem for access to
classrooms. This would also require rated corridors in day care facilities,
which would be excessive …
The committee further noted that the change proponents continually
referred to the possibility of a fire event during a lockdown situation,
which led the committee to rule:
Rating of a corridor is a means of egress issue, not a security issue
… If there is a concern for a fire event during a lock-down that needs
to be addressed with the emergency responders in the fire and safety
evacuation plans, not through a corridor rating.
In addition, there are other safety concerns in schools. Schools commonly
have doors with vision panels and side lites for observation of the
classrooms and student/teacher interaction. Requiring rated doors at
these locations would either significantly raise the costs for the opening
protective and/or result in solid doors without this necessary observation
feature.
The code hearing committee likewise disapproved a proposal to require
Category III and IV buildings in hurricane prone and seismic areas to
include 1-hour fire resistance rated corridors (E114).
The code hearing committee reasoned:
Buildings in earthquake and hurricane areas are already designed to
a higher standard, therefore this rated corridor requirement is not
needed. Structural robustness is not related to fire-resistance-rated
corridors.
ICC OK’s Glass Doors in Atrium Walls
The IBC’s General Code section saw some changes as well; ICC approved
as amended a proposed change that clarifies that doors are allowed in
the glass wall forming the separation between an atrium and adjoining
spaces (G51).
Clay Aler, PE, of Koffel Associates, proposed adding to the exceptions
a provision that mandates how atrium spaces be separated from adjacent
spaces. The code requires a one-hour fire barrier constructed in accordance
with Section 707 or a horizontal assembly constructed in accordance with
Section 712, or both, be used in these areas. In areas where a glass wall
is used, Aler specified: “Self-closing glass doors shall be permitted
in the glass wall.”
In his comment, Aler wrote, “Where glass walls are used as an atrium enclosure,
it is typical to include glass doors in the glass walls to maintain material
continuity … The proposed revised text will make it clear that glass doors
are permitted in glass walls, so long as the glass doors are sprinkler
protected in a manner consistent with that provided for the glass wall.”
The exceptions to the section would now state:
1. A fire barrier is not required where a glass wall forming a smoke partition
is provided. The glass wall shall comply with all of the following:
1.1 Automatic sprinklers are provided along both sides of the separation
wall and doors, or on the room side only if there is not a walkway on
the atrium side. The sprinklers shall be located between 4 inches and
12 inches (102 mm and 305 mm) away from the glass and at intervals along
the glass not exceeding 6 feet (1829 mm). The sprinkler system shall be
designed so that the entire surface of the glass is wet upon activation
of the sprinkler system without obstruction;
1.2 The glass wall shall be installed in a gasketed frame in a manner
that the framing system deflects without breaking (loading) the glass
before the sprinkler system operates; and where glass doors are provided
in the glass wall, they shall be either self closing or automatic closing.
2. A fire barrier is not required where a glass block wall assembly, complying
with Section 2110 and having a 3/4-hour fire protection rating, is provided.
3. A fire barrier is not required between the atrium and the adjoining
spaces of any three floors of the atrium provided such spaces are accounted
for in the design of the smoke control system.
Megan Headley is the editor of and Ellen Rogers
is a contributing editor for USGlass.
USG
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