What are the size limits for fire-rated glass used in 60 and 90 minute door assemblies?
A recently finalized revision to the IBC model building code limits the size of fire protective glazing,
such as safety wired glass and safety ceramic, used within vision
panels for 60 or 90 minute temperature-rise doors to no more than 100
square inches, whether or not sprinklers are present. To increase
the amount of fire-rated glass in 60 or 90 minute temperature-rise doors
and still meet code, you must use fire resistive glazing
that meets ASTM E119. Furthermore, sidelights and transoms placed
in a 1 or 2 hour wall and door assembly in a shaft, exit enclosure, or
exit passageway must also be fire resistive glazing.
The new code clears up confusion that has existed since IBC 2000 when an exception for fire resistive glazing in temperature-rise doors was inadvertently duplicated for fire protective glazing. This change is important because neither sprinklers nor fire protective glazing can protect life safety or stop the spread of fire caused by the unrestricted transmission of radiant heat.
Table
715.4 in the IBC 2012 model code addressing fire door assembly rating
requirements has also been revised to spell out the test and rating
requirements for fire protective and fire resistive glazing in doors,
side lights and transoms. Click here to download a pdf of the 2012 IBC 715 tables.
The
expanded tables in the 2012 IBC now include the requirements for
sidelights and transoms previously specified in Section 715.4.5 of 2009
IBC, which states:
"Door
frames with transom lights, sidelights or both, shall be permitted
where a ¾-hour fire protection rating or less is required... Where
a fire protection rating exceeding ¾-hour is required in accordance
with Table 715.4, fire door frames with transom lights, sidelights, or
both, shall be permitted where installed with fire resistance rated
glazing tested as an assembly in accordance with ASTM E119 or UL
263."
These
requirements are not new. They conform to what NFPA 80 has long
provided in the 1999 and 2007 NFPA 80 editions, which are incorporated
by reference into the new IBC codes.
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