The code requirements for fire-rated door assemblies probably ranks as one of the most confusing areas of building codes. The revised Table 716.5 in the 2012 IBC (formerly Table 715.4 in the 2009 IBC) was a significant step in clarifying this confusion. For the first time, the code clearly laid out the vision panel size limits and added a column that specified the sidelite and transom rating requirements. These were not new changes, but a clarification of code requirements that were already in effect since the 2006 IBC.

The 2012 IBC did contain one significant update. In the 2006 and 2009 IBC, there was an exception in Section 715.4.4.1 that allowed fire-protective glazing to exceed 100 square inches in door vision panels in fire doors used in exit enclosures and passageways when the building was fully sprinklered in accordance with Section 903.3.1.1 or 903.3.1.2.

This exception was eliminated in the 2012 IBC (and in the 2015 IBC). With about 80 percent of the United States currently adopting the 2012 or 2015 IBC, the requirements in Table 716.5 is more important than ever. Below is an excerpt showing the door vision panel size requirements for 60- to 90-minute doors in exit enclosures and passageways:

Fire-protective glazing like ceramics and wire glass will always be limited to 100 square inches in door vision panels in fire doors used in exit enclosures and passageways, regardless if the building is sprinklered. However, footnote “c” in Table 716.5 allows the glazing panel to exceed 100 square inches if ASTM E-119-rated fire-resistive glazing is used (this is footnote “b” in the 2015 edition).

Most of the confusion can be traced to footnote “d” (or c in the 2015 edition), which references an exception in Section 716.5.5. To avoid specifying non-code-compliant 60- to 90-minute doors, it is important for architects to understand that the exception in 716.5.5 only applies to the door--not the glazing in the door. Even if the building is equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1 or 903.3.1.2., fire-protective glazing like ceramics or wire glass is still limited to 100 square inches in the door vision area.

Exit enclosures and passageways are critical areas that are necessary for the safe egress of building occupants, or as a haven where they can safely await rescue if egress is difficult or impossible. The 2012 and 2015 IBC language ensures that building occupants are always protected from dangerous radiant heat by limiting the amount of fire protective glazing used in the door vision panel regardless if the building is sprinklered.

For the states that are still in the 2006 and 2009 IBC, architects can protect building occupants from the uncontrolled passage of radiant heat by limiting fire-protective glazing to 100 square inches in the door vision panel regardless if the building is fully sprinklered.