How do I read a fire-rated glass label?

As of the 2012 edition, the International Building Code requires fire-rated glazing to include a multifaceted product label code that building and design professionals can reference to quickly evaluate a product’s performance capabilities.

The first part of the label code is one or two letters that indicate which applicable test standard the glass has passed, and where it is considered suitable for use:

• “W” meets wall assembly criteria (ASTM E119 or UL 263)
• “OH” meets fire window assembly criteria including hose stream test (NFPA 257 or UL 9)
• “D” meets fire door assembly criteria (NFPA 252 or UL 10B or UL 10C)

The next two letters in the code sequence, if present, indicate conformance with certain test criteria:

• “H” meets fire door assembly “Hose Stream” test (NFPA 252 or UL 10B or UL 10C)
• “T” meets 450° F* temperature rise criteria for 30 minutes (NFPA 252 or UL 10B or UL 10C)
• “FC” meets floor/ceiling criteria (ASTM E119 or UL 263)

The last marking on the fire-rated glazing label is a two- or three-digit number that shows the fire rating in minutes (e.g., 45, 90, 120). The given number corresponds with independent lab testing in accordance with national fire test standards.

Putting all this together, a product labeled “D-H-T-60” and “OH-60” is suitable for use within door assemblies and openings, has passed the required hose stream test, does meet temperature rise criteria, and is fire-rated for 60 minutes.

For additional information and label samples, see our IBC Label Guide.

* For SI, °C = [(°F) -32]/1.8.
Source: 2015 IBC Table 716.3, Marking Fire-Rated Assemblies