Wired glass was the only fire rated glass (FRG) product available for over 100 years. In traditional wired glass, the embedded wires hold annealed glass in place during the fire test to achieve a fire rating. While the wires give the illusion of increased strength and impact resistance, the opposite is true. Wired glass is not safety glazing. The wires actually weaken the glass, making it half as strong as ordinary window glass. Wired glass breaks easily on human impact, exposing razor sharp wires that can trap a victim’s limb in the opening and increase the severity of the injury. Alarmingly, wired glass is the most commonly used FRG product found in educational facilities, leading to over 2,500 wired glass impact injuries in schools every year. In 1977, the Consumer Product Safety Commission (CPSC) enacted a federal safety glazing standard (16 CFR 1201) to protect people from injury due to accidental impact with glazing. The building codes apply the CPSC standard to require that glazing used in hazardous locations, such as doors and sidelites, must meet minimum Category I and II impact standards, depending on the size of the glazing panel. Smaller glazing panels in sizes up to 1296 square inches must meet the Category I impact test of 150 ft. lbs. Larger glazing panels must meet the higher Category II standard impact test of 400 ft. lbs. of impact resistance. At the time the federal standard was enacted, wired glass manufacturers alleged they lacked the technology make a fire rated product that could meet the new CPSC standards. Since wired glass was the only FRG product available in 1977, the IBC granted wired glass a temporary exemption from meeting the CPSC standard. This exemption allowed wired glass used in fire assemblies to meet a lower ANSI Z97.1 impact standard of 100 ft. lbs., which the CPSC acknowledged was inadequate to protect anyone except children under five. For more information, click on the link below.
Related Stories
Cladding and Facade Systems | Oct 26, 2021
14 projects recognized by DOE for high-performance building envelope design
The inaugural class of DOE’s Better Buildings Building Envelope Campaign includes a medical office building that uses hybrid vacuum-insulated glass and a net-zero concrete-and-timber community center.
Fire-Rated Products | Oct 21, 2021
Safti First Fights Through Assertions Made By Plaintiffs Ely Holdings Limited And Greenlite Glass Systems That Safti First’s Fire Rated Floor System Infringed On Their Patent
In a summary judgement dated February 3, 2021, Chief Magistrate Joseph C. Spero of the United States District Court for the Northern District of California ruled that the patent infringement claims filed by Ely Holdings Limited (Ely) and Greenlite Glass Systems (Greenlite) against SAFTI FIRST, a USA fire rated glass and framing manufacturer, could not proceed to trial, finding that the SAFTI FIRST’s fire resistant floor does not violate Ely’s patent.
Sponsored | Glass and Glazing | Oct 1, 2021
Specifying Responsibly to Save Birds’ Lives
Realizing sustainable, bird-friendly glass design
Sponsored | Glass and Glazing | Oct 1, 2021
Seizing the Daylight with BIPV Glass
Glass has always been an idea generator. Now, it’s also a clean energy generator.
Glass and Glazing | Sep 30, 2021
Plans move forward on Central Place Sydney, duel towers with an AI-driven façade system
SOM and Fender Katsalidis are designing the project.
Glass and Glazing | Aug 24, 2021
Smart glass innovations for smarter buildings
Researchers explore the use of ultrathin photodetectors and augmented reality thin films to expand smart building applications.
75 Top Building Products | Dec 2, 2020
Top Glass and Glazing Products for 2020
Viracon's Thermal Spacer and YKK's YWW 50 TU Thermally Broken Window Wall are among the 7 new glass and glazing products to make Building Design + Construction's 2020 75 Top Products report.
Sponsored | Glass and Glazing | Nov 12, 2020
Fire Rated Glass Makes Visual Connectivity Possible, Beautiful and Affordable at Campus Housing
Sponsored | Glass and Glazing | Oct 20, 2020
Retaining Fallingwater’s Iconic Connection Between Indoors & Outdoors
Sponsored | Glass and Glazing | Sep 29, 2020
Glass helps Calgary Central Library convey collective and community