Tempered glass used in tall buildings can break and fall out during a fire, changing how the fire spreads. Researchers heated tempered glass panels to study when they break and fall out. They found that for 6 mm-thick tempered glass, it will likely break and fall out at a temperature difference of 301 °C and a heat flux of 36.17 kW/m2. This information can help design safer glass facades for buildings during fires.