WINDOWS

Some fire doors are equipped with internal windows which also have a rating or have been incorporated at the time of the door test and be subject to the overall door's Product certification. Fire resistive windows must remain intact under fire conditions and hose stream impact resistance and can include:

• Wire mesh glass
• Liquid sodium silicate fills between two window panels
• Ceramic glasses
• Borosilicate glass

Wired glass typically with stands the fire, whereas the sodium silicate liquid also acts to insulate heat transfer due to endothermic action of this chemical.