Forcible Entry Demonstrations
Page A-3
Air-blast Resistant Window Systems
Appendix A Terminology
Laminated Glass
Laminated glass, often referred to as safety glass, consists of multiple panes of glass
bonded together with an interlayer of polyvinyl butryl (PVB). This is similar to the glass
found in the windshields of automobiles.
Monolithic Glass
Monolithic glass is a single layer of glass without a laminate interlayer.
Plate Glass
See annealed glass
Polycarbonate
A plastic glazing material with enhanced resistance to ballistics or air-blast effects. This
material is not generally used unless windows are serving more than one purpose (i.e.
combined air-blast, forced entry and/or ballistics resistance). Polycarbonate windows
were not addressed during these demonstrations.
Safety Glass
See laminated glass
Security Film
Specially manufactured and tested film which is designed to remain adhered to glass
shards in the event of an explosive detonation, thus reducing the potential of penetrating
glass shard injuries to building occupants.
Security film is typically a layer of polyester, usually between 7 and 15- mil thick, applied
to the interior surface of windows. Security film can be installed in one of two basic
configurations: daylight applications or attached applications.
Structural Silicone Sealant
Structural silicone sealant is a specially designed silicone sealant with high strength and
adhesion characteristics. These products are used and tested in air-blast resistant
windows to enhance the connection between the window glass and the framing system.
Window systems which use structural silicone sealants may have smaller bites than those
window systems which do not.
Thermally Tempered Glass (TTG)
The manufacturing process for thermally tempered glass is identical to that for heat-
strengthened, the value for the surface compression is held at a very high quality.
Thermally tempered glass breaks into a multitude of small fragments of cube shape.
tempered glass is sometimes known as a safety glazing material.
Untreated Glass
Untreated glass is glass which does not have film or a laminate layer.