Bullet Proof Glass How Strong Is It?

Safety glass must be well made from quality materials. To measure the quality and toughness of this type of glass, there are industry standards that have to be met, and to do so, each glass product must be tested.
Both toughened and laminated safety glass has to meet a number of these standards, depending on their intended use. There are standards for the use of safety glass in architecture, transport, furniture, and more, each of which have a specific set of testing criteria to measure the product’s strength and functionality.

BS EN 12600

One important standard is BS EN 12600, which is used to test the strength of safety glass for use in buildings. The standard defines safety glass as glass which must have passed an impact test and either must not break or must break safely.

To meet this, safety glass must undergo an examination where a 50kg weight cushioned with two rubber tyres is swung at the sheet from three heights. Depending on which height the pendulum is at when the glass breaks and the type of breakage that occurs, the glass is awarded a three-character rating such as 3B2 or 3C1.


The first number represents the height class at which the pendulum was dropped from when the glass does not break or breaks safely into small fragments:

    A number 3 is awarded for a 190mm height, considered the equivalent of an adult pushing hard against the glass or a child running into it.
    A number 2 is awarded for a 450mm height, considered somewhere between an adult walking into and running into a glass door.
    A number 1 is awarded for a 1200mm height, considered a critical application, such as someone falling onto the surface.

The second letter represents the type of breakage mode:

    Type A represents a breakage with large, sharp fragments.
    Type B represents a breakage where the fragments are held together.
    Type C represents a breakage with small, harmless pieces

The third letter is awarded for the height class at which the glass does not break or allow penetration.

BS EN 12150

Although toughened glass for architecture has to meet the requirements for BS EN 12600 for use in buildings, it also has to meet its own standard of BS EN 12150, which covers the tolerance, flatness, edge-work, fragmentation, and physical and mechanical properties of thermally toughened safety glass. It should be noted that this standard does not apply to laminated safety glass.

Security glass

WHAT IS SECURITY GLASS?

Security glass shares many of the same qualities as safety glass. It is extra strong and will resist force more effectively than standard products, and it also shares the non-shatter safety features of laminated glass. Where security glass differs is in the specialised level of protection that it provides. It is tailor-made to combat certain threats, such as physical attacks, bullets, and blasts, with a design and materials that are chosen specifically to stand up to them.

The manufacturing of this type of product is not dissimilar to that of laminated glass, making use of layers to build strength and to maintain integrity. Security glass uses multiple panes of various thickness to deliver a product that will stand up to more extreme threats. As you move up through the levels of defence required, security glass can be built using thicker, stronger glass and with more layers to stand up to the anticipated impact.

This type of glass sees most use when something vulnerable needs defending or when a high-value item or high-ranking person needs to be safeguarded. Therefore, it likely that you will see security glass in locations like embassies, banks, jewellers, and petrol stations, or in vehicles like military trucks, executive cars, and cash-in-transit vans.