Preventing glass from becoming a lethal weapon

Glass is attractive, lightweight, quick to install, provides light interiors, offers clean facades and is low in cost when compared to stone and other similar building materials. As a result, glass is used extensively in many commercial properties. However, in the event of an explosion, caused by an industrial accident or terrorism, this glass can cause serious injuries to a great number of people, and sadly many fatalities.

Laminated or tempered glass does not eliminate the danger as it shatters into bits that literally become small high-speed bullets. Also, the annealed glass in older buildings breaks into dagger-like shards, also travelling at speed. It is a recipe for disaster.

The 1995 Oklahoma City bombing in the USA illustrated this perfectly. Here the lethal combination of glass and a bomb projected shards at high speed causing 5 per cent of the deaths and 69 per cent of the injuries outside the buildings for a radius of over 10 blocks from the blast centre. 169 people lost their lives that day when glass in 258 buildings around the blast centre broke. Statistics reveal that bombs are a major terrorist threat with 69 per cent of attacks being bombings, 20 per cent are with firearms or blades and 11 per cent are through biological, gas or nuclear attacks.

Waiting for a similar incident to occur in Australia before taking measures is just not good risk management, especially as a proven cost-effective solution is available, which is very easy to install and could save both people and the post-event expenses relating to health care and litigation.

In Oklahoma, the AP Murrah building at the worst point received 62,000 Kpa and as glass breaks at half-psi blast pressure, and is lethal at 6 Kpa, the force of the blast is apparent. Most buildings cannot withstand higher blast pressures than 34 Kpa, so even a small blast can convert unprotected glass into high-speed projectiles.

In Australia, Bekaert Specialty Films supplies ArmorGard safety film - a film that had been installed at FBI headquarters and the Pentagon Building prior to September 11th where it proved itself. This catastrophic event prompted the US Government to revaluate the security in several other prominent buildings and they quickly placed an order with Bekaert to install their film on all windows of the US Capitol Building, the three House Office Buildings and the four Library of Congress Buildings; the most prestigious buildings in Washington DC.

As they wanted these installations completed as quickly as possible, some frantic activity ensued at the Bekaert manufacturing facility. Within 8 hours of receiving the order, all the lines were converted to production of the safety and security film with the total order being produced, inspected, slit and shipped to Washington within 72 hours. There a team of 50 installers, from all over America, was assembled and the entire job was completed within four weeks of the order placement. Today, most major US Government buildings in Washington have safety and security film installed as part of the effort to provide a safe environment and Bekaert is the largest supplier of these films to the US Government. ArmorGard films are made from extremely strong polyester that when adhered to the glass absorbs much of the force of an impact holding shattered glass within window frames, acting as a barrier between an explosion and victims. It has been independently tested in the USA and Australia by acknowledged testing organisations including the CSIRO, covering all aspects of performance including bomb blast tests, abrasion and longevity testing, and fire-related properties.

Specific ArmorGard films have passed the impact test requirements of AS/NZS 2208-1996, ASTM 1044-86 (resistance of plastic to scratch abrasion) and ASTM 1003-61 (haze and luminous transmittance of plastics). In addition to its high durability, ArmorGard also rejects 99 per cent of the UV light emitted by the sun so that it not only protects people, it protects curtains, carpets, furniture and valuable objects from fading.