Mitigation Reduces Glass Hazards
Hi-Tech Security Films Protect Businesses and Residences

By Virginia L. Kubler

Security film, a highly sophisticated, laminated film of polyester and metallized coatings bonded by a unique adhesive system can drastically reduce damage and injury due to natural and manmade disasters. The use of glass as a construction material has grown dramatically. Glass is often the first line of impact, yet it is often ignored in vulnerability assessments by security, safety or risk management personnel.

INCREASED GLASS USAGE INCREASES RISK

The growth of glass usage in commercial buildings has been impressive as office towers of glass and steel now dominate cities. Protection from broken glass and flying fragments is accordingly a growing concern. The increased use of glass in buildings and homes and more frequent incidents of turbulent weather, earthquakes, civil disturbances and acts of terrorism have heightened the risk of personal injuries from broken glass and severe damage to furnishings, electrical components and computer networks.

TYPES OF STRESS WHICH MAY CAUSE GLASS BREAKAGE

Glass breaks when stressed. There are five types of stress, which may cause glass breakage.

1. Thermal Stress – from absorption of solar radiation
2. Tensile Stress – from the weight of the glass itself
3. Mechanical Flexing Stress – from wind, earthquakes, etc.
4. Impact Stress – from flying objects, hail, baseballs
5. Twisting Stress – from building or window frame sagging, settling or earthquakes

MITIGATION REDUCES GLASS HAZARDS

Hurricanes and earthquakes are the natural disasters causing the most glass breakage. Hurricane winds and rain coupled with flying debris pose a particularly serious glass breakage threat. Security window films, sometimes referred to as fragment-retention films, are designed to help resist the force of wind and rain and to help hold shattered glass together. In the event that a film-protected window is broken, the ability of the film to hold glass fragments together helps maintain the building envelope and reduce interior damage.

Beyond fragment retention, security films, which come in a wide variety of constructions and thickness, provide many additional cost savings and practical features. These include energy savings through the control of heat loss and gain, protection from harmful ultra-violet radiation, prevention of heat build up and harsh glare associated with uncontrolled sunlight and safeguards against fading of furnishings. Security films are usually professionally installed as a retrofit product directly to the interior side of the glass.

CASE STUDY

Consider an incident in a terrorist bombing in London. A nearby building, the Union Insurance Place building, which had been protected with safety film, was virtually undisturbed. Only fifty of the nearly one thousand windowpanes cracked, with the glass being held in place by safety film. Other buildings in the area with unprotected glass suffered badly, with over 500 tons of shattered glass, glass shards and other debris removed from the bombed area. Most importantly, electrical and computer components were protected from fire hose water as the envelope of the building was maintained.

Clearly protection against window breakage and the ravages of shattered glass belongs in any building safety audit, with security (fragment retention) films having an important role in today’s risk manager’s portfolio.

About the Author
Virginia L Kubler is Director of Sales and Marketing-Window Films, CPFilms Inc., the largest producer of solar control and security films in the world. For more information on this topic, please call (800) 255-8627 or visit the web-site at www.llumar.com.