By Linda K. MonroeSince the first sun control window film was patented in 1966 by St. Paul, MN-based 3M Co., commercial building owners and facilities managers have relied upon window film to improve worker productivity through reduced glare and to lessen the damaging effects of the sun’s ultraviolet rays from fading carpet, upholstery, and furnishings. An added benefit of such films was a modicum of improved safety if the glass was broken. The industry soon realized, however, that specially developed safety/security films could protect occupants from violent weather, vandalism, and other breaks under impact as well. From thicker films with thicker adhesives to today’s micro-layering, the 25-year evolution in window films now provides facilities professionals with a technology that is truly cutting-edge.“We started out with single-layer films that were thicker and attached with stronger adhesives,” explains Jim Mannix, marketing manager at 3M Consumer Safety and Light Management Department, St. Paul, MN. “We learned over time, however, that layers make a difference. Instead of a 4-mil-thick product of straight 4-mil polyester, we evolved into a 2-plus-2 [mils each] laminated together, because we found those layers had enhanced impact-absorption qualities; there’s some give within the layers.“Today, our product takes another leap – in terms of 3M innovation – in our use of micro-layer technology. That same 4-mil film that used to be a single layer, and then two layers, is now 26 layers – essentially the same thickness but with significantly more tear and impact resistance. It meets a much higher standard.”Of particular interest to facilities professionals investigating the use of safety/security window film are three major premises, according to Mannix:• “First and foremost is life-safety,” he says, “protecting employees, the tenants, the people. That’s so important from a building owner/manager’s and risk manager’s perspective.• “Second is property protection. If a bomb goes off, you potentially could have fragments damaging a building’s interior, as well as the people in it.• “Third is continuity of operations – a major driver from a financial perspective. If a building goes down or you can’t access it for a few days [due to its adjacency to a targeted building], it could potentially cost a company millions of dollars in loss of operations.”Although safety/security window film is designed to make window glass more shatter-resistant, Mannix cautions professionals to avoid defining such film as hurricane-, earthquake-, bullet-, bomb-, or burglar-proof. In the event of a windstorm or earthquake, these films can reduce the risk of injury from flying shards of broken glass and possibly help prevent debris and water penetration or glass from falling out of a building. A particularly low-profile, high-performance measure of security against “smash and grab” crime, the tough, shatter-resistant qualities of safety/security film can hold window glass together – even if a brick or similar projectile actually passes through the glass. More attention is also being directed to full-building applications (vs. the more predominant first-floor retail applications of the past), based upon the knowledge of the types of glass breakage incidents that can occur.Linda K. Monroe ([email protected]) is editorial director at Buildings magazine.