Understanding Multi-layered Security Laminates
For the intent of this discussion safety and security will be classified in to categories:
- safety involves reducing the risk of injury, loss of death due to accidental, natural and or unintentional causes;
- security involves reducing risk of injury, loss or death due to the intentional actions of another person or action taken by a group.
Safety Films
Safety films contain a single sheet of polyester with either a pressure-sensitive or water-activated acrylic adhesive. They are a spin-off solar control films and are generally 02, 04, 4.5, 05, 06, 07, 08 mils (0.002 to 0.008 inches) in normal thickness. Safety films are available in clear, solar control reflective or architecturally tinted varieties. Some have ultraviolet (UV) protection.
Safety films are essentially used to protect against light load-bearing effects that would ordinarily crack, shatter or break glass. Most have poor adhesive capabilities because their adhesives harden and dry completely and are of minimal thickness; these safety films (or tints) are most likely to suffer "delamination" (i.e, the film separating, bubbling or peeling away from the glass).
Improper cleaning methods can scratch or deface poor quality safety films. In addition, safety films do not have a strong resistance to chemicals; as a cautionary note, some manufacturers recommend not using ammonia based cleaner on films.
The standard used for the testing of safety films in ANSI Z 97. 1-1984. This testing has performance criteria that are directly related to the reduction of cutting and piercing injuries to persons who impact the glazing. It should be noted that this test is centered on preventing harm to and individual impacting the coated glass. It is not designed around objects, explosions or projectiles impacting the glass, nor does it measure how well the glazing stays intact or prevents the glass from separating and impacting, cutting or piercing those behind it. The three impact levels for ANSI Z 97. 1-1984 are 100, 150 and 400 foot-pounds (ft-lbs). Nearly all safety films can pass the 100 and 150 ft-lb impact testing requirements without a substantial percentage of glass loss. Moreover, very few pass the 400 ft-lbs test. |
