Safety of Polycarbonate Glasses

Safety glasses protect your eyes and head from potential injury while doing work or playing sports. The preferred material for safety lenses is polycarbonate, a type of plastic that is shatter-resistant. The American National Standard Institute (ANSI) sets certain standards and requirements for polycarbonate lenses and frames for safety glasses. Approved polycarbonate safety glasses will be marked with a stamp that says "Z87-2."

Material

• Eyeglass lenses are made from glass, plastic or polycarbonate. Glass is the heaviest type of lens and also the easiest to break. Plastic lenses are lighter than glass and do not break as easily. Plastic lenses are made by a slow heating and cooling process.

  Polycarbonate is lighter and thinner than plastic and is injection molded where tiny balls of plastic are rapidly heated, molded, compressed and cooled. The polycarbonate material is more pliable and will usually bend under stress instead of breaking like plastic or glass, making the material safer to wear in an industrial or sports situation.

Impact Resistance

• Polycarbonate is the best type of impact-resistant material for safety lenses, according to a study done by the Department of Ophthalmology and Visual Sciences, University of Louisville School of Medicine. However, no lens is shatter-proof. An advantage of polycarbonate material is that if it does break, it usually breaks into several large pieces unlike glass or plastic, which breaks into many tiny shards and is much more dangerous when broken.

Frames

• The best type of glasses for polycarbonate lenses are frames designed to hold safety lenses. Regular "dress" eyeglasses are not made like safety frames. During an impact, polycarbonate lenses can pop out of regular frames and potentially cause an injury. Polycarbonate safety glasses are available as a one-piece, non-prescription frame and lens set, usually sold in optical or sporting good stores. Safety frames are stamped with "Z87-2" to show that they meet ANSI standards of safety.

Fit

• A good fit is important with safety glasses. Opticians are trained to help you select the proper size of polycarbonate frames and will measure the front of your face and the temple length for the part that goes over your ears. Good fitting polycarbonate safety glasses are worn as close to your face as possible.

Care Items

• Clean polycarbonate safety glasses by washing with soapy water and drying with a soft cloth. Polycarbonate is softer than plastic and can scratch easier, even with a scratch-resistant coating. Replace lenses that have deep scratches, chips or cracks as this compromises the safety of the lenses.

Child Safety

• Polycarbonate is the only type of material recommended for children because of the safety of the lenses.

Ultraviolet Light and UV Quality of Polycarbonate

• Polycarbonate safety glasses have inherent ultraviolet protection, absorbing more than 99 percent of UV light. Wearing polycarbonate lenses protects your eyes from UV radiation, similar to sunscreen for your skin.