An alternative material to polycarbonate is CR39 (Columbia Resin 39), a plastic polymer commonly used in the manufacture of eyeglass lenses. Unlike polycarbonate, CR39 requires a UV coating to be added to protect eyes from the sun’s harmful rays. A UV filter is extremely important, especially if you or your employees work outside.
Although commonly used by high street opticians in prescription safety eyewear, CR39 only offers increased robustness conforming to EN 166S similar to that of toughened glass. Many high street prescription safety lens ranges start with CR39 and only ‘upgrade’ to polycarbonate upon request. This is not common knowledge and many wearers assume they are protected just like their peers.