How do I know my glasses will protect my eyes? Choose glasses that claim to block at least 99 percent of UV rays -- UVA as well as UVB. Look for a label reading "UV 400," since this designation means that the glasses block UV rays as small as 400 nanometers, providing 100 percent eye protection. Of course, you need to protect your eyes from the glare caused by the visible spectrum as well. To accomplish this, select products that block 75 to 90 percent of visible light.
What are polarized lenses? Polarized lenses are specially designed to filter out certain types of glare that tend to radiate upward from horizontal surfaces when sunlight bounces off these surfaces. They are recommended for tasks such as boating, fishing, skiing, golfing, jogging, and driving. Most polarized lenses will bear a label identifying them as such.