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UV Protection Sunglasses - How Different Protection Categories Work

Many people use sunglasses as a fashion accessory to add a touch of sophistication to their style during the spring and summer months. However, not everyone is aware that UV sunglasses have a very practical purpose in addition to being fashionable. 


The lenses protect your eyes from harmful UV rays, which are problematic on both clear and cloudy days. When we are exposed to the sun, our eye pupils constrict to filter the light before it hits our retina. When the UV rays are very strong, this natural filter isn't enough and could lead to eye health issues. To prevent various issues, you can wear sunglasses that provide UV protection.

UV Protection: How are your Sunglasses protecting your eyes from the sun? | 2018 Q&A

What is the best UV category for sunglasses?

People's eyewear needs vary, so it's only natural that sunglasses come with a variety of lenses to accommodate various conditions and environments. The lenses usually fall into one of five levels that offer different protection.


Let’s explore the UV filter sunglasses categories:

  • Category 0 blocks out only 3-20% of UV rays, so they aren't a viable option for eye protection. Fashion lenses or softly coloured tints are most often in category 0 UV sunglasses.


  • Category 1 blocks 20-57% of UV light, which are also usually fashion lenses. Category 1 sunglass lenses are best suited for foggy days with little sun exposure.


  • Category 2 lenses block 57-82% of UV rays and are appropriate for partly overcast days. UV sunglasses with lens category 2 are typically lighter in colour than others.


  • Category 3 lenses block 82-92% of UV light, which makes these UV sunglasses an excellent choice for sun protection.


  • Category 4 lenses are the highest category available, blocking 92-97% of UV rays to provide maximum protection. Sunglasses with lens category 4 are ideal to use in exceptionally bright settings, such as at high elevations or sea. However, it is important to note that they are not suitable for driving due to the dark lens tint.    

How to tell if sunglasses have UV protection

UV protection sunglasses filter the sun's harmful rays by absorbing UV radiation through the lens material or coating. Unfortunately, simply looking at your sunglasses will not reveal whether or not they feature UV-protective lenses. You can't look at the lens colour to determine how much  UV protection you're getting, because lens tints have nothing to do with UV protection. 


An eye care specialist can use a photometer to evaluate your UV protection sunglasses in a matter of seconds to tell you how effectively they protect your eyes. When buying sunglasses, you should check the labels and examine the frame for markings that indicate the lens category.


European sunglasses such as Gucci and Dior have the “CE” mark, which indicates that they pass EU regulations and are suitable for use in most situations. It's derived from the French ”Conformite Europeene,” which means conformity to European law.

What is the difference between UV protection and polarized sunglasses?

While UV protection sunglasses are designed to protect your eyes, polarized sunglasses are designed to reduce glare so you can see more clearly without squinting. People who play video games, water sports, or are bothered by glare daily choose these lenses. 


Although polarization has nothing to do with UV light absorption, many polarized lenses now have a UV-blocking material added to them. Older sunglasses with scratches on the coatings will not provide as much protection as newer UV protection sunglasses, so it is important to take care of them to ensure they protect your eyes. Keep in mind that UV protection is the most critical characteristic to look for and should be your top priority when buying glasses.