Not all sunglasses provide your eyes with the same amount of UV protection. Some trendy sunglasses are merely designed to look spectacular. Their primary function is not to protect your eyes, but to enhance your looks (or ego).
If you are here to understand everything about 100% UV protective sunglasses, you have come to the right place. We'll explain everything, from the UV-400 label, to protection against UV-A and UV-B radiation. And from Filter Categories to how to test if your sunglasses protect you against UV radiation.
Are expensive sunglasses better?
You might wonder if a pair of 400 Euro or $400 designer shades provide you the ultimate UV protection. You might be surprised, but an expensive pair of sunglasses is not necessarily better. It's not just the price you should look at to determine your sunglasses' UV protective qualities. Although it is true that most quality sunglasses meet the regulations, some expensive designer shades do not protect your eyes from all UV rays. How to know the difference you ask? We will explain it all right here.
UV filter in or on the sunglasses lens?
Most quality sunglasses that you can buy nowadays protect your eyes against 100% of UV-A and UV-B rays. UV protection of lower quality sunglasses come from a coating that is applied to the lens. High quality sunglasses have a UV filter embedded as a layer inside the lens. You cannot see it on the outside, but most reliable brands mention the UV protection clearly on their website or products. If it's not mentioned, chances are that they won't live up to your expectations.
Can you add UV protection to sunglasses
High quality lenses have the UV filter integrated inside the lens. If you would like to add UV filter to your existing spectacles it is technically possible but not recommended. There are special foils available that you can apply to the lens. But you can imagine that these often do more harm than good. I recommend you always buy quality sunglasses, which do not have to be expensive at all. And if you wear prescription glasses, you can choose to wear a sun cover, which is one of those oversized sunglasses that you wear over your spectacles.
How to test if sunglasses have UV protection
Buy a cheap UV light and shine it through the lens of your sunglasses onto a money bill, credit card or anything with a hidden UV mark. If you can see the hidden mark, then your sunglasses do not have UV protection.
You can also go to a highstreet optometrist who might have a fotometer. This is an instrument that measures the strength of certain types of electromagnetic radiation, including UV. He/she can test your sunglasses for you. Just know that you might walk away with a new pair once you set a foot in the door (just make sure this new pair does block all UV!)
The Meaning of the UV-400 label
Sunglasses that carry the UV-400 label provide you with almost 100% protection from harmful ultraviolet light rays. To put it more technical, they block wavelengths up to 400 nanometers. This includes the harmful UV-A and UV-B rays. There are also UV-C rays, but these do not have to be blocked by your sunglasses, because the earth's ozone layer or atmosphere absorbs these rays for you.
Sunglasses sticker or label UV-400
You know if a product shields your eyes from 100% UV rays when the website or product label clearly says one of the following:
- “100% protection against both UVA and UVB”
- “100% protection against UV 400"
- "UV-400 A/B"
If you are on holidays and find sunglasses in a gift shop indicating "Blocks UV", we recommend you walk away.
The meaning of Filter Category 3
Sunglasses with filter category 3 indication offer you high reduction of sun glare and good UV protection. They block to 100% of all UV-A and UV-B rays. So UV protection "category 3" sunglasses are probably what you're looking for when you're looking for high quality shades.
There is a Category 4, but it blocks too much light to be practical in use. For instance, you may not drive a car with Category 5 sunglasses. They should clearly indicate "MUST NOT BE WORN WHEN DRIVING". The more common, high quality indication of Category 3 only states "NOT SUITABLE WHEN DRIVING AT NIGHT".
Category 0, Category 1 and Category 2 sunglasses provide less protection and do not protect against all UV-A and UV-B rays.
Do sunglasses lose their UV protection?
Sunglass lenses do not suddenly lose their UV filtering abilities. Quality sunglasses have the UV filter integrated in the lens. So even scratches in the lens do not affect their UV filtering abilities.
However, if you buy a really cheap pairof sunglasses, chances are that the UV coating is simply applied on the outside of the lens. This means it's just a thin layer on the outside of the lens. When you wear these for a long time, the coating can dissolve and you end up with nothing more than colored glass.
There have been reports of sunglasses with mineral (glass) lenses that spontaneously lost their photochromatic abilities over time. These are a special type of lenses that color darker when there is more light around.
This concludes this article about 100% UV protection of sunglasses. You can rest assured that all BEINGBAR sunglasses are high quality. They have Category 3 lenses and bear the UV-400 label that indicates that they will filter out 100% of harmful UV-A and UV-B radiation. If you want to read more posts about high quality eco-friendly sunglasses, simply sign up in the side bar (or scroll down on your mobile). It's free and we normally only send you a few emails per month. Always on-topic and always highly informative. We post new articles several times a week.
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Warren MSc BA