UV400 Protection and Filter Categories Of Sunglasses

​​What to Look For When Protecting Your Eyes From UV Damage

Imagine you head down to the beach and unfurl that new parasol you bought recently. It was expensive, but not only does it look great, the shop assistant also promised “epic sun protection”. You’re not sure how sun protection can be epic, but hey, you’re a sucker for this kind of salesmanship. Except when you unfurl the thing it’s got holes in the canopy like a slice of Swiss cheese, allowing the blazing sun to pour through, and offering zero protection against the sun.

​Sunglasses filter quality questions

You’re a sucker all right, and now you’d want your money back, and you’d definitely want a better parasol. Now, for hats, caps, and parasols, it’s pretty easy to see if the specs don’t measure up - for one thing gaping holes are much easier to spot, and for another, when you don’t have effective skin protection, sunburn is pretty obvious, not to mention painful. When it comes to your eyes however, the picture isn’t necessarily so clear.

How much protection from your sunnies?

For a start, it’s difficult to tell just on the basis of looking at a pair of sunglasses how much protection they offer against ultraviolet light. Lens colour and shade on the face of it has little to do with the UV shielding effect. Secondly, the damage done to your eyes is not as immediate or clear as something like sunburn - it happens over the long-term, and is far more subtle.

Our eyes need protection from the sun’s harmful ultraviolet rays, since overexposure can severely deteriorate eye-health. If you’re not careful, you could pick up any number of eye conditions ranging from retinal-tissue damage to cataracts amongst other things.

Sunglasses labeling and filter categories

Luckily there’s plenty of labelling in the sunglasses world today to help you identify the level of protection you’ve got from the nasty effects of those UV rays. So, we’re going to delve into what to look for in your next pair of sunnies so that you get the protection you need - before that, let’s do a quick session in UV Light 101 so that you understand what you’re protecting yourself from.

The UV Light Spectrum

There are three types of UV light out there.

• UVC: this is very damaging to the skin, but fortunately most of it is absorbed by the ozone layer (remember to limit your CFC’s people).
• UVB: these type of rays affect your outer skin and lead to sunburn. They can also harm your corneas, causing irritation and adverse sensitivity to light.
• UVA: whilst not necessarily being as “strong” a light as UVB, this is more prevalent, and so penetrates deeper. Of all the UV radiation that you are exposed to, UVA makes up 95% of it. It causes tanning and aging of the skin - however, it also impacts the inner layers of the eyes and the retinas.

What Protection Do I Need?

Another aspect of UV rays to mention is that they have different wavelengths, ranging from 100 nanometers (nm) to 400 nm:

UV400 protection sunglasses

​What this means is that in order to block ​your eyes from UVB rays for example, your sunglasses would need adequate protection up to UV 315. As you can see from the potential harmful effects of all UV rays, what is best is a sunglass lens that protects from all ultraviolet rays. This is why it’s so important to purchase sunglasses with “UV400 protection”, as no UV rays will directly enter your eyes from the front. Of course with thin frames and narrow lenses UV rays can intrude from the sides, so it is perhaps good to look for wider frames and broader lenses.

What to Look For in UV protection

Most sunglasses will have their UV ratings either labelled on the packaging or embedded into the lens. Look for labelling that either says “100% protection against both UVA and UVB” or “100% protection against UV 400”.

There’s a misconception that as long as the shades of your sunglasses are pretty dark, that will be sufficient protection against the UVB’s and UVA’s, and indeed whilst older vintage sunglasses might look cool, most will not offer effective UV protection.

What Are Filter Categories for Sunglasses?

Sunglasses have different levels of glare absorption, i.e. how dark the lens is, and it’s ability to leave your vision unimpaired in certain lighting conditions. in the EU these are designated by separate Filter Categories. Do note, that this has nothing to do with UV protection, but rather about your physical ability to see in the relevant conditions. The lenses absorb varying levels of light, and have five distinct categories ranging from 0 - 4.