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What is UV400 Protection

What is UV400 Protection?

January 24, 2019

Who doesn’t love the glorious feel of a few rays of sunlight kissing your skin? And, compared to the leathery, Ooompa-Loompa look of sunbaked skin that was the norm in decades past, we’ve gotten a lot smarter about sun protection while enjoying the great outdoors or just running errands in the neighborhood. Everyone knows how important it is to slather on sunscreen, and clothing and hats with sun-protective features also have become more popular. So why aren’t we more careful about our eyes?

Maybe it’s because, unlike wrinkles and sunspots, we can’t see the damage the sun is doing to our eyes. A sunburn looks as painful as it feels, but UV light has to pass through your cornea to the retina and lens to inflict harm. The result? Cataracts, macular degeneration, and eye cancers that can lead to blindness—but don’t typically appear until your 40s or later. And since most sun exposure occurs before you turn 20, it may be too late by the time sunglasses become a regular part of your wardrobe. (But it never hurts to start!)

UV400 protection—which is to nearly 100 percent protection from harmful ultraviolet rays—can protect your precious peepers for a lifetime. Here’s everything you need to know about UV light—and how to choose the right specs with UV400 protection.


UV Light Defined

Ultraviolet, or UV light, is electromagnetic radiation from the sun. We can’t see it, but it penetrates the earth’s atmosphere and reaches your skin and eyes in the form of UVA and UVB waves. These harmful rays can do nasty damage in any season, and there’s no place on earth where you’re immune. Don’t think you’re safe in the shade, either: Wear those sunglasses on overcast days, too, since UV light is coming through even when the sun is hidden behind the clouds.


Total Protection

Investing in sunglasses that are labeled UV400 blocks 99 to 100 percent of UV light. This rating ensures that all light rays with wavelengths up to 400 nanometers, including both UVA and UVB rays, are blocked out. All of Knockaround’s stylish frames styles, from the timeless Premiums to the laid-back Paso Robles to our popular Limited Editions, carry the UV400 rating. The UV protection is built into the lens, so it won’t fade or disappear over time.


Who’s Most at Risk?

Because little ones are usually outside more often than adults, they’re considered high risk for UV damage to their eyes. Knockaround’s Kids Premiums are a solid (and affordable) investment in the future, with fun, downsized frames and sturdy, kid-proof construction that will stand up to just about anything your groms will throw at them. If you spend a lot of time on the water or in snow, those highly reflective surroundings also up your risk.

Finally, while road trips are an awesome way to kick back for some weekend chilling, car windows are another culprit, making UV400 sunglasses an essential piece of gear anytime you hit the road. Whatever adventure or action you have in mind, a pair of sturdy Fort Knocks will hold up.

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Sunburned Eyes

One eye condition that doesn’t take years of sun exposure to take hold is photokeratitis, which stems from excessive UV light exposure on the cornea. The effects aren’t pretty: pain, redness, blurriness, tearing, and the constant feeling of having sand in your eyes. You might also experience a headache, halos in your field of vision, and twitching eyelids.

Anyone who spends time in the snow and on the water is at risk, but hikers and climbers are even more prone to photokeratitis at altitude, where the thinner atmosphere means higher UV exposure. But fear not: You can easily stay protected in the outdoors with a pair of wrap-around or oversized sunglasses, like Knockaround’s Mile Highs.


UV, Tint, and Polarization

If you fall into one of the high risk groups—and that’s just about all of us at some point during the week—you’ll want to have a pair of sunglasses with polarized lenses at the ready. While polarization doesn’t block UV rays, it will cut down on reflected glare from water, snow, ice, sand, car windows, and even pavement. Polarizing lenses are an option on all of Knockaround’s best sellers and custom frames.

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UV and Blue Light Blocking

If you’re like us, you spend many of your daylight hours staring at digital screens. But did you know that the screen you’re looking at, whether it’s a computer, TV, or smartphone, emits a certain kind of blue light that can be damaging to your eyes? That’s why it’s essential to protect your eyes while you’re indoors, too, and Knockaround has just the solution with its specially designed Blue Light Blockers. These hardworking shades have a unique blue- or yellow-tinted lens that helps filter out damaging blue light from all of your screens. As a result, they help reduce digital eye strain, sleep disruption, and possibly the risk of macular degeneration.

Another bonus? Knockaround’s blue-light blockers also come with UV400 protection, which makes for a seamless transition to the outdoors. But they look so cool, with a wide range of colorways and style choices, including our Custom Premiums and Custom Fort Knocks styles, that you’ll have no problem wearing them inside while you knock out some work on your laptop or scroll through your Instagram feed on your smart phone.

Written by Jeff Banowetz for Knockaround

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