If the sun doesn't bother my eyes, do I still need to wear sunglasses?
Yes. The sun has damaging UV rays that can cause photokeratitis, pinguecula, and permanent retinal damage.
What exactly are UV rays?
Ultraviolet (UV) rays are located just past the violet portion of the visible light spectrum; sunlight is the main source.
UV light is broken into three different types: UVA, UVB and UVC.
- UVA has longer wavelengths and passes through glass easily; experts disagree about whether or not UVA damages the eyes.
- UVB rays are the most dangerous, making sunglasses and sunscreen a must; they don't go through glass.
- UVC rays do not reach the Earth because its atmosphere blocks them.
When do UV rays affect my eyes?
The sun's rays are strongest between 10 a.m. and 2 p.m., but that's not the only time UV rays can affect your eyes.
Also, most people think that they're at risk only when they're outside on a sunny day, but UV light can go right through clouds, so it doesn't matter if the sky is overcast.
Glare and reflections can give you trouble too, so have your sunglasses ready if you'll be around snow, water or sand, or if you'll be driving (windshields are a big glare source).
Sunlamps, tanning beds, photosensitizing drugs, high altitudes and proximity to the equator also put you at greater risk.
UV damage is cumulative over a person's lifetime, which means you should begin protecting your child's eyes as soon as possible.
When do UV rays affect the eyes?
UV radiation is present year-round, so always wear proper eye protection despite the season or weather when outside during daylight hours.
Can certain medical problems increase my risk for damage from UV rays?
Yes. People with cataracts (and those who have had cataract surgery), macular degeneration or retinal dystrophies should be extra careful.
What are my options to prevent UV damage to my eyes?
You must wear sunglasses to prevent damage to your eyes. While some contact lenses provide UV protection, they don't cover your whole eye, so you still need sunglasses.
Look for sunglasses that protect you from 99 to 100 percent of both UVA and UVB light. This includes those labeled as "UV 400," which blocks all light rays with wavelengths up to 400 nanometers. (This covers all of UVA and UVB rays.)
Which lens color is the best for UV protection?
Lens color is a personal choice and doesn't affect how well sunglass lenses protect your eyes from UV light. Gray and brown are popular because they distort color perception the least.
Athletes often prefer other tints for their contrast-enhancing properties. For example, yellow lenses are popular with skiers and target shooters because they work well in low light, reduce haze and increase contrast for a sharper image.
Are impact-resistant lenses necessary?
The FDA requires all sunglass lenses to be impact-resistant. If you play sports or wear sunglasses on the job, you might want to consider ultra-impact-resistant polycarbonate lenses for even greater eye safety.
Do darker sunglass lenses provide more UV protection than lighter lens tints?
Darker sunglasses decrease the amount of visible light that passes through the lenses compared with lighter lens tints, but they don't necessarily provide greater protection from UV rays (which are invisible). For adequate protection, have your optician make sure your sunglasses block 100 percent UV, regardless of the color of the lenses.