What Does UV 400 Mean?.
UV400: What It Means and Why It's Important for Your Eyes
Introduction:
UV400 is a rating that indicates that sunglasses block 99-100% of all ultraviolet (UV) rays up to 400 nanometers. This includes both UVA and UVB rays, which are the two most harmful types of UV radiation.
UV rays can damage your eyes in a number of ways, including:
- Cataracts: Cataracts are a clouding of the eye's lens that can lead to vision loss. UV rays are a major risk factor for cataracts.
- Macular degeneration: Macular degeneration is a condition that damages the macula, the central part of the retina. This can lead to blurred vision and central vision loss. Macular degeneration is the leading cause of blindness in adults over the age of 50.
- Pterygium: Pterygium is a growth of tissue that can form on the conjunctiva, the clear membrane that covers the white part of the eye. It can be unsightly and can interfere with vision if it grows large enough. Pterygium is more common in people who spend a lot of time outdoors.
- Photokeratitis: Photokeratitis is a painful inflammation of the cornea, the clear front part of the eye. It can be caused by exposure to UV rays, especially from sunlight reflected off of sand or water.
Why is UV400 protection important?
UV400 protection is important because it blocks both UVA and UVB rays. UVA rays are thought to be responsible for most of the long-term damage to the eyes, such as cataracts and macular degeneration. UVB rays can cause more immediate problems, such as photokeratitis and sunburn of the eyelids.
How do you know if your sunglasses have UV400 protection?
Look for a label on the sunglasses that says "UV400" or "100% UV protection." If you can't find a label, ask the retailer if the sunglasses have UV400 protection.
What other factors should you consider when choosing sunglasses?
In addition to UV400 protection, there are a few other factors to consider when choosing sunglasses, including:
- Lens tint: The tint of the lenses will affect how much visible light is blocked. Darker lenses block more light, but they can also make it difficult to see in low-light conditions. Lighter lenses block less light, but they may not provide enough protection in bright sunlight.
- Lens material: Sunglasses are typically made from either plastic or glass. Plastic lenses are lighter and less likely to break, but they can also scratch more easily. Glass lenses are more scratch-resistant, but they are also heavier and more likely to break.
- Fit: Sunglasses should fit snugly but comfortably. The lenses should cover your entire eyes and the frames should not block your peripheral vision.
How to protect your eyes from UV rays:
In addition to wearing UV400 sunglasses, there are a few other things you can do to protect your eyes from UV rays, such as:
- Wear a hat: A hat can help to shade your eyes from the sun.
- Avoid the sun at midday: The sun's rays are strongest between the hours of 10 a.m. and 4 p.m. If possible, try to avoid being outdoors during these times.
- Use sunscreen: Apply sunscreen to your face and eyelids, even on cloudy days.
Conclusion:
UV400 protection is essential for protecting your eyes from the harmful effects of UV radiation. When choosing sunglasses, look for a pair that has UV400 protection and that fits you comfortably. You may also want to consider other factors, such as lens tint and lens material.