How to Block Blue or UV Light
- 1). Wear proper sunglasses. Sunglasses can block 100 percent of UV rays if you buy the proper type (the glasses will be labeled as UV protectant). Wraparound-style glasses also tend to block the most UV light because there is so little room for sunlight to slip around the peripherals. This is an important consideration since UV light can damage your eyes.
- 2). Wear sunscreen, and the higher the SPF protection the better. SPF30 should be the minimum count, since sunscreen goes up to SPF 70 and 100. To be safe you should always wear sunscreen whenever you intend on going outside and the sun is out, summer or winter. UV light may actually be worse in the winter because the light is reflected off the snow.
- 3). Pay careful attention to where you are. UV and blue light are more likely to reach you if you're in a wide open place surrounded by reflective surfaces, such as the sand on a beach or the snow on a ski slope. If you're in the shade, or if you're in an urban area where the light is blocked and diffused by the architecture, then you should be safer outside for longer periods of time.
- 4). If you are concerned about blue light, you can wear blue blockers. These are glasses with a yellow tint that block blue light rays from getting to your eyes. They also cut glare and help bring the world into a sharp focus.
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