It is common knowledge that the sun gives off harmful UV (ultraviolet) rays. There are constant campaigns to raise awareness of the potential harm of the sun’s rays on TV, radio and in print. What people are less aware of are the UV-rays that are emitted from artificial machines, for example sun beds. These can be just as harmful, if not more so. Sun screens are developed to protect our skin, however, what is done to protect our eyes?
UV rays come in three types, UV-C, UV-A and UV-B. UV-C is soaked up by the ozone layer, as it never reaches the surface of the earth it is of no threat to us. The second two do get through the earth’s atmosphere and can cause long lasting damage to your eyes and vision.
UV-rays are ultimately form of radiation. Over exposure to your skin causes it to burn. Over-exposure to your eyes causes something called photokeratitis. Main symptoms include redness around the eye, dryness, high sensitivity to light and excessive over-watering. Thankfully, this condition isn’t normally permanent. However, long term exposure to UV-rays can cause cataracts and damage the retina.
There are number of easy ways that you can avoid over-exposure of UV-rays to your eyes. Wearing sunglasses (with approved UV filters) and wide-brimmed hats is a simple and easy way to protect yourself. There is such a wide selection of sunglasses on the market that there will always be an option for you. Most plastics give some sort of protection from UV-rays, but, when selecting sunglasses there are a few things that you need to consider. Sunglasses should block out 99-100% of UV-A and UV-B rays, they should also screen up to 90% of visible light and the lenses should be gray so not to hamper your normally colour recognition. You should look out for stickers with the CE symbol and “100% UV 400”. This is widely known these days, and nearly all reputable sunglasses manufacturers adhere to these standards, from fashion brands like Tom Ford to sporting ones like Oakley sunglasses.
Mountaineers need high-performance sunglasses as they are exposed to more UV-rays that normal. Many sunglasses designed for mountaineers wrap around their heads to ensure that all light is filtered through the glasses and doesn’t go directly into the eye.
Fashion sun-glasses are not restricted by such functionality; this allows designs to be more creative. Over the years, different designs have been more fashionable than others. For examples, the classic Ray Bans, originally designed for the US Army, have always been on-trend. More recently the wide-eyed 70s style has proved more popular with fashionistas. However, in every case, UV-protection is a key requirement for the glasses. Only when you are buying fake designer glasses should you be wary, as these glasses are not constrained by normal EU regulations.