The World Health Organization estimates 16 million people go blind every year from cataracts. Up to 20% of these cases can be linked to over exposure of the eyes to UV radiation.
While few statistics are kept, many law enforcement, safety, and medical personnel will tell you that sun glare is a contributing factor in a number of automobile and off-road vehicle accidents every year.
Temporary but painful loss of site, and occurs especially in snowy or wet conditions, where the UV rays are reflected – even on cloudy days! Many snowmobilers, skiers, and others suffer from this every year in North America.
Sunlight is very bright, and looking directly at the Sun is painful to the eyes. Looking directly at the Sun when it is high in the sky causes temporary bleaching of the photosensitive pigments in the retina, which makes phosphene visual artifacts and may cause temporary partial blindness. Direct viewing of the Sun with the naked eye delivers about 4 milliwatts of sunlight to the retina that is in the solar image, heating it up and potentially (though not normally) damaging it. Brief viewing of the direct Sun with the naked eye is unpleasant but generally safe. Long-term exposure of the eyes to direct sunlight contributes to the normal UV-induced yellowing of the lens and cornea over periods of decades, and could play a part in the formation of cataracts.
Protect Your Eyes from Sun Damage
UV rays are invisible, high-energy rays of light that, if absorbed by your eyes, can cause or enhance several eye ailments. This happens because the UV light can cause a reaction in our eye tissue. And once it occurs, it cannot be reversed.
The UV rays can play a large role in the following eye diseases:
Cataract – Clouding of the eye; causes blurring or dimming of vision – UV rays are the largest culprit in the formation of cataracts
Pteryguim – Tissue growth on the whites of eyes; can block vision
Skin cancer – Eyelids and facial skin can develop melanoma
Age-related macular degeneration – Deterioration of the eye’s macula (sensitive center of the retina
Taking care of your eyes should be a top concern for all no matter the time of the year, but especially during the hot summer months of June, July and August.
Sunglasses provide one of the best sources of UV protection. In order to properly protect your eyes, choose motorcycle sunglasses that over at least 95 percent UV protection. Also, choose a lens tint that blocks 80 percent of transmissible light, but no more than 90-92 percent of light because lens tint does not protect you from UV rays, and can affect your ability to see correctly. Large lenses that fit close to the eyes are best. Those that block visible blue light are even safer.
Snow can be Blinding
(NC)-We’ve all heard the expression “a blinding snowstorm”. Though that refers to whiteout conditions where visibility is reduced, make no mistake, the snow can be blinding too. Bright sun reflecting on a blanket of fresh white snow can reflect damaging rays into unprotected eyes. The casualty may not be aware of the damage at the time – not feeling the effects for up to several hours.
Watch for these symptoms of snow blindness:
Eyes become sensitive to light
Pain in eyes or forehead
Gritty feeling in the eyes.
Snow Blindness – From Wikipedia, the free encyclopedia
Snow blindness is a painful condition, typically a keratitis, caused by exposure of unprotected eyes to sunlight reflected from snow. This is especially a problem at high altitude and polar regions. The problem is also related to the condition arc eye sometimes experienced by welders. Snow blindness does not usually cause permanent vision loss. Resting the eyes in a dark room for several days will cause the pain and symptoms to disappear.
The Inuit carved goggles from caribou antler to help prevent snow blindness. The goggles were curved to fit the users face and had a large groove cut in the back to allow for the nose. A long thin slit was cut through the goggles to allow in a small amount of light. The goggles were held to the head by a cord made of caribou sinew.
When trekking or mountaineering, sunglasses that offer the following are frequently recommended:
99-100% UV absorption
Polycarbonate or CR-39 lens (lighter, more comfortable than glass)
5-10% visible light transmittance
Large lenses that fit close to the face
Wraparound or side-shielded to prevent incidental light exposure