To give value to the hours spent in open air and safeguard eyes' health, it is fundamental to protect them against sunlight with sunglasses: those should not necessarily be trendy. It is necessary, instead, that frame fits our face, and ,above all, that solar filters are high quality.
Sunglasses protect from dangerous solar radiation and lessen the light that enters into the eye . Sunglasses with filters or high quality filter lenses are the best way to protect eyes from damages induced by sunlight .To be high quality they have to eliminate UV rays, reduce in a significant way transmission of IR rays ,reduce intensity of visible radiation and not alter the chromatic balance of visual perception.Classification of protective solar filters and, indeed of sunglasses, consider the level of protection and use. The standard EN 1836/1997 consider five classes, called protection categories ,that are estalished depending on the quantity of light that the filter allows ( transmittance) : the higher the number is , the more the filter absorbs the light radiation .
The use of sunglasses with high quality filters is of fundamental importance during holidays (the sand on the beach or the snow on ski runs) transmit high doses of UV rays and blue light towards the eye; but it is also appropriated for the city, and it is a good rule to wear them also when the sky is not so bright. If filters are of high quality, they protect against damages and safeguard the skin around the eye against premature aging, contributing in delaying wrinkles development. If filters are of low quality, they are not only useless, but also damaging because they facilitate a major pupil opening (mydriases) and, as a consequence, an increase of passage of blue and UV radiations.
In case of sun, the most risky category is those of children, in which protective action of crystalline isn't effective yet nei quali A part of their parents undervalues prolonged sunlight exposure, and do not provide their children with adequate sunglasses. The purchase of high quality glasses is indeed the starting point for a correct visual prevention; if opportunely adapted to the size of child's face, they will not bother him and they will guarantee safety and protection when exposed to the sun. Children's eyes are sensitive and delicate and so it is a lot more important to protect them with high quality sunglasses.
Through: ProfessionalOptometry
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