If buying sunglasses is to remain a pleasure, some advice is necessary. Lenses, protection, frames, colour…
When choosing your sunglasses, which are available on the second-hand market, you should check that they carry the CE marking and the protection category 0 to 4. There are several types of filter lenses: mineral (scratch-resistant but sensitive to shocks) and organic (light and shock-resistant). Some can be treated with anti-reflective, photochromic or other coatings, such as anti-reflective or photochromic.
Dark glasses are not necessarily the most effective…
Even though fashion is often favoured, certain precautions should be taken before giving in to the purchase. Be careful, to be sure of the quality of your sunglasses, choosing a very dark shade is not enough. The quality of filtration of harmful rays is the first thing to check. For example, certain transparent corrective lenses may be sufficiently protective.
Choosing the right protection factor
The protection category varies from 0 to 4, the higher the index, the more it reduces the light intensity.
Sunglasses category 0 are aesthetic comfort glasses, they offer very little protection against UV rays;
The filtering sunglasses of category 1 is recommended for situations of reduced sunshine ;
Category 2 sunglasses are suitable for medium sunlight;
Category 3 sunglasses are ideal for the classic situations of strong sunlight: sea, mountains, winter sports… ;
Category 4 sunglasses are the most powerful filters: they are adapted to extreme light conditions where the sun reflects in the snow (mountaineering, glaciers, etc.).