Sunglasses are not just a fashion statement; they serve to protect one’s eyes against UV radiation. Hence, the question: how can you make sure your sunglasses actually block the harmful rays? Here’s a manual for checking and confirming that the glasses you own do provide the promised UV protection.
Official Label
The most basic way to check if the sunglasses have UV protection is to look for some kind of label or sticker on them. Normally, good sunglasses will have some information printed on them, like “100% UV Protection” or “UV400.” According to a notation, UV400 denotes lenses capable of blocking all light rays with wavelengths up to 400 nanometers, which means they block both UVA and UVB rays.
UV Testing Machine
A good number of optical shops and sunglass dealers have machines in which they can test the levels of UV protection their lenses offer. To test your sunglasses:
Simply place the lenses under this machine’s testing sensor.
Check the reading; the higher the percentage, approximately up to 100%, the better the protection against UV rays.
Polarization as a Plus
While polarization does not directly relate to UV protection, it does add comfort in that it cuts the glare from any reflective surface, be it water or the road. So, if your shades happen to be polarized and labeled with UV400, you just achieved the best clarity coupled with protection.
UV Testing at Home
In case you do not have a UV tester at home, you can still perform a small test using a simple flashlight:
Shine the UV flashlight through the sunglasses onto a UV-sensitive material, e.g., a UV-detection card.
If the material responds with less or no change, then it implies that the lenses are effectively blocking UV light.
Conclusion
Protecting your eyes from UV damage improves vision in the long-term. You can assure yourself that your sunglasses offer the right protection by checking for clear labels, getting them tested on UV machines, or carrying out a simple home test. Do not compromise on quality— because your eyes are worth it!
