1. Check the labeling
Look closely at the frames and lenses. Sunglasses with true UV protection are typically labeled "UV 400," meaning they block 100% of both UVA and UVB rays. If the labeling is unclear or missing, you should examine the product more closely. Many manufacturers also list relevant certifications to document that the sunglasses meet international standards.
2. Use a UV test card
A UV test card is a simple tool that can show whether sunglasses are effectively filtering UV light. Hold the sunglasses in front of a light source and compare the color change on the test card. A clear difference in color indicates that the lenses are blocking the harmful rays.
3. Get a professional assessment
For a thorough evaluation, you can have your sunglasses tested by an optician or a testing laboratory. Special equipment measures how the lenses process UV rays, giving you an accurate answer to their protection.
Frequently asked questions:
• What does "UV 400" mean?
"UV 400" indicates that the sunglasses block 100% of UVA and UVB rays.
• How does a UV test card work?
The card changes color if the lenses do not filter UV light properly.
• Where can I have my sunglasses professionally tested?
Contact your local optician or a specialized testing laboratory for a UV measurement.
• What do certifications do regarding sunglasses?
Certifications document that the sunglasses comply with applicable international standards for UV protection.