Topic of sun protection is endless, but one thing is rarely mentioned – the sun protection function of clothing.
Blocking sunlight and providing sun protection seems obvious for clothing, but how to measure its effectiveness is not well-known. Sun protection factors such as SPF or PA are commonly used to measure sunscreen effectiveness, while the sun protection factor for clothing is measured using UPF (UV Protection Factor). UPF measures the change in intensity of UV radiation before and after passing through a material in a laboratory. Few people are aware that clothing has UPF, and manufacturers rarely provide sun protection data for their products. How effective is clothing at sun protection? Many experts believe that over 90% of summer clothing has a UPF higher than 10, equivalent to SPF 30 or above, and over 80% of summer clothing has a UPF higher than 15, equivalent to almost complete UV blockage.
Different materials have different sun protection capabilities, and interestingly, studies have found that after washing, clothing has a higher UPF than new clothing. The reason is simple – the fibers of the clothing shrink after washing, reducing the gaps between the fibers. The size of the gaps determines the penetration of UV radiation, which in turn determines the UPF.
Can the sun protection of fibers be increased? Some fiber materials and even laundry detergents claim to contain sun protection ingredients. One such ingredient is Tinosorb, a chemical sun protection that, when fused with clothing fibers, absorbs UV radiation and enhances the sun protection effect of clothing. Tinosorb has the advantage of not damaging clothing or causing discoloration, and is a widely used sun protection ingredient.
Sun protection is not only important for the face, but also for exposed parts of the body to slow down skin aging. Long-sleeved clothing provides adequate protection for the skin in intense sunlight. Remember to protect yourself well!