By Tom Burden
Clothes can be an effective defense against the sun’s harmful ultraviolet (UV) rays, protecting us from sunburn, rapid skin aging and skin cancer. Many people do not require sun protection for skin that is covered by garments, especially if you have average to darker skin color. Others, especially children, those who are fair-skinned, or who spend lots of time on the water, at high altitudes or in equatorial latitudes require extra protection. However, not all clothing is sun-protective. What should you look for? A UPF rating of 15 (good UV protection) to 50+ (excellent UV protection).
UPF stands for Ultraviolet Protection Factor and indicates how much of the sun’s UV radiation penetrates a fabric and reaches your skin. Fabric with a rating of 50 will allow only 1/50th of the sun’s UV rays to pass through. This reduces your skin’s UV radiation exposure significantly because only two percent of the UV rays will get through. Factors that effect the UPF rating of a garment include its color (lighter colors generally have lower UPF ratings than darker colors), the size of the yarns the product is constructed from and their opacity and fiber content, the tightness of the knit or weave, and optical brighteners added in the dyeing process.
Consider that plain, white cotton T-shirts have an average UPF of 7, and if they get wet, the UPF drops to only 3—virtually no protection! High-tech clothing like the Columbia sportswear found in our catalog takes advantage of special fabrics that are woven to block UV rays.
|UPF Rating||Protection Category||Percent of UV Radiation Blocked|
|UPF 15 - 24||Good||93.3 - 95.9|
|UPF 25 - 39||Very Good||96.0 - 97.4|
|UPF 40 - 50+||Excellent||97.5 - 99+|