Your clothing doesn’t just look great. It also absorbs or blocks harmful UV radiation and remains one of the most effective forms of protection against sun damage and skin cancer.
What’s more, sun-protective clothing is the simplest way to stay safe; unlike sunscreen, you never need to reapply!
What is the UPF & why it matters
Ultraviolet Protection Factor (UPF) indicates how much UV radiation (both UVB and UVA) a fabric allows to reach your skin. For example, a UPF 50 fabric blocks 98 percent of the sun’s rays and allows two percent (1/50th) to penetrate, thus reducing your exposure risk significantly.
What you need to know: A fabric must have a UPF of 30 to qualify for The Skin Cancer Foundation’s Seal of Recommendation. A UPF of 30 to 49 offers very good protection, while UPF 50+ rates as excellent.
How does UPF differ from SPF?
UPF measures the amount of UV radiation that can penetrate fabric and reach your skin. Sun Protection Factor, or SPF, is based on the time it takes for UV-exposed skin to redden; if you burn after 20 minutes, if used correctly, an SPF 15 sunscreen may protect your skin 15 times longer.
Another important distinction: UPF measures both UVB and UVA rays, while SPF measures only UVB.
What makes clothing sun safe?
Yes, your clothing shields you from the sun, but not all fabrics and colors provide equal protection. Luckily, you have plenty of options. When shopping for apparel that can effectively shield you from harmful rays, keep these factors in mind:
Color: Dark or bright colors keep UV rays from reaching your skin by absorbing them rather than allowing them to penetrate. That’s why these colors offer better protection than lighter shades.
Construction: Densely woven cloth, like denim, canvas, wool or synthetic fibers, are more protective than sheer, thin or loosely woven cloth. Check a fabric’s sun safety by holding it up to the light. If you can see through, UV radiation can easily penetrate the fabric and reach your skin.
Content: The composition of your fabric really matters. Unbleached cotton contains natural lignins that act as UV absorbers. Shiny polyesters and even lightweight satiny silks can be highly protective because they reflect radiation. High-tech fabrics treated with chemical UV absorbers or dyes prevent some penetration from UV rays.
Fit: Loose-fitting apparel is preferable. Tight clothing can stretch and reduce the level of protection offered, as the fibers pull away from each other and allow more UV light to pass through.
UPF: Some clothing makers provide UPF labels, which indicate exactly how much of the sun’s rays the garment can shield. Look for our Seal of Recommendation whenever you shop.
Coverage: The more skin your outfit covers, the better your protection. Whenever possible, choose long-sleeved shirts and long pants or skirts.
Activity: Regardless of UPF, if your clothing gets stretched or wet, it will lose some of its protective ability and become more transparent, exposing your skin to more UV light.
Source; Sun-Protective Clothing. www.skincancer.org