UVblocking

UVblocking refers to the reduction or prevention of ultraviolet radiation reaching the skin, eyes, or materials. It encompasses products, coatings, and materials designed to absorb, reflect, or scatter UV light in the UV-A (315–400 nm) and UV-B (280–315 nm) ranges. UV-blocking properties can be intrinsic to a material or achieved through treatments applied to surfaces or fabrics.

Common approaches include sunscreen formulations that use chemical filters or mineral UV blockers (such as zinc oxide or titanium dioxide) to absorb or reflect UV radiation. Clothing and textiles with ultraviolet protection factors (UPF) are manufactured to limit UV transmission, often through fiber selection, weave, and dyes. Eyewear such as sunglasses may offer UV400 or 100% UV protection to block UVA and UVB rays. Other everyday barriers include hats, umbrellas, and UV-blocking films or coatings on windows and automotive glass.

Standards and testing methods assess how much UV is transmitted. UPF ratings indicate the fraction of UV radiation transmitted by fabric, while eyewear standards specify the percentage of UV blocked. Window films and coatings are evaluated for UV reduction and durability under exposure. It is common for products to advertise broad-spectrum protection and, in some cases, a certification label.

Limitations include degradation of materials over time, incomplete coverage, and the need for proper application and reapplication where applicable (as with sunscreen). UV blocking is part of a broader strategy for reducing UV exposure, which also includes shade, timing of outdoor activities, and protective lifestyle choices.