“…52 In general, hydration results in a reduction in the UPF because of the presence of water in the interstices of the fabrics, which leads to an increase in UV transmission. 53 On the other hand, in fabrics made of viscose or silk, or in fabrics that have been treated with broad-spectrum UV absorbers, the UPF frequently increases when the textile becomes wet. 53 In fact, Gambichler et al 54 have concluded that one can not predict the UPF value of any given fabric when wet, because the value varies depending on the type of the fibers, and the change in scattering and absorption properties of the fabrics.…”