Ultraviolet radiation (UVR) exposure is the most important modifiable risk factor for skin cancer development. Although sunscreen and sun-protective clothing are essential tools to minimize UVR exposure, few studies have compared the two modalities head-to-head. This study evaluates the UV-protective capacity of four modern, sun-protective textiles and two broad-spectrum, organic sunscreens (SPF 30 and 50). Sun Protection Factor (SPF), Ultraviolet Protection Factor (UPF), Critical Wavelength (CW), and % UVA- and % UVB-blocking were measured for each fabric. UPF, CW, % UVA- and % UVB-blocking were measured for each sunscreen at 2 mg/cm² (recommended areal density) and 1 mg/cm² (simulating real-world consumer application). The four textiles provided superior UVR protection when compared to the two sunscreens tested. All fabrics blocked erythemogenic UVR better than the sunscreens, as measured by SPF, UPF, and % UVB-blocking. Each fabric was superior to the sunscreens in blocking full-spectrum UVR, as measured by CW and % UVA-blocking. Our data demonstrate the limitations of sunscreen and UV-protective clothing labeling and suggest the combination of SPF or UPF with % UVA-blocking may provide more suitable measures for broad-spectrum protection. While sunscreen remains an important photoprotective modality (especially for sites where clothing is impractical), these data suggest that clothing should be considered the cornerstone of UV protection.

The infrared optical properties of textiles are of great importance in numerous applications, including infrared therapy and body thermoregulation. Tuning the spectral response of fabrics by the engineering of composite textile materials can produce fabrics targeted for use in these applications. We present spectroscopic data for engineered polyester fabric containing varying amounts of ceramic microparticles within the fiber core and report a spectrally-dependent shift in infrared reflectance, transmittance and absorptance. A thermal transport model is subsequently implemented to study the effect of these modified properties on the spectral distribution of infrared radiation incident upon the wearer of a garment constructed of this fabric.

A popular belief for why polar bears have black skin is to increase solar heat gain from solar radiation that penetrates through a translucent fur layer made of unpigmented hollow hair. To examine the relative importance of skin color on solar heat gain, we measured thermal gradients, heat flux, and solar transmittance through a polar bear pelt under solar irradiation while thermally anchored to a temperature-controlled plate set to 33 °C. We found that for 60–70% of the dorsal region of the pelt where the fur layer is thickest, solar energy cannot reach the skin through the fur (solar transmittance ≤ 3.5 ± 0.2%) and therefore skin color does not meaningfully contribute to solar heat gain. In contrast, skin pigmentation was important in the remaining areas of the pelt that were covered with thinner fur. This information was used to select commercially available materials according to their solar optical properties to build biomimetic outdoor apparel with enhanced solar heat gain by a factor of 3 compared to standard outerwear constructions.