3D Modelling for Solar Erythemal UV Protection Provided by Human Hair

The study utilized a 3D numeric simulation tool, SimUVEx, to measure the UV protection provided by human hair at different head orientations and Solar Zenith Angles (SZA). The findings indicated that hair orientation and SZA significantly affect the protective factor, with the protection increasing as SZA rises. Hair arranged in parallel alignment offered 10%-30% more protection than hair in random arrangements. Despite this, there was still considerable UV exposure to the scalp, even with average hair density. The research highlights the importance of hair as a natural sunscreen and suggests that protection messages should include the scalp, especially for individuals with alopecia.