Asked by: Anonymous
Skin is damaged by ultraviolet radiation in sunlight, especially so-called UV-B, the relatively short-wavelength variety known to trigger skin cancer. The good news is that UV-B can’t penetrate through glass. The bad news is that the far more common, longer-wavelength UV-A, which also causes wrinkles and skin ageing – it can pass through glass. It’s also now thought to increase skin cancer risk as well, making sitting near windows a potential threat to health as well as appearances.
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