UV-B (280–320 nm) transmission through both plastic and glass windshields was reported to be less than 1%. However, UV-A (320–380 nm) transmission ranged from 0.41% to 53.5%, with plastic attenuating more UV radiation than glass. 3. Intrigued by our findings and the clinical observation of pilots developing melanomas on sun-exposed skin, we Cons of Lexan: Easier to scratch. More expensive in comparison to acrylic. Poorer clarity, cannot be polished to restore clarity. Can be yellowed over time by UV rays. Low level of resistance to abrasive cleaners and surfaces. Can be dented easily. Manufacturers rate the UV resistance of fabrics according to their Ultraviolet Protection Factor (UPF). 50 is a high UPF rating and indicates that a fabric blocks 98 per cent of the sun’s rays. Anything above 50 is considered very good by most international bodies. The regulations themselves state the the material must be tolerant to UV exposure itself. Polycarbonate 4 absorbs most of the UV spectrum. Acrylic on the other hand absorbs UVB, and UVC, the most harmful type of UV radiation 5. It, unfortunately, allows some component of the UVA portion of the through (less than 50% 6). On top of this, most Laminated glass can block more than 99% of UV rays because plastic interlayers between single panes of glass absorb UV radiation. Take a look at how solar control glass and laminated glass – either individually or combined – help to maintain a comfortable home, with views and natural light and reduce the risk of overheating and faded furniture. Nylon 6, for example, is more resistant than nylon 6/6. The color of nylon parts will tend to fade over time when exposed to UV. Nylon degrades via the same mechanism as polypropylene — the radiation creates free radicals that further break down intermolecular bonds. Nylon is sensitive to UV radiation in the wavelength range of 290-315 nm. LEXAN™ Polycarbonate Films with UV Blocking Protection. LEXAN™ weatherable films utilize a coating technology that resists yellowing and hazing by protecting against the sun's harmful UV rays. Along with good UV resistance, these films also have chemical and abrasion resistance comparable with the LEXAN™ hardcoat series of films. TheDutchy. • 9 yr. ago. Wiki on Ultraviolet reads: "Ordinary window glass passes about 90% of the light above 350 nm, but blocks over 90% of the light below 300 nm." UVAI ranges from 340 to 400nm, visible light ranges from 390 to 700nm. So now I'm going to make an assumption and if I'm wrong please correct me. Approximately 4% of the sun’s radiation output is as UV, but since the ozone layer absorbs most UV-B (280-315 nm) and all UV-C (100-280 nm) radiation, about 95% of the UV we receive is UV-A (315-400 nm). To increase material longevity, most glazing plastics contain chemicals that absorb UV radiation, which is then dissipated as low-level heat. As a solution dyed acrylic fabric, it keep its color for many years. A solution dyed acrylic fabric means that each string is colored all the way through, and not only in surface like other kinds of fabrics. Choosing this fabric for your furniture or hot tub cover will preserve them from fading over time due to temperature, UV rays and rain. P7B9q.