A poster on the outside of the Seattle Space Needle, reading: "SAFER INDOOR AIR Layers of UV-C, far UV-C and air filtration technoloogy UV-C is a shortwave ray of light that is proven to effectively damage the DNA and RNA of bacteria and viruses to render them inactive. We invested in technologies that use two types of UV-C and safe, far-UV-C light. Together with the filtration systems throughout the building, this state-of-the-art equipment continuously cleans the air." The poster also has a diagram depicting how the UV technologies work.
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