1. Can UV-C effectively inactive the SARS-CoV-2 virus, responsible for COVID-19?
    Yes, if the virus is directly illuminated by UV-C at the effective dosage.
  2. Does the UV in sunlight have germicidal properties?
    Yes, in late spring and early summer when the sun is high in the sky and the UV index is high. At a UV index of 10, the durationto achieve at least a 3-log kill of bacteria (99.9%) is estimated as less than one hour. 
  3. Can whole-room UV-C effectively inactivate the SARS-CoV-2 virus responsible for COVID-19?
    Yes, upper room UV is the safest and most effective application for UV-C in occupied spaces. In special locations whole-room UV-C from suspended fixtures directing UV-C downward could be applied, provided that strict precautions can be followed, wearing protective clothing and eye protection.
  4. Is UV inside air ducts or air handlers sufficient for room-air disinfection?
    UV inside ducts ensures that recirculated air does not have viable pathogens, it does relatively little to prevent person-to-person transmission in a room where a infectious person shares the same air as other people.
  5. Does UV degrade paints, wall material, or hurt plants?
    UV rays in general will degrade paint and yellow plastics. Shorter-wavelength UV photons have higher energy potential than longer-wavelength UV photons, and may have an accelerated aging effect on materials and paints, and may damage plants.

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