The Development of Germicidal Air Purifier by Employing Ultraviolet System in Controlling Airborne Bacteria oleh Nur Atik, Siska Widya Dewi Kusumah, Fitria Mahrunnisa, Winni Maharani, Windi Nurdiawan, Putu Indra Cyntia Dewi, Erda Avriyanti, Dede Suhendi