![Sample our Engineering & Technology journals, sign in here to start your access, latest two full volumes FREE to you for 14 days]({"type":"image" , "src" : "/sda/5933/TOC-Subject-Sample-2021-Engineering-Tech.jpg"})
Abstract
Room air disinfection by upper air UV was studied in relation to temperature gradients. When upper air temperature minus lower air temperature ranged between +7 and -2 F, the rate of disappearance of test organisms from the lower air, with two UV fixtures operating, averaged 33 equivalent air changes per hour (AC/hr), and when the temperature difference ranged between -3 and -5 F, the rate of disappearance averaged 83 AC/hr. Estimates indicated that the rate of air exchange between the upper and lower parts of the room averaged about 25 AC/hr when air entering at the ceiling was warmer than lower room air and exceeded 125 AO/hr when air entering at the ceiling was 3 F or more cooler than the air in the lower part of the room.