Equivalent air change rate by upper room UVGI system

Abstract

UR-UVGI (Upper Room Ultraviolet Germicidal Irradiation) systems can be used as an additional countermeasure of ventilation systems against airborne infectious diseases in healthcare-related buildings. In this study, an UR-UVGI system was evaluated using a novel CFD simulation method in a model room used in an experimental case. The results for several cases showed inactivation rate of 98.3 ~ 96.2% for airborne vaccinia virus in the steady state condition. Equivalent air change per hour (EACH) of the UR-UVGI system was 4.5 ~ 16.5 ACH in the decay condition. Heat boxes accelerated the inactivation of airborne virus by UR-UVGI. However, the discrepancy between simulation and experiment results was observed probably because of lack of the detailed experimental conditions.