摘要：In this study, a day-care center located in Seoul was monitored for one year to quantify the effects of ventilation methods, natural and mechanical, on the indoor particle levels. It is found from the field monitoring that air tightness and mechanical ventilation system with MERV 12 can be helpful to maintain indoor particles at low levels during the class hours of the day-care center. The mechanical ventilation, however, is not sufficient for lowering PM2.5 when the outdoor PM2.5 is at high levels.
