Comparison of performance of heat recovery ventilator and air purifier in reducing indoor PM10 concentrations in a classroom

Recently, outdoor particulate matters have become a serious problem in Korea. Pollutants exhausted from industrial plants and dust transported from adjacent regions contribute to the peaks in fine particle concentration. Indoor air quality is affected by ambient air pollution. Common methods for maintaining good IAQ from harmful outdoor particles are either through the usage of an air purifier (AP) or to install a filter in the heat recovery ventilator (HRV) system. It is important to evaluate the PM10 concentrations in a room using APs and HRVs depending on various system parameters, such as building air-tightness, indoor generation characteristics, and system filter efficiency. The purpose of this study is to compare the performance of AP with that of HRV in reducing PM10 levels in a classroom based on computer simulation. Results show that the filter efficiency of HRV should be increased to over 0.8 under the reference condition in order for the HRV to be compatible with the AP. Increasing the airflow rate of HRV is not an effective way of increasing its filter performance to outperform an AP. We found that HRV performs better as compared to AP in an indoor environment under dusty conditions with the generation rate of over seven times compared to the reference condition