CHARACTERIZATION AND PERFORMANCE OF A PUSH-THROUGH FAN-FILTER UNIT SYSTEM IN MITIGATING HAZE EXPOSURES IN NATURALLY VENTILATED HOSTELS

Abstract

A push-through fan-filter unit system is used to address the haze issues in naturally ventilated hostel rooms. A series of measurements were conducted as three different experimental studies, which will eventually conclude on the particulate removal efficiency, thermal comfort and acoustic performance of the fan-filter unit system. The first study is focused on filtration efficiency testing of MERV 13 filter at 4 different fanfilter distance (50mm, 100mm, 150mm, and 200mm), with a fixed fan speed to evaluate the fan-filter unit system performance under unimpeded condition. It was found that 50mm fan-filter distance has the best overall performance. After which, 50mm fan-filter distance was adopted for the subsequent two field studies in a hostel room and research room to test its application and feasibility of the fan-filter unit system. The findings from these studies showed that the I/O ratios for the particulate matter were in the range of 0.06 to 0.19, significantly lower than the control room study conducted. This indicates that the push-through fan-filter unit system is effective in removing particulate matter indoors. Moreover, thermal comfort analysis also found that temperature and relative humidity were in the acceptable range according to the Adaptive Comfort Standard by ASHRAE 62.1. Furthermore, the fan-filter unit system generates acceptable sound levels to its occupants, which is an essential factor to note in a hostel room application. Hence, the fan-filter unit system is suitable for prolonged use without disrupting the occupant’s activity. Nevertheless, the results also suggest other factors that affect the performance of the fanfilter unit system. The factors are ACH, air velocity through the fan-filter unit system, indoor sources of pollutants, and deposition rates of particles. They are further discussed on their implications on the fan-filter unit system’s performance in this study.