Effect of Flow Rate and Filter Efficiency on Indoor PM2.5 in Ventilation and Filtration Control

Abstract

Ventilation and filtration control play a critical role in determining indoor PM2.5 (particles less than 2.5 μm in aerodynamic diameter) concentrations of outdoor or indoor origin in residential environments. The objective of this study was to investigate the combined effects of flow rates and filter efficiency on indoor PM2.5 concentrations of residential buildings in Seoul, Korea. Using a particle model based on a mass–balance equation, parametric analysis was performed to examine indoor PM2.5 concentrations according to flow rates and filter efficiency under a wide range of outdoor concentrations and indoor generations. Results showed that ventilation control equipped with a medium–efficiency filter was as effective as that with a high-efficiency filter under normal outdoor concentration and high indoor generation rate conditions. It is not recommended to apply a low-efficiency filter because indoor concentration increases rapidly as outdoor PM2.5 increases when ventilation flow rate is high. For filtration control, it is important to increase both flow rate and filter efficiency in order to improve indoor PM2.5 concentration.

The effect of COVID-19 restrictions on particulate matter on different modes of transport in China

“…Indoor particle removal is due to ventilation, deposition onto indoor surfaces, and indoor air filtration system, which is fitted to a natural decay curve over a portion of the decay period ( Kim and Yeo, 2020 ). Here we used decay rates (DRs) to assess particle's removal efficiency in the air on transport.…”

“…Here we used decay rates (DRs) to assess particle's removal efficiency in the air on transport. The DRs (h −1 ) were estimated for car, inter-city bus, high-speed train, and airplane by fitting the natural decay curves of PM ( Kim and Yeo, 2020 ). We used both PM 10 and PM 2.5 for each decay curve, selected curves that had changes as big as possible and that followed (at least roughly) the expected declining exponential trend, as shown in eq.…”

Performance Evaluation of Particulate Matter and Indoor Microclimate Monitors in University Classrooms under COVID-19 Restrictions

“…Consequently, maintaining adequate air exchange rates do not replace or reduce the need to control indoor sources of emission of harmful chemicals [ 15 ]. Ventilation and filtration control play certainly a critical role in the variability of indoor PM2.5 concentrations of indoor or outdoor origin in different residential environments including educational facilities [ 59 ]. In the current work, the experiments relied on ‘no filtration’ conditions because the building in which the room is located still does not have a ventilation/filtration unit.…”

Ventilation and Filtration Control Strategy Considering PM2.5, IAQ, and System Energy

“…To obtain the values of the coefficients (P, k, η v , and η f ) required for the indoor PM model, experiments were conducted before the verification experiments, and the results are shown in Tables 1 and 2. A more detailed description of the measurement setup was reported previously [27]. Briefly, experiments were conducted successively for 20 days from 4 July 2017 to 23 July 2017 in a newly constructed apartment.…”