Evaluation on Air Purifier’s Performance in Reducing the Concentration of Fine Particulate Matter for Occupants according to its Operation Methods

Abstract

Fine particulate matter entering the body through breathing cause serious damage to humans. In South Korea, filter-type air purifiers are used to eliminate indoor fine particulate matter, and there has been a broad range of studies on the spread of fine particulate matter and air purifiers. However, earlier studies have not evaluated an operating method of air purifiers considering the inflow of fine particulate matter into the body or reduction performance of the concentration of fine particulate matter. There is a limit to controlling the concentration of fine particulate matter of the overall space where an air purifier is fixed in one spot as the source of indoor fine particulate matter is varied. Accordingly, this study analyzed changes in the concentration of indoor fine particulate matter through an experiment according to the discharging method and location of a fixed air purifier considering the inflow route of fine particulate matter into the body and their harmfulness. The study evaluated the purifiers’ performance in reducing the concentration of fine particulate matter in the occupants’ breathing zone according to the operation method in which a movable air purifier responds to the movement of occupants. The results showed the concentration of fine particulate matter around the breathing zone of the occupants had decreased by about 51 μg/m3 compared to the surrounding concentration in terms of the operating method in which an air purifier tracks occupants in real-time, and a decrease of about 68 μg/m3 in terms of the operating method in which an air purifier controls the zone. On the other hand, a real-time occupant tracking method may face a threshold due to the moving path of an air purifier and changes in the number of occupants. A zone controlling method is deemed suitable as an operating method of a movable air purifier to reduce the concentration of fine particulate matter in the breathing zone of occupants.

Distribution Characteristics of Indoor PM2.5 Concentration Based on the Water Type and Humidification Method

“…Both models use the light-scattering method to measure the indoor PM concentration, but the costs differ by more than 10 times. While AM510 is already used by numerous studies owing to its verified accuracy and reliability, TES-5322 has not been frequently used despite its economic efficiency [ 25 , 26 , 27 , 28 ]. The measurement accuracy of TES-5322 is below ±5 μg/m 3 when the PM 2.5 concentration is less than 50 μg/m 3 and below ± 10% when the PM 2.5 concentration is greater than 50 μg/m 3 .…”

“…With regard to the equilibrium equations of the PM 2.5 concentration in the steady state in a small chamber, this study used Equation (1), which was changed from the concentration equation for indoor pollutants in a steady state, and Equation (2), which is used to calculate the final state value of the mixture at by-pass by using the mixing ratio of each content [ 23 , 24 , 25 ]. In other words, the amount of the generated PM and the concentration emitted from the humidifier can be calculated using Equations (1) and (2) if the exhaust airflow rate of the chamber, PM 2.5 concentration flowing into the chamber, and concentration of the calibration points are known.…”

Indoor air quality improvement in COVID-19 pandemic: Review

“…Air purifiers can capture a substantial amount of airborne dust particles and airborne allergens ( Sublett, 2011 ). For instance, experimental studies conducted by ( Park, Park, & Seo, 2020 ; Yoda et al, 2020 ) under everyday life conditions stated that the air purifiers were effective in reducing indoor PM concentration depending on the user location and the subject characteristics. The study done by ( Chen et al, 2010 ; Zhang et al, 2019 ) signified that the usage of air purifiers limited the exposure of aerosols and droplets on healthcare workers in dental clinics significantly.…”

Integrated Human Exposure to Air Pollution

“…For instance, in some countries, such as South Korea, filter-type air purifiers are used to eliminate fine particulate matter from indoor environments. A study assessed the performance of this type of solution to reduce particulate matter levels in a person’s breathing zone, according to two approaches: a movable air purifier responding to the movement of persons in the room or a fixed air purifier [ 11 ]. The results showed a decrease of 51 μg/m 3 and 68 μg/m 3 from the implementation of these two strategies, respectively.…”