Selection of ornamental plants for PM2.5 reduction inside the buildings by using a vertical green wall system

Abstract

Thailand has experienced air pollution problems from particulate matter of 2.5 microns (PM2.5) or smaller. It directly affects health of population in the country. However, PM2.5 dust is not only in the open area, but also inside the building. Indoor corridors were also found to have excesses of PM2.5 more than standard. It affects the health of building occupants. This research aims to select an appropriate ornamental plants for using indoor to prevent the PM2.5 problem. 10 types of ornamental plants were studied in an experimental box. It has a vertical wall style and an air circulation fan at the bottom. The experiment was divided into 2 groups which are with a circulation fan on and off. The study results showed that Episcia cupreata (Hook.) can reduce PM2.5 dust effectively. It can reduce 6.17 * 10^-3 µg/m³/cm²/hr when the circulation fan is turned on and 6.32 * 10^-3 µg/m³/cm²/hr when the fan is off. It can reduce PM2.5 through the plant's leaf surface within the standard in 30 minutes and 150 minutes for air circulation fan on and off, respectively. Therefore, this study recommends the use Episcia cupreata (Hook.) to install in a vertical green wall system with the use of circulation fan to reduce PM2.5 inside the building.