Effects of visible greenness, quantity and distance of indoor plants on human perceptions and physical parameters
Ke-Tsung Han
Abstract
The main purpose of this study was to examine the influence of visible greenness rate, green coverage ratio and distance from plants on human perceptions and parameters of the physical environment. A secondary purpose was to explore the correlation between parameters of physical environment and human perceptions when indoor plants were present. A randomized controlled trial was conducted. Experimental treatments were administered by placing either three or eight pots of Radermachera hainanensis Merr. in a room. Sixty students of a technology university in central Taiwan were recruited as participants, and their perceptions were collected using a questionnaire. Physical parameter data were collected using two air quality detectors. The results indicated the following: when the visible greenness rate was identical, different green coverage ratios and plant–participant distances did not exert different effects on participants' perceptions. Different green coverage ratios and distances from plants exerted differing effects on physical parameters. However, the distance from indoor plants had stronger and more consistent effects on physical parameters than the green coverage ratio. The environmental comfort of the participants increased with the CO 2 level, and the lower the level of total volatile organic compound, the higher is the level of surprise.