The effect of indoor plants on human comfort

There is growing evidence to support the notion that plants can play an important role in providing a higher quality living environment. This study conducted a series of experiments to investigate the effects of characteristics, such as colour, odour and size of plants on human comfort, which was evaluated by a satisfaction survey and physiological measurements. Different kinds of plants with different levels of colour (green, tint and multicolour), odour (no odour, slight scent and strong scent) and size (small, medium and large) were chosen for the experiment design. A survey of participants' satisfaction degree as well as measurements from electroencephalogram (EEG), electrocardiogram (ECG), oxyhaemoglobin saturation, fingertip blood flow, skin resistance and respiration rate were utilized to illustrate the response of participants to the environments either with different plants or without plants. The results demonstrated that an interior office with plants was preferred over an office without plants. The environments with green, slightly scented and small plants were reported as the most favourite conditions. The EEG and oxyhaemoglobin saturation showed significant changes when plant conditions varied. These outcomes provided design strategies for incorporating the plants into the interior office spaces and also provided the physiological variables to evaluate human comfort in the outside environment.