The aim of the project was to study the air pollutants in airtight office building, and the ability of several plant species to reduce air pollutants. Carbon dioxide (CO2), formaldehyde, particulate matter (PM) concentrations were monitored in window type air conditioned and central air conditioning offices, and at different locations (cubicle area and printing room). Each office/location were monitored for seasonal effect (summer and winter). Results showed that indoor CO2 concentration was higher in the central air conditioning office than in the window type air conditioned office during summer. Indoor formaldehyde concentration was higher in the central air conditioning office than in the window type air conditioned office, higher during summer than winter, higher in the printing room than cubicle area, and higher when without plant decoration than those with plant decorated. Over all PM concentration was higher during winter than summer, with central air conditioning office higher than the window type air conditioned office. Twenty-three indoor plant species, including six Taiwan-native species, were placed in the offices. Results showed that many plant species were able to maintain photosynthesis 7 d after placing in the offices. Parlour palm (Chamaedorea elegans), arrowhead plant (Syngonium podophyllum), peace lily (Spathiphyllum ‘Sensation’), and dumb cane (Dieffenbachia ‘Camilla’) had good performance throughout the experiment and were easy to grow. Off all tested Taiwan-native plant species, cast-iron plant (Aspidistra elaitor) had the highest photosynthetic rate. Other plant species, like bird’s nest fern (Asplenium nidus), Podocarpus macrophyllus, Schefflera arboricola, Ficus microcarpa ‘Golden Leaves’, and Nageia nagi also had higher photosynthetic rate, but should be placed at brighter sites. According to collected references and experimental results, we established data base of recommended indoor plantation and decoration examples. A booklet has been edited as House Plants Purify Indoor Air – Q&A. Three conferences on indoor plants improving air quality were held for promoting the knowledge and application of the topic.

indoor plants;carbon dioxide;formaldehyde