Int. J. Environmental Technology and Management, Vol. 22, Nos. 4/5, 2019 223 Copyright © 2019 Inderscience Enterprises Ltd. Quantitative analysis of sound absorption properties of plants in indoor environment for enabling sustainable practices Namrata Baruah* Studio Chintala, Bengaluru – 560038, India Email: Namrata.baruah42@gmail.com *Corresponding author Satyaki Sarkar, Bimal Chandra Roy and Rajan Chandra Sinha Department of Architecture, Birla Institute of Technology, Mesra, Ranchi – 835215, India Email: satyakisarkar@bitmesra.ac.in Email: bimalcroy@gmail.com Email: rajanchandrasinha@gmail.com Abstract: This paper showcases the results of the sound attenuation properties of some plants with a soil substrate for use as green sound absorbers in an indoor space. The plants used in this experiment were needed to survive in an indoor environment, hence only tropical, thermophilic plants which could grow in high humidity and warm temperatures with indirect sunlight were selected. An impedance tube of 100 mm dia. was used to calculate the direct incidence acoustic absorption coefficient of the plants and larger samples were tested within a reverberation chamber. The soil substrate used was a high porosity and low-density sample of perlite and coconut fibres. The results show that ferns and baby tears were good absorbers along with the soil substrate, whereas begonia was a better absorber at the lower and higher frequencies. The decibel drop by the fern with soil substrate is the highest with a decrease of frequency and the lowest is by Green Ivy which is due to morphological conditions. Keywords: sound absorption; indoor space; experiment; impedance tube; reverberation chamber; soil substrate; thermophilic plants; sound-absorption coefficient; decibel drop; sustainable plant usage. Reference to this paper should be made as follows: Baruah, N., Sarkar, S., Roy, B.C. and Sinha, R.C. (2019) ‘Quantitative analysis of sound absorption properties of plants in indoor environment for enabling sustainable practices’, Int. J. Environmental Technology and Management, Vol. 22, Nos. 4/5, pp.223–235. Biographical notes: Namrata Baruah is an Architect from the Birla Institute of Technology, Mesra, Ranchi, India and is currently working as a Project Architect in the Studio Chintala, Bengaluru – 560038, India. Satyaki Sarkar is an Architect and Urban Planner and is currently working as an Associate Professor in the Department of Architecture, Birla Institute of Technology, Mesra, Ranchi – 835215, India.