ACOUSTICAL PERFORMANCE AND COMFORT DEMANDS OF MRT TRAINS

Abstract

The Mass Rapid Transport (MRT) in Singapore is a highly frequented facility, reportedly to have 1.6 million of ridership per day. For every ride, commuters are exposed to announcements necessary for communication, safety or even mass communication as well as background noise created by the train, interaction with the tracks, or by commuters themselves. With a focus on the acoustics mandate in MRT trains, this dissertation aims to assess the audibility of the Public Address (PA) System with the hypothesis that the presence of background noise has a correlation with its performance. It also seeks to find out the acceptability or comfort demands of commuters, henceforth providing recommendations for improvements after a review. An integrated objective and subjective methodology was approached using A weighted Sound Pressure Level to find Signal-to-Noise ratio as well as background noise to correlate with the subjective opinions of commuters. It was found that psycho-acoustics is complex and hence no strong factors were found directly related to acoustic performance or comfort. Nevertheless, this dissertation highlights some factors which may affect a perceived acoustical performance and comfort level such as the presence of variable noise control in a train, the type of tracks it is running over, conversation factors, one’s threshold for noise, acoustic privacy and preferences. Recommendations are given in light of the context of results gathered. The findings should be read with an understanding of limitations such as possible infringement of commuters’ privacy if a concurrent objective and subjective test were to be carried out, assumptions made and a lack of established standards. Although a pioneer research on the acoustic mandate in MRT trains, a basic understanding from this dissertation with future follow-up is likely to bring about an optimistic standard of acoustics in Singapore’s rail transport.