Field study of signal and guide sound for the elderly in subway station

This study conducted surveys and field measurements in order to investigate the signal and guide sound in the subway station from the perspective of the elderly. In general, there are signal and guide sounds for informing train arrival and departure, escalator, elevator, ticket box, and audio guidance system for blind people in Korean subway stations. A survey was first conducted and 84 elderly persons aged over 60 participated. Questionnaire consists of questions about noise and reverberance in the subway station, and intelligibility and loudness of signal and guide sound using 5 points bipolar scale. Results showed that response for noise and reverberance ranged from 3.2 to 3.3 point (average value), and averaged value of response for intelligibility and loudness of signal and guide sound was 3.1 point. It was also shown that noise needs to be improved the most. In addition, measurements for train arrival noise, signal and guide sound, and background noise were conducted at four subway stations. Those were measured at a position below sound speakers near to the center of the platform. Result showed that the S/N (signal to noise) ratio between signal sound and background noise ranged from 5.7 dBA to 19.2 dBA. It was also found that the range of the S/N ratio between announcement and train arrival noise was from -2.4 dBA to 8.4 dBA. These measured S/N ratios were discussed from the perspective of elderly person's information cognition and influence of noise and reverberance in platform and concourse on S/N ratio was also discussed.