A field survey on speech privacy in open-plan offices: Quantitative assessment of speech leakage during working hours

Open-plan offices are widely implemented due to their open design and facilitation of communication. However, their acoustic characteristics may pose challenges to speech privacy. This study aims to assess the current state of speech privacy in two offices through field investigations. Although the two offices have comparable room volumes, they differ significantly in occupancy levels, suggesting varying risks of speech leakage due to differences in seating density. The investigations included acoustic measurements in unoccupied rooms, noise level measurement, and sound recordings during working hours, as well as a questionnaire survey of office workers. Additionally, this study explored a quantitative approach to evaluating speech leakage using audio recordings collected during working hours. The results suggest that speech transmission is affected by seat density. Furthermore, a new method was proposed, employing speech recognition technology to quantitatively evaluate the extent of speech leakage from recorded workplace sounds. The effectiveness of this method was demonstrated, highlighting its potential for assessing speech privacy in real-world office settings. These findings underscore the importance of considering seating density and background noise in the design of open-plan offices to enhance acoustic environments and speech privacy.