Validation of a method to predict speech privacy in a diversity of office environments.
Status: Completed
Funding Sources: CBE Industry Consortium
Project Objective
Conduct a field study of acoustical conditions in office environments to test an industry-wide speech privacy prediction model. Use the findings of this analysis to suggest changes and/or modifications to the model as necessary.
Significance to Industry
Occupant surveys administered by CBE typically find that acoustics is the leading source of workplace dissatisfaction. This acoustic dissatisfaction is frequently related to speech privacy—overhearing unwanted conversations, or feeling that one is overheard. In one study of seven office buildings, as many as 72% of respondents were dissatisfied with speech privacy in their workplace.
A speech privacy prediction model suitable for today’s open-plan workspaces would be valuable to architects, interior designers, and facility professionals, helping them to avoid costly mistakes when designing or furnishing workplaces. Forty years ago, W. J. Cavanaugh and his associates developed a practical model for predicting the acceptability of speech privacy in enclosed office environments. Acoustical engineering firms have used modified versions of this Speech Privacy Prediction model for design purposes, and found it to be a valuable tool. Since Cavanaugh developed this model, offices have been transformed by the introduction of cubicles with varying-height partitions. However, the model had not been formally tested and validated in the context of today’s offices, and this needed to be done before the model could become widely adopted as a design tool.
Research Approach
The Speech Privacy Predictor (SPP) was evaluated in offices with partitions, telephones/speakerphones, common areas, team spaces, and widespread use of computers. Both open-plan and private offices were tested, and their physical characteristics carefully described. We conducted occupant surveys to identify and characterize acoustical problems in each office configuration. The measured data was used to assess whether the complaints would have been predicted given the architectural design and the acoustical attributes of the office environments.
We found that the measured results correlated closely with predicted results, and that actual survey results and anecdotal comments corresponded with what the SPP analytic procedure predicted. The final report is now available and linked below.
Publications and Reports
Salter, C., K. Powell, D. Begault, and R. Alvarado, 2003. Case Studies of a Method for Predicting Speech Privacy in the Contemporary Workplace. CBE Summary Report, January.