Conference_programme: 18.4 - Office noise : psychological effects and room acoustic design

Lecture: A ground study for the evaluation of sound masking in open-plan spaces

Author(s): Chevret Patrick, Lenne Lucas

Summary:
Today's sound masking systems are presented as tools for reducing noise disturbance in open-plan offices. These systems comprise loudspeakers that artificially increase background noise to curtail speech intelligibility and, according to their manufacturers, they curb disturbance and cognitive fatigue. These arguments are based on studies, whose representativeness remains limited since it is based only on laboratory experiments involving short exposure times. It is this lack of representative data that justifies the present study, whose aim is to evaluate in situ the effects of a masking system on different psychological states (fatigue, stress, mental workload) and on noise disturbance. To fulfil this aim, an off-the-shelf sound masking system was selected on technical criteria such as the possibility of generating a uniform acoustic field in the room or the possibility of automatically adjusting the emitted level to the surrounding noise level. The system was installed for several weeks in an open-plan office at a major French banking corporation. Two types of measurement were taken throughout the system implementation period. (1) Objective measurements: room acoustic performance characteristics were recorded (spatial decay of sound level - D2,S and DL2 – and reverberation time) as well as ambient noise at different system operating moments. (2) Subjective measurements using questionnaires. These subjective measurements allowed us to evaluate the effects of sound masking on aforementioned different psychological states. The effects revealed by analysing the questionnaire replies will be presented at the conference.

Corresponding author

Name: Dr Chevret Patrick

e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Country: France