Prediction of open plan office acoustics.

Open plan office users complain of two annoyances due to noise. The first annoyance is lack of concentration and the second annoyance is the reduction of the confidentiality of conversations. The rapid prediction of the acoustic work environment in open plan offices would give the possibility to optimize the acoustic comfort of the users during the design phase of the construction.
To begin with, the calculation methods used by CSTB have been validated. For this, the efficiency of an acoustic table screen between two working desks by taking into account the acoustic properties of the ceiling has been studied. Since the desks are positioned in an open plan office, it can be assumed that the floor and the ceiling are of infinite extent. In this study the floor and ceiling are modeled as two parallel baffles in the BEM method MICADO3D. The ray-tracing simulation program ICARE has been used with the Capolino and Albani method along with double edge scattering. A comparison with the measurements done in the semi-anechoic chamber of INRS will be presented.
The MEPAS project, a common 2-year project between INRS and CSTB funded by ANSES, aims to develop a rapid calculation method for the prediction of open plan office acoustics. This part of the paper presents the work realized in the MEPAS project at mid-term. Fictive open plan office models have been created and simulated with ICARE and MICADO3D. Real open plan offices are investigated by creating a model for acoustic simulations and measurements. In each office different acoustic criteria such as the spatial decay rate of speech D2,S or the privacy radius rp (NF EN ISO 3382-3) are calculated and measured.