The Acoustic Comfort in Open Plan Offices, Case Study on a True Office

Abstract

Open-plan offices are normally noisy working places. In this study, an acoustical evaluation of a real open-plan office was performed. Ambient noise and reverberation time were measured. Sound pressure levels of 64.9-67.2 dB(A) were determined, with noise mostly within the frequency range of 500 to 2000 Hz, which is typical of human speech. Reverberation times of 1.25, 1.31, and 1.29s were detected for the frequencies of 500, 1000, and 2000 Hz, respectively. Both sound pressure levels and reverberation times are too high. Optimal values for sound pressure levels are in the range of 45 to 65 dB(A), while reverberation time values should be below 0.5 s for the frequencies of 500, 1000, and 2000 Hz. After the evaluation, acoustical improvements to the office were suggested. These improvements would be able to reduce sound pressure levels by 5.6 dB, and reverberation time down to 0.3s, both in the frequency of 1000 Hz. After the acoustical treatment, new measurements confirmed the adequacy of the acoustical design.