Improving prediction accuracy of chair absorption using scale model measurements

Accurate prediction of chair absorption is critical in room acoustic simulations, as seating significantly affects reverberation time. Several laboratory methods have been proposed to estimate the sound absorption coefficients of seating blocks based on a small number of chairs, including the ISO 354 methods in two editions, the Kath & Kuhl (K&K) method, and the perimeter-to-area (P/A) method by Bradley. However, there is currently no universally accepted standard measurement method for determining chair absorption, and the data quoted in the literature are not directly comparable because they are widely dispersed over time. This study evaluates the prediction accuracy of these four methods using 1/15-scale model measurements. Two additional modified methods are also considered. The validity of the laboratory methods is discussed in comparison with the in-situ measurement results in a model hall. The results show that the P/A method offers the most reliable predictions across various chair configurations. This work has been published in the J. Build. Eng., 98 (2024), 111483.