An engineering method to measure the impact sound reduction due to soft coverings on heavyweight floors

In order to measure the improvement of impact sound insulation ΔL due to a floor covering in accordance with ISO 10140 standard, a specialised measurement facility is required. As a consequence, such measurements become fairly expensive and available only to those who have access to a specialised laboratory. Therefore, the authors propose an engineering method to measure the ΔL value in the case of soft coverings placed on heavyweight floors. This method enables the replacement of extensive test facilities with one room with a heavyweight floor and a mobile insulation case inside. The inside of the case acts as a source room; the tapping machine and the test sample are placed inside the case, which separates the airborne sounds from the structure borne sounds. The measurement procedure described in ISO 10140 standard is adopted - ΔL is determined by the difference between the sound level outside the case with and without the test sample. In this article, the proposed engineering method is thoroughly delineated and verified with theoretical and energy (SEA) analyses. Next, the results of experimental tests are presented - the reduction of impact sound on four different groups of samples measured in three different rooms. The obtained results are compared with the corresponding ΔL values measured according to ISO 10140 standard. This comparison shows a very strong convergence between the curves of impact sound reduction obtained by both methods. Based on all the above findings, it is stated that the presented engineering method enables accurate measurements of impact sound reduction of heavyweight floors due to soft coverings within the range of uncertainty and application. Due to the reduced measurement facilities in comparison with the ISO standard, the engineering method can be a useful tool in the process of designing and improving products such as soft floor coverings.