Evaluation of impact sound in the field situation - research at Lund University

During the last years work has been carried out in collaboration between Lund University, WSP Acoustics and the Royal Institute of Technology (KTH) in Stockholm, to bring more basis for impact sound evaluation in the field situation. Results from this study so far, indicate that current international (ISO 717) method is unsatisfactory, and improvements are probably necessary. In this paper we discuss the results and propose new proper ways to evaluate impact sound, either by using single numbers and adaptation terms (modified or not modified) according to the international standard ISO 717/2 or by specifying new rules (modified single number rating) for evaluation. Furthermore, in this work we imply that the ISO impact sound source is an acceptable sound source simulating footstep and other impact sounds in a dwelling. Our study includes both evaluation from former investigations and new objective measurements and interviews with tenants. The latest results added are derived from modern housing design. Modern housing design differs a lot from earlier design, which seems to cause phenomenon that further complicate the use of prior standard evaluation methods