State of field measurement of facade sound insulation in buildings: evaluation of proficiency testing data according to ISO 140-5:1998

The ISO 140-5:1998 standard specifies the testing methods to evaluate the sound insulation in buildings and building elements for facades. Three rounds of a proficiency testing scheme for airborne sound insulation measurements have been performed according to the methods specified in the standard for a whole facade by using an external loudspeaker as the noise source. The adequacy of the intercomparison is guaranteed by means of the assessment of global precision criteria in compliance with the scope stipulated by the normative references in order to determine the reproducibility limits in a regulated measurement method. To evaluate the participant performance, the corresponding combined scores as composite indexes are calculated, so if this assessment is performed along a certain number of rounds, it will remark the participants that show an overall satisfactory performance by monitoring their achievement over time. Therefore, in order to establish a reference value in terms of precision level, an approach based on the development of a collaborative test in controlled conditions is proposed. The goal is to provide reliable and updated criteria for the evaluation of repeatability and reproducibility limits in this field, particularly in those scopes in which nowadays there is no normative reference or this is very poor. Furthermore, these prescribed values of precision should be verifie