Equipment for noise reduction in road traffic. Test method for determination of acoustic performance. Part 5: Intrinsic characteristics. In-situ acoustic absorption in direct field acoustic conditions

This technical specification establishes a comprehensive framework for evaluating the acoustic performance of devices designed to mitigate noise generated by road traffic. Specifically focusing on the fifth segment of a broader series, it addresses the measurement of intrinsic characteristics under direct field conditions. The document outlines precise methodologies for conducting in-situ assessments of sound absorption capabilities within the immediate vicinity of the device installation. These procedures are critical for ensuring that the physical components effectively attenuate noise propagation as intended. The approach details the necessary experimental setups and measurement protocols required to determine the inherent absorption properties without external interference. By adhering to these defined steps, manufacturers and testing facilities can reliably quantify the effectiveness of noise reduction barriers in real-world environments. The methodology ensures consistency in data collection, allowing for accurate comparisons between different products and designs. This standard provides a unified reference for assessing how well specific materials and structures absorb sound directly in the path of traffic noise, contributing to a systematic understanding of acoustic performance metrics.