本技术规范规定了用于屏蔽铁路噪声的室外隔音屏障插入损耗的测定方法。它规定了现场测量屏障插入损耗的详细程序，包括传声器位置、源条件和测量场地的声环境。本技术规范允许测量给定现场（包括给定气象条件）给定声屏障的插入损耗。它无法比较不同位置的等效屏障的插入损耗值。它可以用“直接法”在给定气象条件下比较同一地点不同类型屏障的插入损耗值。本技术规范给出了一种确定插入损耗的方法: 安装隔音屏障前后的水平差（“直接法”）；如果直接法不适用，因为已经安装了屏障，则在安装屏障之前，通过在另一个被判定为等效的现场进行测量，使用“间接法”估计声压级。对于同等场地，需要在声源特征、话筒位置、地形剖面、地表特征、周围人工结构和气象条件方面进行密切匹配。本技术规范规定了确保在“之前”和“之后”情况下保持充分等效条件的原则，以允许对屏障插入损耗进行确定、可靠和可重复的测定。本技术规范不包括屏障固有声学特性的测定，例如隔声指数和吸声系数。 等效连续A加权声压级和三分之一倍频程声压级用作噪声描述符。本技术规范可用于屏障性能的常规测定或工程或诊断评估。它可用于即将安装或已经安装屏障的情况。交叉引用:EN 60942IEC 60942EN 61260IEC 61260EN 61672-1IEC 61672-1ISO/IEC指南98-3GUM:1995EN 16272-3-1EN 16272-3-2ISO 9613-1购买本文件时可提供的所有当前修订版均包含在购买本文件中。

This Technical Specification specifies methods for the determination of insertion loss of outdoor noise barriers intended to shield railway noise. It specifies detailed procedures for in situ measurement of barrier insertion loss including microphone positions, source conditions and acoustic environments of the measurement sites.This Technical Specification allows one to measure the insertion loss of a given noise barrier at a given site including given meteorological conditions. It does not make it possible to compare insertion loss values of an equivalent barrier at a different site. It can be used for comparing insertion loss values of different types of barriers at the same site under given meteorological conditions by the "direct method". This Technical Specification gives a method for determining insertion loss:from the level difference before and after the installation of noise barriers (the "direct method");when the direct method is not applicable, because a barrier has already been installed, using an "indirect method" to estimate the sound pressure levels before installation of the barrier by measurement at another site which has been judged to be equivalent.For equivalent sites, a close match is required in source characteristics, microphone locations, terrain profiles ground surface characteristics, surrounding artificial structures and meteorological conditions. This Technical Specification prescribes principles for ensuring that sufficiently equivalent conditions are maintained between "before" and "after" cases to permit certain, reliable and repeatable determination of barrier insertion loss.This Technical Specification does not cover the determination of the intrinsic acoustic characteristics of the barrier, for example the sound insulation index and the sound absorption coefficient.The equivalent continuous A-weighted sound pressure level and one-third-octave band sound pressure level are used as noise descriptors.This Technical Specification can be used for routine determination of barrier performance or for engineering or diagnostic evaluation. It can be used in situations where the barrier is to be installed or has already been installed.Cross References:EN 60942IEC 60942EN 61260IEC 61260EN 61672-1IEC 61672-1ISO/IEC Guide 98-3GUM:1995EN 16272-3-1EN 16272-3-2ISO 9613-1All current amendments available at time of purchase are included with the purchase of this document.