ISO 11819-2:2017规定了在轮胎/道路噪声占主导地位的情况下，评估不同路面对交通噪声影响的方法。对结果的解释适用于在基本平坦的道路上以40 km/h及以上的恒定速度行驶的自由流动交通，在这种情况下，假设轮胎/道路噪声占主导地位（尽管在一些国家，当重型车辆比例较高时，轮胎/道路噪声可能在40 km/h时不占主导地位）。 对于交通不自由流动的其他驾驶条件，例如在交叉口或高加速度下，以及交通拥挤的情况，路面对噪声排放的影响更为复杂。对于纵坡较高且重型车辆比例较高的道路也是如此。 比较路面噪声特性的标准方法为道路和环境主管部门提供了一种工具，用于确定符合特定噪声标准的路面使用的常规做法或限制。 然而，提出此类标准不在本文件的范围内。 ISO 11819-1定义了另一种方法:统计传递（SPB）方法。本文件中规定的近距离（CPX）方法与SPB方法具有相同的主要目标，但旨在专门用于补充该方法的应用，例如: -几乎任何任意场地的路面噪声特性，主要目的是检查是否符合表面规范（参考文献[1]中建议了生产一致性的示例）； -检查维护和状态的声学效果，例如表面的磨损和损坏，以及堵塞和多孔表面的清洁效果； -检查路段的纵向和横向均匀性； -开发更安静的路面和研究轮胎/道路相互作用。 注:本文件不描述CPX法测量的正式应用条件。此类条件可在其他标准或法律文本中定义。 然而，关于ISO 11819-1和本文件适用性的建议见附录D。 与SPB法相比，CPX法的测量速度更快、更实用，但仅在轮胎/道路噪声占主导地位且动力装置噪声可以忽略的情况下，CPX法的测量更为有限。此外，它不能像SPB方法那样充分考虑重型车辆轮胎/道路噪声，因为它使用轻型卡车轮胎作为重型车辆轮胎的替代品，并且没有考虑动力装置噪声。 本文件中规定的CPX方法旨在测量路面的性能，而不是轮胎的性能。如果该方法用于研究目的，以提供轮胎之间差异的指示，则载荷和充气通常会调整为本文件规定之外的其他值。

ISO 11819-2:2017 specifies a method of evaluating different road surfaces with respect to their influence on traffic noise, under conditions when tyre/road noise dominates. The interpretation of the results applies to free-flowing traffic travelling on essentially level roads at constant speeds of 40 km/h and upwards, in which cases tyre/road noise is assumed to dominate (although in some countries it is possible that tyre/road noise does not dominate at 40 km/h when the proportion of heavy vehicles is high). For other driving conditions where traffic is not free-flowing, such as at junctions or under heavy acceleration, and where the traffic is congested, the influence of the road surface on noise emission is more complex. This is also the case for roads with high longitudinal gradients and a high proportion of heavy vehicles. A standard method for comparing noise characteristics of road surfaces gives road and environment authorities a tool for establishing common practices or limits as to the use of surfacings meeting certain noise criteria. However, it is not within the scope of this document to suggest such criteria. ISO 11819-1 defines another method: the statistical pass-by (SPB) method. The close-proximity (CPX) method specified in the present document has the same main objectives as the SPB method, but is intended to be used specifically in applications that are complementary to it, such as: - noise characterization of road surfaces at almost any arbitrary site, with the main purpose of checking compliance with a surface specification (an example for conformity of production is suggested in Reference [1]); - checking the acoustic effect of maintenance and condition, e.g. wear of and damage to surfaces, as well as clogging and the effect of cleaning of porous surfaces; - checking the longitudinal and lateral homogeneity of a road section; - the development of quieter road surfaces and research on tyre/road interaction. NOTE This document does not describe the conditions of application for formal purposes of the measurement with the CPX method. Such conditions may be defined in other standards or legal texts. However, suggestions for the applicability of ISO 11819-1 and this document are provided in Annex D. Measurements with the CPX method are faster and more practical than with the SPB method, but are more limited in the sense that it is relevant only in cases where tyre/road noise dominates and power unit noise can be neglected. Furthermore, it cannot take heavy vehicle tyre/road noise into account as fully as the SPB method can, since it uses a light truck tyre as a proxy for heavy vehicle tyres and does not take power unit noise into account. The CPX method specified in this document is intended to measure the properties of road surfaces, not the properties of tyres. If the method is used for research purposes, to provide an indication of differences between tyres, the loads and inflations would normally be adjusted to other values than specified in this document.