ISO 18211:2016规定了一种对碳钢和低合金钢地上管道和工厂管道进行远程测试的方法，该方法使用在整个环形管段上施加轴向传播的引导超声波，以检测腐蚀或侵蚀损伤。 导波测试（GWT）方法允许快速检查地面管道、工厂管道和有套管的道路交叉口，对可能的腐蚀和侵蚀区域进行定性筛选和定位。GWT通常在运行的管道系统上进行。 ISO 18211:2016适用于以下类型的管道: a） 地上涂漆管道； b） 地上绝缘管道； c） 涂漆的工厂管道； d） 绝缘设备管道。 注:带有外部套管（无沥青或塑料涂层）的道路交叉口内的管段是埋地管道的特殊情况，管道外径上没有土压力。ISO 18211:2016适用于这些有外壳的道路交叉口。 由于复杂性增加，上述列表中未包括的其他类型的管道需要专用方法。

ISO 18211:2016 specifies a method for long-range testing of carbon and low-alloy steel above-ground pipelines and plant piping using guided ultrasonic waves with axial propagation applied on the entire circumferential pipe section, in order to detect corrosion or erosion damage. The guided wave testing (GWT) method allows for fast inspection of above-ground pipelines, plant piping and cased road crossings, giving a qualitative screening and localization of probable corroded and eroded areas. GWT is typically performed on operating piping systems. ISO 18211:2016 is applicable to the following types of pipes: a) above-ground painted pipelines; b) above-ground insulated pipelines; c) painted plant piping; d) insulated plant piping. NOTE Pipe sections within road crossings with external casings (without bitumen or plastic coating) are a special case of buried pipe where there is no soil pressure on the OD of the pipe. ISO 18211 :2016 applies to these cased road crossings. Other types of pipes not included in the above list need dedicated approaches due to increased complexity.