ISO 13325:2003规定了在滑行条件下，即车辆或挂车处于自由滚动、无动力运行、变速器处于空档位置、发动机以及安全驾驶不需要的所有辅助系统关闭时，测量机动车或牵引挂车上安装的轮胎道路声发射的方法。

ISO 13325:2003 specifies methods for measuring tyre-road sound emissions from tyres fitted on a motor vehicle or towed trailer under coast-by conditions -- i.e. when the vehicle or trailer is in free-rolling, non-powered operation, with transmission in the neutral position and the engine as well as all auxiliary systems not necessary for safe driving switched off.