1.范围ISO 789的本部分规定了农业轮式拖拉机的正常和紧急转向模式的试验程序，该拖拉机至少有两个装有充气轮胎的车轴。它不适用于履带式或滑移式农业拖拉机。

1. ScopeThis part of ISO 789 specifies test procedures for normal and emergency steering modes of an agricultural wheeled tractor having at least two axles fitted with pneumatic tires. It does not apply to track-type or skid-steered agricultural tractors.