When must a Class 1 air brake test be conducted?

A Class 1 air brake test must be conducted when the train travels more than 3,000 miles. This requirement ensures that the brakes are functioning correctly and safely, especially after long distances, which can put strain on brake systems. By performing this test after extensive travel, it helps to ensure the continued safety and reliability of the train's braking system, minimizing the risk of brake failure.

Other situations, such as crew changes or interchanges, may necessitate different types of brake tests, but the specific requirement for a Class 1 test is directly tied to the distance traveled. This comparison underscores the importance of regularly scheduled maintenance and inspections in the operational protocols of train safety.