What is an 'air brake test'?

Answer: B — procedure to ensure the air brake system is functioning correctly before departure

An 'air brake test' is a procedure conducted to ensure that the air brake system is functioning correctly before a train departs. This test is crucial for operational safety, as it verifies that all components of the air brake system are working as intended and that the brakes can respond appropriately when engaged. During the test, operators will check for leaks, confirm proper pressure levels, and assess the overall responsiveness of the brakes to ensure they meet safety standards. This ensures that both the crew and passengers are safe during the journey, as reliable brakes are essential for stopping the train effectively under various conditions. Other options, while related to brake maintenance and training, do not specifically address the purpose and implementation of the air brake test itself, which is fundamentally about verifying the system's operational readiness prior to train movement.