What type of air brake test must be performed before the relief crew can proceed with the train?

The Class 1 Initial Terminal and Road Air Brake Test is necessary before a relief crew can proceed with the train because it ensures that the air brakes are functioning properly after any changes in crew or prior to the train departing the initial terminal or starting a new segment of its journey. This test verifies that all components of the air brake system meet the required standards and that the air brakes are capable of providing adequate stopping power.

Conducting this test is crucial for safety; it confirms the operational integrity of the train’s braking system, which is essential for controlling the train when in motion. This aligns with regulatory and safety protocols that mandate thorough checks at the beginning of a journey, especially when a new crew takes over.

The other options involve different types of tests that serve specific purposes, but they do not replace the necessity of the Class 1 test before the relief crew can take control of the train.