What does a 'leakage test' assess in the air brake system?

The leakage test is designed specifically to evaluate the rate at which air escapes from the air brake system. This assessment is crucial because the integrity of the air brake system heavily depends on maintaining air pressure. If there are leaks, it can lead to inadequate pressure levels, which directly affects the performance and safety of the braking system. By determining the rate of air loss, maintenance personnel can identify and address issues before they impact the operational efficiency and safety of the train. Thus, the leakage test serves as a vital diagnostic tool to ensure that the air brake system maintains the necessary air pressure to function effectively.