During the air leak test, how much psi should you not lose after holding the brake for one minute?

In the context of the air leak test during a pre-trip inspection, it is critical to determine how much air pressure should be maintained to ensure the braking system is functioning properly. The correct answer specifies that the vehicle should not lose more than 3 PSI after holding the brake for one minute. This standard is in place to guarantee that the brake system is sufficiently airtight, which is vital for the safety and effectiveness of the braking system.

A loss of air pressure greater than 3 PSI could indicate a potential leak in the air system, which may compromise the braking performance. This threshold allows for a small amount of normal fluctuation while ensuring that any significant issues are promptly identified. Thus, maintaining air pressure within these limits is essential for safe operation of the vehicle.

When it comes to the other choices, losing no more than 1 PSI would be an excessively stringent standard that is not typically required in real-world applications; most systems have a tolerance level that accounts for minor loss due to normal wear and tear. Meanwhile, a loss of 5 PSI or 10 PSI would be indicative of more serious air system leaks, which could impair braking performance and potentially endanger safety. Establishing a limit of no more than 3 PSI strikes a balance between safety and