During the air brake system warning light and buzzer test, an alarm should sound before the pressure drops below what value?

The alarm for the air brake system warning light and buzzer is designed to activate to alert the driver of low air pressure before it drops to a critical level. This safety feature is crucial for ensuring that the air brake system functions effectively. The correct value at which the alarm should sound is 60 psi (414 kPa).

This threshold is set to give the driver adequate warning to take corrective action before pressure falls to a point where the brakes could fail, ensuring safety during operations. Operating air brake systems rely on maintaining sufficient pressure; therefore, the warning system is calibrated to activate at 60 psi to prevent hazardous situations. It serves as a crucial early warning indicator so that the driver can address potential issues before reaching the dangerously low pressure levels that could impair braking effectiveness.