At what pressure does the audible alarm sound on an air brake system?

The audible alarm in an air brake system typically sounds at a pressure of 60 psi. This is an important safety feature designed to alert the driver of a vehicle when the air pressure falls below a certain threshold, indicating that the braking system may not be operating effectively. If the pressure drops to this level, it serves as a warning that the driver should take action to either build the pressure back up or stop the vehicle safely. Understanding this threshold helps ensure that drivers maintain proper air pressure in their brake systems, crucial for safe vehicle operation. Awareness of this alarm is vital for anyone operating vehicles equipped with air brake systems, as it can prevent potential brake failure and enhance overall safety on the road.