New Jersey Air Brakes Practice Test

An air brake system is considered fully charged at what psi?

1. 100 psi

2. 110 psi

3. 125 psi

4. 150 psi

The correct answer is: 125 psi

An air brake system is considered fully charged at 125 psi. This means that the air compressor has filled the air tanks to this pressure, which allows the braking system to function effectively. At 125 psi, the air brake system has enough air to sufficiently engage the brakes, ensuring that they work properly when needed. This pressure level is a standard setting across many commercial vehicles, providing consistent performance and safety. While other pressure levels like 100 psi, 110 psi, and 150 psi may be relevant in specific contexts or systems, 125 psi is the commonly recognized threshold that indicates the air brake system is adequately prepared for operation. An understanding of this pressure is vital for drivers and mechanics to ensure that air brake systems are functioning correctly and to avoid potential malfunctions that could lead to safety issues on the road.