Vehicle Inspection, Brakes, and School Bus Safety Equipment
Pre-trip inspection
This domain tests inspection, brake checks, and safety equipment. A pre-trip inspection is a systematic walk-around and operational check, not just a light check. Verify tires, wheels, lug nuts, brakes, steering, suspension, exhaust, mirrors, stop arm, crossing arm, flashing lights, door, emergency exits, seats, belts, fire extinguisher, first aid kit, and radio. Test the horn and wipers. Check for fluid leaks and secure compartment latches. Report defects and do not operate an unsafe bus.
Brake tests
For air brakes, build pressure to governor cut-out, shut off the engine, and watch the gauge. With brakes released, loss should not exceed 2 psi in one minute; with the service brake fully applied, loss should not exceed 3 psi in one minute. The low-pressure warning should activate by 60 psi, and spring brakes should set in the 20–45 psi range. Know your bus: hydraulic brake buses require a different check. Test the parking brake and service brake for holding and stopping.
Safety equipment
Confirm the stop arm extends fully, red lights flash, crossing arm moves, and the door operates. Check the fire extinguisher gauge and mounting, first aid kit contents, emergency exit operation, and belt condition. Ensure the two-way radio works and emergency numbers are posted.
Worked example
With the engine off and full pressure, the gauge drops 4 psi in one minute with brakes released. That exceeds the 2 psi limit, so the bus fails the leak test. Do not drive it; tag it out and report the defect. A small leak can become a brake emergency with students aboard.
Traps that cost marks
Do not rely on a walk-around alone. Do not skip the stop arm, crossing arm, or emergency exits. Do not ignore a low-air warning or a gauge that falls quickly. Do not assume a hydraulic bus uses the same leak-test numbers as an air brake bus.