Which action is correct when parking an air-braked vehicle?

Which action is correct when parking an air-braked vehicle?

• A. Rely on service brakes to hold the vehicle
• B. Apply the parking brake when the vehicle is parked
• C. Turn off the engine and release the brakes
• D. Park without using the parking brake on a hill

Answer: (B)

When parking an air-braked vehicle, the parking brake is the mechanism that actually holds the vehicle in place after you stop. Unlike the service brakes, which rely on air pressure to slow and stop the vehicle, the parking brake is designed to stay engaged even when you’re not actively pressing the brake pedal. Air lines can develop leaks or lose pressure, especially after shutdown, so relying on the service brakes to hold the vehicle is unsafe. Therefore, you apply the parking brake when the vehicle is parked. This ensures the brakes stay applied and the vehicle remains stationary, even on grades. On a hill, you’d also take extra precautions like using wheel chocks if available, but the essential step is to engage the parking brake. Turning off the engine and releasing the brakes would remove the holds that keep the vehicle from moving, which defeats the purpose of the parking brake. Relying on the service brakes to hold the vehicle is not reliable for long-term stopping, and parking without using the parking brake on a hill is asking the vehicle to roll, which is unsafe.

When parking an air-braked vehicle, the parking brake is the mechanism that actually holds the vehicle in place after you stop. Unlike the service brakes, which rely on air pressure to slow and stop the vehicle, the parking brake is designed to stay engaged even when you’re not actively pressing the brake pedal. Air lines can develop leaks or lose pressure, especially after shutdown, so relying on the service brakes to hold the vehicle is unsafe.

Therefore, you apply the parking brake when the vehicle is parked. This ensures the brakes stay applied and the vehicle remains stationary, even on grades. On a hill, you’d also take extra precautions like using wheel chocks if available, but the essential step is to engage the parking brake.

Turning off the engine and releasing the brakes would remove the holds that keep the vehicle from moving, which defeats the purpose of the parking brake. Relying on the service brakes to hold the vehicle is not reliable for long-term stopping, and parking without using the parking brake on a hill is asking the vehicle to roll, which is unsafe.