What must be accomplished when parking an explosive laden vehicle on a grade or ramp?

• A. Set the parking brake
• B. Chock the vehicle
• C. Turn off ignition
• D. Place warning cones

Answer: (B)

On a grade or ramp, gravity makes the vehicle prone to rolling, so the key safety step is to physically prevent wheel movement. Chocking the wheels places solid blocks against them to stop any potential motion, providing a independent restraint that doesn’t rely on the braking system or engine. Even if the parking brake is set or the engine is off, a vehicle on a slope could still move if brakes fail or if the vehicle settles; chocks prevent that risk. Turning off the ignition eliminates the engine but does not immobilize the vehicle, and placing warning cones helps visibility but does not stop movement. For an explosive-laden vehicle, securing it with wheel chocks is the essential action to prevent dangerous movement.