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 and engage parking brake
• D. Place cones around the vehicle

Answer: (B)

When a vehicle carrying explosives is parked on a grade or ramp, the immediate safety goal is to prevent any movement. Wheel chocks provide a positive mechanical restraint by pressing against the tires and the ground, creating a solid block that stops the vehicle from rolling even if the brakes fail or the slope exerts force. This physical barrier is essential on inclines because relying solely on the parking brake or turning off the engine does not guarantee immobilization in a sloped position. Placing cones around the vehicle helps with visibility and exclusion zones, but it does not prevent movement. So the required action is to chock the vehicle to keep it from moving.