How should wheel chocks be used to prevent movement when parked?

• A. Place only behind wheels
• B. Do not use chocks
• C. Use chocks only on inclines
• D. Place on both sides of the wheels to prevent movement when parked.

Answer: (D)

Wheel chocks are used to prevent a parked vehicle from moving by blocking the wheel from turning. The safest and most effective approach is to place chocks on both sides of the wheels so the wheel is blocked in either direction. This ensures the vehicle can’t roll forward or backward, even if a force is applied or a chock slips slightly. It’s important to use chocks in addition to applying the parking brake and to place them against the wheel and the ground on solid footing.

Relying on chocks behind the wheels alone isn’t enough because the wheel could still move in the opposite direction. Using chocks only on inclines leaves wheels free to move on level ground or if pushed from the other side. Not using chocks at all is unsafe.