How should the lap belt be positioned for safety?

The lap belt should be positioned over the pelvis to ensure maximum safety in a vehicle. This position helps to effectively distribute the forces experienced during a collision across the stronger parts of the body, which can reduce the risk of injury. When the lap belt is positioned correctly, it sits snugly across the hips and pelvic area, minimizing the risk of sliding under the belt in an accident, a phenomenon known as "submarining."

In contrast, placing the lap belt over the abdomen can lead to serious internal injuries in the event of a crash, as this area is more vulnerable. Positioning it under the arm or across the chest can also be dangerous; these placements can interfere with the proper functionality of the seatbelt system and may not provide adequate restraint. Therefore, positioning the lap belt over the pelvis is essential for effective restraint and safety in the vehicle.