Illinois CDL Practice Exam

The primary purpose of using a seat belt in a commercial vehicle is to protect the driver and passengers in the event of an accident. Seat belts significantly reduce the risk of serious injury or death by keeping occupants securely in their seats during crashes or sudden stops. They help prevent ejection from the vehicle, which can happen in the case of a severe impact.

While comfort, avoiding traffic violations, and vehicle stability are relevant considerations in driving, they do not encompass the critical safety role that seat belts play. Comfort may be enhanced by the use of seat belts, but that is not their main function. Avoiding traffic violations could be a consequence of wearing a seat belt, as it is often a legal requirement; however, this is secondary to the safety aspect. Similarly, while properly secured occupants can help maintain stability during a vehicle's movement, the primary and most essential reason for seat belts is the protection they offer during collisions.