A safety belt system that has won great praise for automatically strapping in drivers is drawing scrutiny from safety experts who say the belts are often misused in a way that can be dangerous or even fatal. The system consists of a motorized shoulder belt and a manual lap belt.

New Hampshire is the only state that has no enforceable laws for the wearing of seat belts in a vehicle.

Though more awkward for vehicle occupants, most manufacturers opted to use less expensive automatic belts rather than airbags during this time period. When driver side airbags became mandatory on all passenger vehicles in model year 1995, most manufacturers stopped equipping cars with automatic seat belts.

The term “passive restraint” refers to a vehicle safety device or feature that is activated by the force of a collision or sudden stop with the intention of preventing injury to the occupant. The most common passive restraint systems in vehicles today are airbags and seat belts, or safety belts.

Nils Bohlin

Seat belts stop you tumbling around inside the car if there is a collision. However, they are designed to stretch a bit in a collision. This increases the time taken for the body’s momentum to reach zero, and so reduces the forces on it.

They increase the time taken for the change in momentum on the occupants’ bodies, and so reduce the forces involved and any subsequent injuries. They increase the time taken for the change in momentum on the occupants’ bodies, and so reduce the forces involved and any subsequent injuries.

Crumple zones work by managing crash energy and increasing the time over which the deceleration of the occupants of the vehicle occurs, while also preventing intrusion into or deformation of the passenger cabin. This better protects car occupants against injury.