Seat belts are known for their life-saving attributes. Restricting the amount of force with which occupants strike a vehicle's interior during an accident results in a reduction of the number of fatalities and the severity of injuries. In addition, seat belts help prevent ejections from a vehicle involved in an accident. As such, the control of the potential projectile action that victims are subjected to in a crash results in lifesaving and injury-reducing effects. NHTSA has estimated that seat belts are effective in reducing fatalities in the neighborhood of 40-50 percent. A lap/shoulder belt has an effectiveness of 41 percent. This means that for every 100 nonusers of this device that are killed, 41 would have avoided death if they had worn the lap/shoulder belt. An airbag together with a lap/shoulder belt is estimated to have an effectiveness of 46 percent. In addition, the effectiveness of a shoulder belt is 29 percent, a lap belt (rear seats) is 18 percent, and an airbag only is 17 percent. The lap/shoulder belt in conjunction with the airbag saves the most lives.
The potential effect of seat belts is mitigated by the lack of use of seat belts by the motoring public. As such, seat belt laws have been instituted in many states. Usage rates generally increase with the advent of a seat belt law and decline after some initial period of time, but not to the prelaw rate. The question next becomes, are the seat belt laws effective? By and large, they are indeed capable of reducing fatality rates and various types of injury rates.
Basically, two different types of seat belts laws, otherwise referred to as mandatory usage laws, have been applied by the states initiating such laws. These are primary and secondary laws...............
