Automotive safety reached a turning point in the 1964 model year. That was the year front-seat lap belts became standard equipment in passenger cars.
Automakers had seen the writing on the wall - or, rather, on the books. Twenty-three states had enacted legislation by 1963 requiring seat belts in front outboard seating positions for all new cars.
'So many states had adopted the requirement, it would have been silly for car companies to make a distinction between the markets that had required seat belts and the ones that had not,' said George Johannessen, a consulting engineer with OmniSafe Inc. in Rochester Hills, Mich.
Factory-installed seat belts transformed seat belt manufacturing. Before 1963, most seat belts were produced in small quantities by about a hundred small producers for aftermarket sales. After 1963, the business was taken over by a handful of well-established suppliers, said Johannessen, who wrote a historical report on seat belts for the SAE in 1984.
The occupant restraint business has evolved into a $4 billion a year industry today, with eight manufacturers of complete restraint systems and about 40 producers of components, reported the Automotive Occupant Restraints Council.
Seat belts were first used in 1885 to prevent ejection from horse-drawn carriages. The restraints were used later on airplanes and race cars.
Automotive safety belts became standard equipment in rear outboard seats in 1967. In 1968, the federal government required seat belts in all forward-facing seats and ordered that shoulder straps be installed in front outboard seats.
SAE estimates seat belts cut the number of crash fatalities 50 percent and reduce serious and severe injuries more than 60 percent. So why did it take so long for the belts to become standard equipment?
First, there were no specifications for making the restraints for many years. SAE introduced some specifications in 1955. Manufacturers of occupant restraints formed the American Seat Belt Council in 1961 to establish uniform production and quality standards.
Some of the systems marketed by small producers were unsafe, said Volvo engineer Nils Bohlin in a taped interview before seat belt standards were introduced. Bohlin invented the one-piece, three-point lap/shoulder belt in 1958. The 1959 Volvo was the first car to be fitted with the three-point lap/shoulder belt as standard equipment.
'Some (early restraint systems) were made out of thin webbing or buckles that were substandard,' said Chuck Pulley, executive director of the Automotive Occupant Restraints Council, originally the American Seat Belt Council.
Second, automakers also assumed that safety doesn't sell cars. Ford Motor Co. promoted safety features including seat belts in the 1956 model year. Chevrolet emphasized styling and performance in advertising during the same year and outsold Ford by 190,000 cars, nearly three times its 1955 margin.
Only government intervention could prod manufacturers to make the belts standard equipment. Without state and federal requirements, there would be little demand for the restraints.
And only state statutes could induce people to use safety belts. Since the mid-1980s, 48 states have enacted laws that require people to buckle up.
Usage was high when seat belts were an option because they were purchased by consumers who wanted to use them. But usage dropped when the restraints became standard equipment.
Laws that mandate buckling up can increase belt use to more than 80 percent, said Johannessen.
Belt use was just 24.7 percent in Michigan before the state adopted a mandatory seat belt law in 1985. But use has now climbed to 66.1 percent, according to the Michigan Office of Highway Safety Planning.
During the past 10 years, Michigan's belt law is credited with saving 650 lives, said the University of Michigan Transportation Research Institute.
The evolution of seat belts has not ended. In fact, the simple belt and clasp have gone high-tech. Cleveland-based TRW Inc., the largest manufacturer of restraint systems, offers a few examples of the changes to expect in auto safety:
Pre-tensioners - small devices attached to the seat belt buckle - can sense a crash and tighten the lap and torso belt to maximize protection.
Pre-tensioners are used in Europe and are expected to debut in the United States in 1998.
'You don't even realize it happens - just bang, and you feel the belt tightening around you,' said Jerry Blevins, TRW vice president of engineering program management.
Load limiters in the buckle are meant to prevent bruises or even broken bones caused by the restraint system in severe collisions. The device gives the belt slack when a vehicle occupant is thrown forward and reaches the maximum force of the belt. Load limiters will appear on 1997 models.
Seat-integrated restraints are seat belts that are built into the seat. That makes the belt more comfortable and easier to use.
'With seat-integrated restraints, no matter what your size or how you have the seat positioned, the seat belt system should always fit comfortably and correctly,' Blevins said. Seat-integrated restraints were introduced in North America during the 1996 model year.
'Smart' restraint systems monitor a vehicle occupant's weight and height, distance from the airbag and crash severity and adjust the seat belt and airbags to boost protection.
Those systems can disable the passenger-side airbag if there is a rear-facing child seat to prevent injury to a child.
Complete smart restraints are expected to debut in the 2000 model year.
Donna Lawrence Harris is an Automotive News staff reporter.
