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Three-point Safety Belt
Nils Ivar Bohlin, creator of the three-point lap/shoulder
automobile seatbelt, was born in 1920 in Harnosand, Sweden.
In 1939 he completed his B.S. in mechanical engineering at
Harnosand Laroveik. In 1942, he began working for Svenska
Aeroplan Aktiebolaget (Saab Aircraft Company) as an aircraft
designer. There he was in charge of the development of ejection
seats and other pilot rescue systems for supersonic aircraft.
In 1958, Bohlin was hired as a safety engineer for AB Volvo
in Gothenburg, Sweden. In 1959 he became chief of Volvo’s
Automotive Safety Department. Bohlin helped to design and
manage multi-disciplinary accident investigation teams for
cars and trucks. Safety belts were in use at the time, but
the most prevalent design used a single strap with a buckle
over the stomach. This design risked injury to body organs
in high-speed crashes.
Bohlin aimed to find an alternative design that would not
only protect both the upper and lower body, but would also
be comfortable and simple to use. He spent about a year devising
a system that had one strap that would go across the chest
and one that would go across the hips, with a joint for these
two straps located just next to the driver’s hip. The
design held both the upper and lower body in place, and was
simple enough that the driver could buckle up with one hand.
In 1959, Volvo became the first auto maker to introduce Bohlin’s
three-point safety belt design. At first the company put the
belts in cars designated only for its home market, but by
1963 all Volvos came equipped with front seat belts, and the
company decided to make the design free for use by all car
In 1967, Bohlin presented a paper, "A Statistical Analysis
of 28,000 Accidents with Emphasis on Occupant Restraint Value,"
on behalf of Volvo, at the 11th Stapp Car Crash Conference.
The report claimed that the belt had already saved thousands
of lives, reducing the risk of injury or death in car accidents
by as much as 75 percent. This report helped inspire the United
States’ National Highway Safety Bureau to implement
a law requiring automakers to equip the front seats in passenger
cars with three-point lap/shoulder belts. It persuaded a number
of other national governments to do the same.
Since its introduction, the three-point shoulder/lap safety
belt has changed very little in its overall design. Improvements
to the design have included the inertial reel, tensioners
to eliminate slack, force limiters to control the forces needed
to restrain the user, and better buckles. As of today, the
U.S. National Highway Traffic Safety Administration estimates
the belts reduce the risk of deaths in car crashes by at least
In 1969 Bohlin was assigned to the Central Research and Development
Department at Volvo. Later he was named chief research engineer
in the Advanced Engineering Department. He consistently managed
matters related to general automotive safety, including initiating
and managing Volvo’s Traffic Accident Research Group.
Bohlin retired from Volvo in 1985. He earned several patents
during his lifetime related to both aviation and automotive
design and was recognized with numerous awards and honors.
In 1974 Bohlin was awarded The Ralph H. Isbrandt Automotive
Safety Engineering Award. He was honored in 1979 and in 1985
by the National Highway Traffic Safety Administration in Washington,
D.C. In 1995, he received a medal from the Royal Swedish Academy
of Engineering Sciences. In 2002, he was inducted into the
(U.S.) National Inventors Hall of Fame. On the day he was
to be honored for this achievement, Bohlin died at age 82.