Nils Ivar Bohlin was born in Härnösand, Sweden, and received a diploma in mechanical engineering from Härnösand Läroverk in 1939. In 1942, Bohn began working for aircraft manufacturer Saab as a designer, and helped developed ejection seats. In 1958, Bohlin joined Volvo as a safety engineer.
Using skills he acquired developing ejection seats for Saab, Bohlin worked on a prototype three-point seat belt as a means of keeping a driver safe in a car accident. In 1959, he introduced his invention to Volvo, and received U.S. Patent No. 3,043,625. In 1968, Volvo announced that the new seat belt design would be free for the public to use.
The three-point seat belt changed the world by preventing injuries during a car crash. The U.S. National Highway Traffic Safety Administration states that the seat belt has saved about 15,000 lives per year in the United States.
Bohlin demonstrated the effectiveness of the seat belt in a study of 28,000 accidents in Sweden, and determined that unbelted occupants sustained fatal injuries at all observed speeds, whereas no belted occupants were fatally injured at accident speeds below 60 miles per hour or if the passenger compartment remained intact. The study resulted in the U.S. Department of Transportation requiring three-point seat belts in American cars.
In 1969, Bohlin was appointed to lead the Central Research and Development Department for Volvo. In 1974, Bohlin was awarded the Ralph Isbrandt Automotive Safety Engineering Award, and in 1989, he was inducted into the Hall of Fame for Safety and Health. Bohlin received a gold medal from the Royal Swedish Academy of Engineering Sciences in 1995. In 1999, he was inducted into the Automotive Hall of Fame.
Bohlin retired from Volvo as Senior Engineer in 1985. Though he died in 2002 at the age of 82, he was posthumously inducted into the National Inventors Hall of Fame.