Did you know that the car seat belt is recognized as one of the eight most significant inventions of the 20th century?
When you travel in a vehicle, buckling up your seat belt is customary. At least, that’s what is expected of everyone traveling in a car, as this feature, available in all motor vehicles, saves lives in case of a collision or rollover. The seat belt is an essential passive safety device in vehicles, designed to keep occupants in their seats during a crash and minimize injuries.
Thanks to seat belt, millions of tragedies have been avoided around the world, ensuring safety inside cars. In 1985, the German Patent and Trade Mark Office chose it as one of the eight most significant inventions of the 20th century. This is why it is seen as the most effective device in history.
According to the World Health Organization, the use of seat belts by front-seat occupants reduces the risk of fatal injuries by 45 to 50%, and the risk of death and serious injuries for rear-seat occupants by 25% (WHO).
However, cars didn’t always have this equipment. Learn here how the seat belt became an indispensable feature in the automotive industry.
Origin and Evolution
The first seat belt was invented in England, but it was in the United States where it received its first patent in 1885. Its design was rudimentary: a simple leather belt that crossed the person’s waist and fastened them to the seat. This same system was already used in horse-drawn carriages, to prevent people from falling off during trips, as a result of the dirt roads on which they moved.
During the 1940s and 1950s, car sales increased, and so did problems on the roads. Due to the numerous crashes and the severity of the often-fatal injuries, in the early 1950s, a doctor named Hunter Shelden began researching the effectiveness of the seat belt. His interest arose because, during his medical practice, he noticed that many of his patients who had been in car accidents, if they hadn’t died, had severe head injuries. This led him to propose the use of a retractable seat belt that allowed some body movement but still secured the driver or passengers safely in their seats, preventing widespread neck and head injuries.
In the 1950s, Preston Tucker was the first automotive company to implement seat belts in cars. However, the initiative didn’t last long as the company went bankrupt shortly after. Then Ford and Nash followed suit and optionally installed seat belts in their cars. Saab was the first brand to include them as standard.
The Invention That Saved Millions of Lives
The first two-point seat belts only secured passengers by the hips, causing people to slide under the belt. Therefore, it was necessary to create a system that secured the entire body and was easy to put on and take off.
Nils Bohlin, who worked for Volvo, came up with the idea of the three-point seat belt. He patented it in 1959. By 1963, all cars made by Volvo incorporated these seat belts, properly securing passengers to prevent them from sliding off the seat and keeping them safe in case of an accident.
Volvo’s design, with three anchor points instead of two, quickly became the universal standard for all street vehicles worldwide. This evolution of the seat belt aimed to meet the need for a belt that secured the upper torso diagonally and the hips while being anchored to one side of the seat without moving.
Since it was an invention meant to protect the entire population, Volvo released the patent for commercialization by different automotive companies. Although many manufacturers resisted implementing it for a few years, they eventually accepted it.
Time and results have confirmed the efficiency and value of Nils Bohlin’s invention. According to data from the Directorate General of Traffic (DGT), the seat belt reduces the chance of death in an accident by about 50 percent. It is estimated that since its creation and adoption by automobiles, this passive safety system has saved millions of lives.
What Are Seat Belts Made of and What Are Their Main Elements?
Polyester is the primary material used due to its high strength and elasticity, although nylon and vinyl are also commonly used to make seat belts and safety ropes. Recently, recycled materials such as plastic bottles and more eco-friendly manufacturing processes have been incorporated into production.
The seat belt consists of three main elements that together have the great ability to save lives: the retractor, which locks the system’s webbing, the buckle, which serves as the anchoring point and is designed to be easily locatable and operable even under tension, and the webbing, which, as we’ve seen, is made from materials that combine high strength and some elasticity.
Innovations and Trends
Seat belt manufacturing has advanced over the years, aiming to improve both efficiency and user comfort. Significant technological advances include the use of pyrotechnic and electric pretensioners that enhance occupant retention in a collision; energy management systems that help distribute impact forces more efficiently; and smart belts that incorporate technologies such as haptic warnings and intelligent load force limitation.
How a Seat Belt Works
In the event of a crash, the seat belt’s pretensioners activate, preventing the passenger from moving out of position and securing them against the seat. These pretensioners are individual and, in the event of an impact, pull the anchoring buckle, preventing the passenger from suffering injuries or hitting the sides or front of the car. Besides the three-point seat belt, the most commonly used system due to its effectiveness, there are other types like the two-point belts, mainly used in airplanes and buses, although their use has been questioned as they keep people in their seats in a road accident but can cause severe injuries, such as lumbar spine separation, which can result in paralysis known as “seat belt syndrome.”
The four-point belt is usually found in harnesses and is similar to the five-point belt but without the crotch strap. The five-point belt is commonly used in child seats and racing cars, providing grip between the legs and over the shoulders. Finally, the X-belt, which is uncommon, adds an additional two-point support belt that crosses to form an “X” with the conventional three-point belt.
Proper Use of the Seat Belt
Here are some recommendations to ensure the proper use of the three-point seat belt:
- The diagonal strap should pass over the shoulder and chest, never under the arm or behind the back. This ensures that the impact force is adequately distributed across the torso.
- The lap belt should fit snugly over the hips and not the abdomen. This helps prevent internal injuries in a collision.
- The belt should be snug but comfortable, not too tight. Ensure the buckle is well-secured and the belt is not twisted.
- Pregnant women should place the lap belt as low as possible over the hips and under the abdomen, with the diagonal strap between the breasts and to the side of the abdomen.
- Children should use appropriate safety seats for their age, weight, and height. Three-point seat belts are not suitable for young children without a safety seat or booster (CRS).
Now you know, when traveling in a vehicle as a driver or passenger, in the front or rear seat, always use the seat belt; it can save your life. We invite you to share this information.
Road safety is everyone’s responsibility.
