A brief history of vehicle safety

10 July 2025

It was in the form of the Benz Patent Motor Car that the automobile first rolled onto the roads of the world in 1888 – ushering in a new era of mobility. But one thing soon became clear: These motorised vehicles with their previously unimaginable speeds also harboured great dangers. As the number of accidents increased, so too did the urgent need to make cars safer. In our brief history of vehicle safety, we tell you how the inventions of the crumple zone, seat belts and assistance systems have all changed the car as we know it.

There’s a black gravestone in a cemetery in the Berlin district of Lichtenberg. On it there is a palm branch, with an engraving underneath: “Here rests in God’s grace our kind-hearted, unforgettable aunt, the property owner Juliane Heumann. Born on 19.07.1839. Departed this life on 13.08.1909. Your noble heart has stopped beating. Good soul, you were killed by a motor car”.

As early as the beginning of the 20th century, car accidents were already a problem and, as we have seen immortalised on a gravestone, a cause of death. How to make these impressive but dangerous machines safer is a question that has taxed authorities and car manufacturers since the early days of the motor vehicle.

When the first cars chattered out of the factory, many roads were still unpaved gravel tracks. There were no traffic rules. Pedestrians, cyclists, horse riders and drivers were all at liberty to find the best and most direct route to wherever they needed to be. In the rain, however, the road was almost invisible to occupants of motor cars. It was for this reason that the American Mary Anderson developed a windscreen wiper, which she patented in 1903. This provided a clearer view during cloudbursts, but still had to be operated manually. A good two decades later, in 1926, Robert Bosch AG presented the world’s first “windscreen wiper with electric drive”.

When it came to vehicle construction, it was still obvious, at least in theory, that strength was the key. Cars were built on a framework made of steel structural members, topped off with solid sheet metal. If a car were to crash into a wall or another vehicle, its body would only be slightly deformed. In doing so, however, it would pass almost all the energy of the impact onto its occupants – with fatal consequences for fragile human bodies.

In 1950, Mercedes engineer Béla Barényi was the first to come to the conclusion that the smart thing was for sheet metal to give way. A controlled and wide-ranging deformation would not render a car any less safe. On the contrary, it would absorb a considerable part of the impact energy, meaning that less of it would reach the occupants. Barényi divided the car body into three boxes: a non-rigid front end, a strong cockpit in the middle for the passengers, and a yielding rear end. In 1952, he was granted the patent for his concept, which went into series production for the first time in 1959 in the Mercedes-Benz W 111 and rose to prominence as the crumple zone.

Barényi's crumple zone became the standard in vehicle construction, making him the father of passive safety: systems and construction methods that mitigate the consequences of an accident. And this gifted designer would go on to render outstanding services to the passive safety cause in another way. He went on to develop components such as reinforced doors to improve side impact protection. Among his more than 2,500 patents was the safety steering column. In the event of a frontal accident, it would collapse rather than penetrating the passenger compartment as a kind of deadly skewer.

Seat belts were still a rarity in the 1950s, being offered only as optional extras for luxury models such as the Mercedes W 111. Lap belts, such as those used in aircraft, were the most commonly used form. These would prevent the occupants from being catapulted forward through the vehicle in the event of an accident. But they would not stop torsos and heads from crashing into the dashboard or windscreen. “Moreover, in the event of an accident, a lot of energy is directed into the pelvic and abdominal area, which can result in further serious injuries,” explains Leif-Erik Schulte, Head of the Institute of Vehicle Technology and Mobility (IFM) at TÜV NORD.

Volvo engineer Nils Ivar Bohlin was working on a remedy. On 29 August 1958, he received the patent for his belt system, which combined a lap belt with a shoulder belt and thus “[restrained] both the upper and the lower body in a physiologically favourable way and [was] easy to attach and disconnect.” The following year, his three-point belt (so called because it is connected to the body at three points) was used for the first time as standard on the Volvo 544. “When it came to safety, the three-point belt was a huge leap forward,” says Mr. Schulte. But it was not until 1974 that new cars in West Germany were required by law to be equipped with front seat belts.

From 1976 onwards, belting up in the front became mandatory, but persistent offenders did not yet have to live in fear of being fined. Educational campaigns such as “Clunk-click with every trip” only helped to a limited extent against the widespread aversion to seat belts: Their usage rate would increase by just 19 percent in the following years. More than one in three would still take to the road without belting up. It was not until 1984, when a fine of 40 marks was first imposed for not wearing a seat belt, that the rate jumped from 60 to 90 percent within just a few months. With immediate consequences: The number of traffic fatalities fell from 10,199 to 8,400 between 1984 and 1985, and the number of serious injuries decreased by around 15,000. “If you want to change ingrained driving habits, you always need to apply pressure from the outside," says Mr. Schulte. Today, the seat belt has long been considered the most important driving lifesaver, and the German Patent and Trademark Office considers it to be one of the inventions that have brought the greatest benefit to humankind in the last 100 years.

Of course, even the best seat belt cannot absorb everything. Munich-based engineer Walter Linderer applied for a patent for an airbag system way back in 1951. For context, this was the same year in which motor vehicles in the Federal Republic of Germany first had to prove their roadworthiness in the periodic inspection. However, Linderer’s airbag, which was powered by compressed air, did not yet pass the practical test: Because of the inadequacy of the existing sensor technology, it could not reliably detect accidents and would inflate too slowly. It was not until 1968 that the first modern airbag, ignited by pyrotechnics, was introduced.

In Germany, Mercedes first offered a driver’s airbag as an optional extra for its S-Class in 1981. Volvo launched its first side airbag in 1994, followed in 1996 by Kia with the first knee airbag. Two years later, in 1998, a safety system that was incomparably simpler in technical terms but nonetheless highly efficient finally became mandatory in Germany: the head restraint, which significantly reduced the risk of whiplash injuries and damage to the cervical spine.

As cars became safer for their occupants, attempts were also made over the course of many years to protect pedestrians, primarily by means of new regulations and adaptations of the traffic infrastructure. These included zebra crossings, raised kerbs, pedestrian-controlled traffic lights and the establishment of traffic-calmed zones.

In 1997, Euro NCAP – an organisation of European transport ministries, insurance companies and automobile clubs – published crash test results for the first time and assessed how well vehicles would protect pedestrians in the event of an accident. How many stars a vehicle model had been awarded by NCAP would become an increasingly important factor in purchase decisions. In 2005, the EU made manufacturers responsible for pedestrian protection for the first time. From then on, they would have to prove in crash tests that they would not exceed defined limit values for collisions with pedestrians.

Car manufacturers began to design the front ends of their vehicles to be more “pedestrian-friendly”: Sharp edges were eliminated, bonnets made rounder and engines installed deeper beneath the bonnet to absorb any impact. Some car manufacturers also turned to bonnets that would automatically spring open in the event of a frontal collision to reduce the risk of serious head and chest injuries.

And such passive measures can indeed significantly mitigate an impact, as was the finding of a 2013 study carried out by accident researchers on behalf of the insurance industry. The study concluded that they were not sufficient on their own, however. What would be much more effective would be to actively reduce the impact speed by installing emergency brake assistants.

But despite all the progress, we are still a long way from Vision Zero, i.e. zero deaths in traffic. Mr. Schulte is convinced that further technical developments could play their part in achieving this goal. “If vehicles can communicate reliably with the infrastructure and each other in the future and be warned in advance of dangerous situations, this will be another big step towards avoiding accidents.”