Overweight people less safe in a car

Cars have never been as safe as they are today. The number of road deaths and the number of seriously injured car occupants in crashes has been declining steadily for years. Seat belts and airbags play a decisive role in this, but safety experts don’t want to stop there. They continue with research and experiments. Now the German ADAC has identified a hitherto underestimated risk and is sounding the alarm: overweight people, especially tall and older people, are less well protected in cars than average people. In the standardized frontal crash tests, a dummy called the Hybrid III 50e is usually used. This represents a man who is 1.75 m tall and weighs 78 kg. “50th” stands for 50 percent, meaning 50 percent of all men are shorter or taller, heavier or lighter. In short, the standard tests only cover half of the male population. The data on the physical characteristics of the persons dates back to the 1950s. The standard dummy was introduced in the 1990s.

What does that mean for the other 50 percent? What about particularly heavy, light, tall, short and old people? According to the CBS, about half of all adult Dutch people are moderately or seriously overweight and nearly 15 percent of adults are seriously overweight. Accident expert Volker Sandner of the ADAC Technical Center in Landsberg, Germany, investigated the problem target groups on the basis of extensive crash tests. In addition to the standard dummy, the following special dummies were used: tall man (1.91 m, 99 kg), elderly lady (1.61 m, 73 kg), slim woman (1.51 m, 48 kg) and fat man (1 .88m, 125kg). Where a normal dummy costs €200,000, one million euros must be paid for each of the special models. “The older lady is a prototype that we flew over especially,” explains Sandner. It was worth it, he says, because the globally unique crash tests provided valuable insights into the danger to individual groups of people. In a frontal collision at 50 km/h, the most common type of accident in practice, it has been shown that fat people are more injured. For example, the tension in the abdominal area increases from very low to high if a fat dummy is in the car instead of one with a normal posture.

Crash scientist Sandner is even more concerned about the risks to older people. “The analysis of the accident database shows that this group is at extremely high risk,” he says. The reason for this is lower bone density and less muscle mass. Both decrease with increasing age. Serious chest injuries are particularly common in this group. Whether people are fat or old, in both cases advanced security systems can counteract the increased risk of injury. In addition, additional sensors indicate how high the crash speed will be and how heavy, tall and old the person in the car who needs to be protected is. In conjunction with adaptive components such as multi-stage pretensioners or flaps in the front airbags and airbags in the seats, injuries can be reduced to a minimum. “The steering column and knee airbags also offer opportunities for further development,” says Sandner. In the crash test, for example, the acceleration value for the elderly lady was reduced by more than 50 percent, regardless of the seating position, when an adaptive system was used.

Astonishing

The automotive industry should never stand still when it comes to developing new protection systems. It is therefore good that the ADAC focuses on particularly vulnerable occupants of cars. They are often not only (too) fat, but also grow older. Engineers are faced with the challenge of making security systems even better with adaptive solutions. After all, safety is one of the most important selling points. Therefore, it is astonishing that many safety features are disappearing from cars or are not being adopted. For example, the Fiat Stilo from 2005 already had weight sensors in the seats. Or take the Renault Mégane from 2008, which had a seat cushion airbag.

This article originally appeared in the AutoWeek annual special 2022.