Vehicles have to fulfill these safety requirements

The European New Car Assessment Programme (Euro NCAP) is a consumer protection-oriented program to evaluate the safety of passenger cars. It is supported by a consortium of European transport ministries, automobile associations, insurance associations, and research institutes. As of 2020, it has 14 members from various European countries.

These include institutions such as the ADAC, FiA, and GDV, but also ministries such as the German Federal Ministry of Digital and Transport and the Department for Transport in Great Britain. Since 1997, Euro NCAP has become the key valuation benchmark for vehicle safety for both manufacturers and consumers. The results are published and allow car buyers to obtain information quickly and comprehensively on the vehicle safety of an automobile. In addition, the star rating (best: five stars) allows an easy comparison of different vehicles.

The requirements have been continuously developed since their introduction. In the beginning, the focus was still on passive safety—i.e., minimizing the consequences of accidents for occupants and pedestrians—but over time, more and more elements of active safety (accident avoidance measures) have been included in the assessment. In this way, Euro NCAP is following the general trend that new systems that actively protect occupants and pedestrians are becoming increasingly important. Thus, a vehicle is currently evaluated in the following categories:

• Adult occupant protection
• Child safety
• Vulnerable road users (pedestrians and cyclists) and
• Assistance systems.

Vehicle variants with standard safety equipment are generally used for the evaluation. Optional technologies are only additionally tested if it can be assumed that they will be of major relevance in the short term.

Consequently, part of the evaluation continues to focus on passive safety. Various accident scenarios are examined, distinguishing between frontal, side, and rear impacts. These each require different protective measures for the occupants. To ensure safety for occupants of different sizes and weights, six accident situations are currently being tested.

A particularly frequent accident constellation is a frontal collision involving two vehicles. In this case, they usually collide in an offset manner, which places special demands on the vehicles' crumple zone. One side of the vehicle front end alone must be able to reduce the vehicle's speed to a moderate level, and Euro NCAP has been testing this scenario since 1997. In the past, the vehicle was driven against a fixed barrier, but since 2020 a movable barrier has been used. The advantage of this procedure is that conclusions can now also be drawn about "compatibility" with other vehicles.

If a vehicle is considered compatible, then ideally it does not pose any additional risks to the other party involved in the accident. However, if a vehicle has particularly rigid structures and a high mass, it becomes increasingly incompatible, and more of the energy released in an accident has to be absorbed by the other party.

In this test, two so-called 50^th percentile dummies are placed in the front seats. Their physiques represent an average adult male, and they measure a variety of signals such as acceleration, forces, and moments, which are then used to determine the risk of injury. In the rear, the level of protection is determined for two child dummies, corresponding to children aged six and ten sitting in suitable child seats.

To offer a good level of protection for the occupants in the test described, the vehicle should display a certain rigidity in its front structure. However, if this is too stiff, it can lead to increased forces, especially in chest compression, among smaller, lighter occupants. As a result, injuries to the organs can result.

For this reason, a test was introduced on a rigid, non-deformable barrier across the full width of the vehicle. In this test, smaller, lighter occupants, represented by 5^th percentile dummies, are in the driver's and the rear seat. The requirements from the test with the moving barrier and against the rigid wall are thus in some ways opposites, and provide a balanced front structure or occupant protection systems that should enable the greatest possible protection potential for occupants of different statures.

In addition to the requirements for a frontal impact, the lateral collision is also tested. Two different crash tests are currently being used for this purpose. On the one hand, the impact of a movable barrier with a deformation element on the side of the vehicle is simulated. This corresponds to a typical vehicle-vehicle scenario, such as can occur at intersections. Secondly, a lateral pole impact is tested. This corresponds to an impact with a tree, for example, as a result of losing control over the vehicle. Due to the small impact area, this can result in particularly high intrusions into the passenger compartment, which in turn places increased demands on the protection systems. In both tests, a 50^th percentile dummy is placed in the driver's seat. In the barrier test, there are also two child dummies (corresponding to six and ten years of age) in suitable child seats in the rear of the vehicle.

One innovation from 2020 is the consideration of the hazard potential for occupants who are not sitting on the side of impact. For example, if another vehicle crashes into the passenger side at an intersection, the driver will move toward the side of the impact and could then potentially hit the passenger or passenger compartment unprotected. Every vehicle, regardless of whether an additional protection system is installed, is additionally tested for lateral movement of an occupant. If this is moderate and the forces acting on the dummy are also tolerable, the vehicle can achieve the full score even without additional systems. However, if another airbag is installed, e.g., to reduce the forces on the head and neck, an additional 50th percentile dummy is placed on the passenger side in the pole impact test (the barrier test is also still possible for now) to determine the protection potential.

The last scenario to be examined is a rear impact. Even though fatal injuries rarely occur here, whiplash injuries can cause protracted treatment and discomfort for those affected. In addition to a geometric evaluation of the head restraint, two dynamic tests are performed, and the load values are measured on a dummy specially designed for this situation.

In some of the tests described, suitable child seats are tested with the corresponding child dummies. In the various accident scenarios, the respective protection potential is determined and included in the evaluation. In addition, an assessment is made of how well child seats can be installed in the vehicle, aimed at solutions that are as simple as possible and tailored to the consumer. The idea behind this requirement is that all too often children are not correctly secured in child seats, which means that their full protection potential cannot be realized in the event of an accident.

In addition to occupant protection, the risk to vulnerable road users also plays an important role. When evaluating pedestrian protection, two legform impactors are used that can reflect the physical nature and vulnerability of the human leg. One test impactor mainly represents the thigh area, while the other represents the lower leg and the knee. The main focus is on protecting against excessive ligament stretching and bending in the knee area. Manufacturers take this into account especially when designing the front end of new vehicles.

Head impact testing is another requirement for vehicles. Here, too, there are two different test impactors: One represents a child's head in terms of weight and size, the other a typical adult's head. Several measurement points on the hood, A-pillar, and windshield are considered for evaluating head impact. Manufacturers use various design solutions, for example external airbags, deployable hoods, or more free deformation spaces under the hood, to provide the best possible protection for other road users.

In addition, since 2016 there have been requirements to detect an accident in good time and thus avoid it, for example, by emergency braking (active safety). For some scenarios, the use of autonomous emergency steering is also possible. However, the system must not introduce any further danger. The scenarios described here are constantly being further developed and are becoming increasingly complex. For example, various constellations with pedestrians (children and adults) in front of the vehicle are being tested under different lighting conditions and at different relative speeds to each other.

Since 2020, reversing has also been addressed. Here, the vehicle reverses while an adult dummy either moves behind the vehicle or is already standing there, again with the aim of avoiding collision by braking in good time. The turning process has also been investigated since 2020. Here, the vehicle under examination turns at an intersection while a pedestrian crosses the street into which the vehicle is turning. Both right and left turns are examined. Only introduced in 2018, but already expanded in 2020, is the emergency braking system for detecting cyclists. Since its introduction, this has involved two scenarios where the vehicle approaches a cyclist ahead and one where the cyclist crosses the road coming from the nearside. The latter was expanded in 2020: To begin with, a cyclist emerging from behind a parked vehicle must now also be detected, while a cyclist coming from the offside at a slightly greater speed also has to be detected in time.

Similar tests are also carried out with two vehicles. Firstly, collisions with a stationary, a moving, and a braking vehicle at different speeds must be avoided here. Secondly, a turning situation has also been tested since 2020. Here, the vehicle to be tested is turning and in doing so crosses the lane of an oncoming dummy vehicle. Here, too, different relative speeds are investigated.

The lane-keeping assistant is another evaluation criterion. A distinction is made between systems that merely give a warning when the vehicle leaves the lane, those that maintain the lane, and emergency lane assist systems. The latter are tested in very different situations, in some cases also in the absence of lane markings, in the presence of oncoming or overtaking vehicles, and intervene much more noticeably for the driver, since a critical situation has already occurred.

Another important aspect of road safety is speed. To support the driver and prevent him from exceeding a certain speed, speed assistants are evaluated in terms of their function. As with other systems, there is a differentiation here between those that provide information to the driver and/or warn when a previously set speed is exceeded, and those that limit the speed based on the maximum permissible speed.

Other assistance systems target the condition of the occupants. 2020 also saw amendments to the assessment in this respect. In addition to seatbelt reminders for the rear seats (including occupant detection), the driver's drowsiness/attention is also monitored. Such systems operate either using cameras, or indirectly via an analysis of driving behavior.

In the future, the integration of active and passive safety systems in a vehicle will mean that accidents can be increasingly avoided or mitigated. Active braking or steering intervention, for example, can reduce the speed of collisions and thus lessen the severity of accidents. It is therefore logical that Euro NCAP should take these technological developments into greater account.

However, there will still be situations in which accidents cannot be avoided. In these cases, passive safety measures will take effect to provide the best possible protection for the occupants. If serious injuries do occur, time is of the essence. This is why modern vehicles send out an eCall, an automatic message about an accident. In this connection, since 2020 Euro NCAP has been assessing whether the probable number of occupants and the vehicle's last-known position are also transmitted.

At the scene of an accident, the responder teams must be provided with information as quickly as possible to ensure that the occupants are effectively rescued. Since 2020, the assessment of the rescue data sheet has therefore been included in the overall Euro NCAP rating. In addition, various requirements are being examined that are intended to facilitate the rescue of occupants. These include the forces needed to open doors and seatbelt buckles after the accident. The presence of a multi-collision brake also improves the evaluation accordingly.

In 2020, there were several changes to existing tests as well as the introduction of a new side-impact scenario. Significantly higher requirements now need to be met if the maximum rating of five stars is still to be achieved. But even the current ratings will be further tightened in the future to increase safety for the occupants and other road users. In addition, new systems such as V2x communication (i.e., a vehicle's communication with other vehicles or the infrastructure) are to be assessed in the coming years, as this is also seen as having the potential to prevent accidents or mitigate their consequences. The next revision of the requirements is planned for 2023.

Further reading: