Keywords

Introduction

Over the last decades, the improvement of vehicle safety has emerged as one of the most cost-effective and leading strategies to reduce road casualties. Vehicle safety technology accommodates everyday human mistakes: by actively encouraging the driver to adopt safe driving habits; by maintaining control of the vehicle in critical situations; and, in the event of a crash, by reducing injury to occupants and the consequences of those injuries. According to the European Road Safety Observatory report on Vehicle Safety (2018), safety technology “… is fundamental to a Safe System approach which requires safe interaction between users, vehicles, the road environment and prompt access to the emergency medical system. Vehicle design, which takes account of the behavioural and physical limitations of road users and other system risks, can address a range of risk factors and help to reduce accident involvement, accident injury severity and accident injury consequences” (Fig. 1).

Fig. 1
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Vehicle design contributes to the safety system approach by helping to reduce accident involvement, accident injury severity, and accident injury

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By now, safety systems have demonstrated their effectiveness in substantially mitigating injuries from crashes (Broughton 2003) and in preventing crashes. What makes the promotion of safer cars such a compelling proposition for society is that, year in, year out, new safety-enhanced vehicles are coming to the market, substituting older, less safe vehicles on our roads. As best practice activity, and following the recommendations of the Decade of Action’s Global Plan for Road Safety 2011–2020 (World Health Organization 2001), many countries have successfully stimulated improvements in vehicle safety, mandating the use of safety systems like seatbelts and child restraints, and actively encouraging the uptake of new technologies.

Ever since the car became the most popular mode of transport in more developed countries, safety has been a top concern for car buyers and fleet operators. In many nations, regulations have been put in place to establish minimum levels of vehicle safety. Furthermore, consumer information regarding automotive safety has educated the public about safe vehicle design and the differences that exist between specific makes and models and thus influenced the level of safety provided by vehicle manufacturers. Therefore, consumer demand for safer cars has become a catalyst to car manufacturers and governments to improve vehicle safety standards throughout the world.

In 1979, the National Highway Traffic Safety Administration (NHTSA) launched the first New Car Assessment Program (US NCAP) to provide information to consumers on the relative crashworthiness of automobiles (Hershman 2001). The outcome, the first public prospective safety ratings for cars, mobilized consumers and allowed them to make better-informed buying decisions. This in turn incentivized local vehicle manufacturers to innovate and provide safer vehicles at lower prices to attract more customers (Fig. 2).

Fig. 2
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US NCAP safety rating information published by NHTSA is required to be part of the Monroney (automobile price sticker) label

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The success of NHTSA’s first safety ratings has since inspired other regions and organizations to develop their own consumer safety rating programs based on the same principle. Over the last 25 years, several official programs have emerged around the world, covering high-income markets such as Japan (Wani et al. 2001), the Republic of Korea (Korea Ministry of Land, Infrastructure and Transport 2014), Australia and New Zealand (Haley and Case 2001), Europe (Hobbs and McDonough 1998), and upper and lower middle-income markets like China, Latin America (Furas and Sandner 2013), and South-East Asia (Anwar Abu Kassim et al. 2013). The insurance industry has also launched its own safety ratings, with the Insurance Institute for Highway Safety (IIHS) (1995) in the USA as its main proponent. More recently, Global NCAP (2015) has introduced the concept to emerging markets, such as India and South Africa, calling for minimum vehicle safety standards across the regions and holding the industry accountable for not adhering to the same ethics everywhere. The level of engagement worldwide and the NCAP activity that is still visible today underlines the importance of consumer vehicle safety ratings to many regional road safety policies and demonstrates that the NCAP approach can be successfully applied to countries with very diverse market conditions and vehicle fleets.

The European New Car Assessment Program (Euro NCAP) was established in 1997 with the aim of providing motoring consumers with a realistic and objective assessment of the safety performance of the most popular cars sold in the European Union (Fig. 3).

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Euro NCAP’s first launch included safety ratings for seven popular supermini’s and raised major concerns about their crashworthiness

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Euro NCAP is a public-private partnership which operates independently from the European type approval system. At present, the organization has 12 members including the member state governments of the United Kingdom, Germany, France, Sweden, the Netherlands, Luxemburg, and the regional government of Catalonia; the International Automobile Federation FIA; motoring clubs ADAC and ACI; Consumers International; and Thatcham Research, primarily focused on the needs of the motor insurance industry (Van Ratingen et al. 2016). Among all NCAPs, Euro NCAP is considered one of the more established programs and its test and assessment protocols are often referenced by newer programs. The European Commission believes that Euro NCAP has become the single most important mechanism for achieving advances in vehicle safety in the European market (European Road Safety Observatory 2018).

Consumer Safety Ratings as Policy Mechanism

Fortunately, today’s modern cars offer more occupant protection and accident avoidance technologies than a typical model from a decade ago. Still, not all cars are equal; clearly some models are better equipped and may perform better in real life than others. The principle behind consumer testing is to reveal the “hidden” differences between cars, so that the potential buyer can take this knowledge into account when purchasing a new car.

Consumer ratings involve comprehensive, objective, and realistic comparative testing of cars and components which have been proven to be important in crashes, applying best-practice, consumer-oriented criteria and thresholds that allow discrimination between models. The results are shared with the public in an easy-to-understand way, often using “stars” to classify levels of performance. In order to stay relevant to the public, NCAPs must evolve over time and focus on new areas of safety and new life-saving technologies entering the market.

Consumer rating programs are essentially a form of “self-regulation.” It is important to note that the power of consumer testing comes from its accessibility to non-experts, in its use of open and transparent test methods and simple presentation of results, allowing easy comparison of vehicles’ performance. This active dissemination of their findings – online, on social media, in printed magazines, etc. – distinguishes NCAPs from legislative compliance testing, where tests are conducted in secret and results remain undisclosed to the general public. The influence of rating programs comes from their ability to provide the public with an enhanced understanding of the car’s performance and bring a competitive advantage to those that perform best in safety testing. Ultimately, the availability and value of vehicle safety in society is determined by a combination of international and national regulation, consumer information, car industry policies, and product liability considerations .

The Development of NCAP

The roots of many consumer rating programs can be found in regional vehicle crash test legislation. This means that a compliance crash test has been adopted but altered in order to motivate manufacturers to optimize safety performance beyond the minimum legal requirements. To this extent, most NCAP programs have begun crashworthiness testing in frontal impact conditions using Hybrid-III adult crash test dummies (Backaitis 1994) to assess the injury risk.

As vehicles became increasingly better in frontal crash protection, new opportunities for improving safety further were considered. The different objectives, markets, and priorities of various consumer rating programs led to a smorgasbord of new tests that have found their way into consumer rating programs over the last decades. The following will provide you with an overview of the most popular rating tests.

Vehicle Frontal Crashworthiness

US NCAP’s first full-width front barrier test was derived from Federal Motor Vehicle Safety Standard (FMVSS) No. 208 but executed at higher severity compared to the compliance test, in order to raise intrusion and acceleration levels in the occupant compartment (Hershman 2001). Similarly, IIHS, Australasia NCAP, Euro NCAP, and others adopted the moderate offset deformable barrier test (UN/ECE 1995) at a higher impact speed than regulation, alone or in addition to the full-width test. In most instances, the biomechanical injury criteria (HIC, chest accelerations, etc.) are not unlike those applied for regulation testing, but more demanding limits or additional requirements are often set. As a result, a car which barely meets legal requirements is likely to be limited to a one- or zero-star rating by NCAP.

The above approach of basing consumer ratings on compliance testing has allowed standards in occupant protection to evolve at a fast pace. In Europe, the start of Euro NCAP testing coincided with the full implementation date of directives for frontal and side vehicle impact (96/79/EC and 96/27/EC, respectively). From 1997 onwards, new batches of test results were launched about twice each year, sometimes during public car exhibition events (Fig. 4).

Fig. 4
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Between 2000 and 2005, Euro NCAP exhibited crashed cars at public squares across several cities in Europe to raise awareness about vehicle safety among consumers

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Soon car manufacturers, setting aside their initial reservations, started to sponsor the testing of their own cars. As new car models replaced those already tested, the improvements in occupant protection over and beyond the legal requirements, such as reinforced cabin structurers, driver and passenger airbags, and seat belt load limiters and seat belt retractors, could be clearly observed (Hobbs and McDonough 1998). Following the success of the first five-star rating for the Renault Laguna in 2001, manufacturers increasingly saw this as the goal for all their new models for the European market.

However, success does not always come easy. Latin America is one of the world’s worst performing regions with an annual road fatality rate of 17 deaths per 100,000 individuals, almost double the average rate registered for high-income countries (World Health Organization 2013). When Latin NCAP was first launched in South America in 2010, many models failed to meet the frontal impact test requirements, despite being produced by manufacturers who were routinely achieving five-star ratings in Europe and elsewhere. Cars which were ostensibly the same, often carrying the same name, were made to very different standards and were very differently equipped, in different parts of the world. Since then, visible progress has been made yet zero-star results are no exception. The program is still searching for the broad industry engagement that is needed to improve vehicle safety as the governments responsible have so far been unable to agree on realistic minimum safety requirements for the region. This reminds us of an important lesson: that consumer information works best when complementing regulation but cannot, and should not, replace it.

Since the early 1980s, improvements in frontal crashworthiness claim to have reduced the risk of death and serious injury for car occupants by half or more. For instance, IIHS reported a 46% lower risk in death and injury in head on crashes for good versus poor rated cars (HLDI 2019). Frampton et al. (2002) analyzed real-world collisions and medical records from injured drivers and identified significant reductions for serious and fatal injuries in new cars in frontal impacts. They attributed the observed improvement in injury levels to improvements in crashworthiness and the introduction of vehicles with airbags and more effective restraints. Comparing the fatality risk for car passenger in collisions with other cars, Folksam (Kullgren 2017) estimated that cars introduced in the period 1996–2004 had a 43% less risk than those launched in period 1985–1995. This risk has further reduced to 86% for the latest generation of cars, introduced between 2005 and 2014.

Even after many years of testing, the full-width and moderate offset frontal crash tests speak to the imagination of consumers and for this reason remain important tests for many NCAPs today. Despite this, frontal impacts are still the most common type of crash resulting in fatalities and this has driven an obvious interest in further improving frontal crash protection among NCAPs. Small overlap frontal crashes primarily affect a vehicle’s outer edges, which are not well protected by the traditional crush-zone structures. The IIHS small overlap (SO) frontal crash test (Sherwood et al. 2013) is primarily a test that drives structural countermeasures although it may also be a challenge for some belt restraint and airbag designs because of the higher oblique loading component. Vehicle manufactures have responded by strengthening the occupant compartment, adding new structures to engage the barrier and creating an additional load path for crash forces (Fig. 5).

Fig. 5
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Areas modified for small overlap performance. Not pictured: door beam, seat mount, wheel, steering column. From: Insurance Institute for Highway Safety. Status Report, Vol. 49, No. 11

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Other notable upgrade to frontal crash testing is the adoption of the advanced Test Device for Human Occupant Restraint THOR-M mid-sized male crash test dummy (Ridella and Parent 2011; Parent et al. 2013) and biomechanical injury criteria in two new test procedures: the moving deformable barrier (OMDB) test procedure for evaluating small overlap and oblique crashes (Saunders et al. 2011), announced by NHTSA (National Highway Traffic Safety Administration 2015) and Euro NCAP’s mobile progressive deformable barrier (MPDB) test for vehicle compatibility evaluation introduced in 2020 (Sandner and Ratzek 2015; Sandner et al. 2019).

Encouraging Side Impact Protection

In most developed markets, side crashes account for about a quarter of passenger vehicle occupant fatalities and a more sizeable 40% of serious injury crashes. In the mid-1990s, vehicle makers started to install side airbags and strengthen the structures of vehicles to prevent ejection and provide a survivable occupant environment. Around the same time, moving deformable barrier and side pole crash tests were introduced in consumer rating programs to verify the effectiveness of these measures, to drive market installation rates, and promote further innovation.

NHTSA began testing passenger cars in side impact in NCAP in 1997 (Hershman 2001). The US NCAP side impact – a 90-degree side impact in which a moving deformable barrier, crabbed at 27 degrees, strikes a stationary vehicle - is taken from FMVSS No. 214 but run at approximately 62 km/h, 8 km/h higher speed than in the compliance test. In Europe, Australia, and Asia, side impact barrier tests are also performed but follow the perpendicular (non-crabbed) test configuration of the UN/ECE standard (UN/ECE 1995) at speeds ranging from 50 to 55 km/h. However, as head impact does not regularly occur in the barrier test, some have adopted an additional pole test to assess the benefit of head protecting airbags for side impact. In the USA, IIHS was concerned that these tests still did not completely capture the types of crashes likely to occur in the real world with SUVs and pickups. In 2003 the Institute initiated its own test with a different barrier – one with the height and shape of the front end of a typical SUV – and a new small female dummy, SID-IIs (Insurance Institute for Highway Safety 2017).

Since then, the various tests underpinning the side impact crash ratings around the world have continued to evolve. More recent developments include the application of an oblique pole test by US NCAP and Euro NCAP, among others; the adoption of the advanced WorldSID mid-sized male dummy (Scherer and Cesari 2001); the Advanced European Mobile Deformable Barrier (AE-MDB) (Ellway et al. 2013); an assessment of the head protection device extended to rear seats by JNCAP and Euro NCAP, and the application of far-side impact testing (Ellway et al. 2019).

The focus on improving side impact protection has delivered real benefits. IIHS estimated that the overall effectiveness of side impact protection measures, particularly side airbags and curtains, was a 45% fatality reduction for drivers of cars with head-protecting side airbags, and 11% reduction with torso-only side airbags (Insurance Institute for Highway Safety 2003). NHTSA showed statistically significant fatality reductions between 8% and 31% for four types of curtain and side airbags in near-side impacts for drivers and right-front passengers of cars and LTV (National Highway Traffic Safety Administration 2014). Folksam and Chalmers also reported a significant reduction in the injury risk in side impact for near-side occupants based on an analysis of STRADA (Swedish Traffic Accident Data Acquisition) data (Stigson and Kullgren 2011).

Forgiving Vehicle Front-End Designs for Pedestrians and Cyclists

According to the World Health Organization, over a third of road traffic deaths in low- and middle-income countries are among vulnerable road users (World Health Organization 2013). In high-income countries, pedestrian motor vehicle crash fatalities have decreased over the last decades but still account for 15–20% of crash deaths. The pedestrian protection subsystem tests, developed and validated by the European Enhanced Vehicle safety Committee (EEVC 2003), have been the basis for testing and assessment protocols by Euro NCAP, Australasian NCAP, Japan NCAP, as well as UN regulation. These tests, which evaluate the aggressiveness of vehicle front-ends in car-to-pedestrian impacts, comprise the legform to hood test, the upper legform to bonnet leading edge test, and the headform to bonnet top test, each with its own impactor, impact conditions, and criteria.

Car front-end structures initially improved only gradually as the vehicle industry resisted expensive engineering solutions and requirements that could compromise vehicle styling. The test method was also criticized for a lack of reproducibility, resulting from test point selection and poor test tool repeatability. In 2009, Euro NCAP addressed the lack of progress by introducing a new rating system that required minimum performance in pedestrian testing in order to achieve an acceptable star rating. It also solved the main concerns about the test procedures by various updates (Zander et al. 2015) and the adoption of improved impactor devices, such as ACEA head forms and the JARI Flex Pedestrian Leg Impactor (Konosu and Tanahashi 2005). The proportion of vehicles offering good pedestrian protection has since noticeably improved.

The inclusion of pedestrian subsystem testing in consumer ratings has brought about more pedestrian-friendly designs and has triggered new innovations such as “pop-up” or deployable bonnet technology. In the latter case, an extension to the subsystem test procedure was needed to evaluate the robustness and effectiveness of the deployable device itself. The method features sensor activation tests carried out with a special PDI2 legform (Concept® Technologie 2015) to check system responsiveness to pedestrians of various sizes, and numerical simulations using “certified” human models (Klug et al. 2017) to verify that deployment occurs before the head contacts the bonnet. This experimental-numerical method is the first of its kind in consumer testing.

A significant correlation between pedestrian subsystem scores and injury outcome was reported by Pastor using German National Accident Records from 2009 to 2011 (Pastor 2013). Comparing a vehicle scoring 5 points and a vehicle scoring 22 points, pedestrians’ conditional probability of getting fatally injured was reduced by 35% (from 0.58% to 0.37%) for the latter. Strandroth et al. (2013) also showed a significant reduction of injury severity for cars with better pedestrian scoring. The reduction of Risk of Serious Consequences (RSC) for medium-performing cars in comparison with low-performing cars was 17, 26, and 38% for 1, 5, and 10% of medical impairment, respectively. These results applied only to urban areas with speed limits up to 50 km/h, suggesting that in order to reduce injuries at higher impact speeds, other types of countermeasures should be considered .

Mitigating Rollover and Loss of Control Crashes

The 1990s and early-2000s saw the sales of Sport Utility Vehicles (SUV) and pickup trucks surge in the North America and Australia. These vehicles, with high centers of gravity, have an inherently greater risk of rolling over and, with such crashes causing some 10,000 fatalities annually in the USA by the start of the new millennium, it was not long before this accident type became a key priority. In 2001, NHTSA added a new test for rollover resistance assessment to their rating system using a “Static Stability Factor” (SSF), based on a vehicle’s measured static properties. The US NCAP rollover resistance rating was later amended to include the results of a dynamic vehicle test in addition to the SSF (Hershman 2001). In 2009, the IIHS began testing the roof strength of vehicles, to ensure that the roof can maintain the occupant survival space when it hits the ground during a rollover (Insurance Institute for Highway Safety 2012). Today, consumer information on rollover resistance remains largely a North American phenomenon. A notable exception is Korean NCAP which adopted the dynamic rollover assessment in 2004 and since published a Driving Stability Rating based on rollover and braking tests (Korea Ministry of Land, Infrastructure and Transport 2014).

Another effective countermeasure to avoid the cause of many rollovers, especially fatal single-vehicle ones, is Electronic Stability Control (ESC), an electronic system that improves a vehicle’s stability by detecting and reducing loss of traction. When ESC detects loss of steering control, it automatically applies the brakes to help “steer” the vehicle where the driver intends to go. ESC, or Electronic Stability Program (ESP) as it was better known at the time, made its breakthrough after the “flip over” crisis of the Mercedes-Benz A-Class in 1997, that generated widespread consumer interest. In the years that followed, several studies confirmed that ESC is highly effective in reducing single-vehicle crashes (Lie et al. 2004; Thomas 2006; Farmer 2010) bringing the anti-skid technology further into the focus. Installation of ESC equipment was successfully promoted by the international Choose ESC! campaign (Fig. 6), supported by the FIA Foundation, the European Commission, and others (2007). The technology was adopted in several rating programs, such as Australasian NCAP, US NCAP, and Euro NCAP, before it became mandatory for all passenger cars and light trucks in their respective markets. ESC remains an important condition for five stars in Latin and ASEAN NCAP and for other emerging markets, where this technology is still not mandated.

Fig. 6
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Left: The Choose ESC! campaign organized test drives and demonstration events around to world to promote ESC. Right: Euro NCAP added an ESC test in 2011

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Promoting Seat Belt Usage

As protection for belt wearers improved, accident data increasingly showed that a higher proportion of seriously and fatally injured casualties were not wearing their seat belts (Frampton et al. 2006). To improve this situation, Euro NCAP (2003) first developed a protocol to encourage the fitment of Intelligent Seat Belt Reminders (SBR) . Research had shown that most non-wearers could be persuaded to use their seat belt if they were given a suitable reminder. Although simple reminders have been available for many years, intelligent systems can be much more effective: almost unnoticed by belt wearers but increasingly aggressive and demanding for those who do not “buckle up.”

For front seats, Euro NCAP requires a “final (reminder) signal,” which must be audio-visual and must be presented at the latest 60 s after the engine start, after 500 m of vehicle travel or speeds above 25 km/h. The final signal must last for a minimum of 90 s and consist of a “loud and clear” audible signal and a visual indicator. For rear seats, Euro NCAP requires a “start signal,” which may be visual only. For all seats, if a change in belt status occurs at speeds above 25 km/h, i.e., a belt gets unbuckled, an immediate audible signal must be given. The Euro NCAP protocol recommends occupant detection on the rear seats but does not require it.

Since 2003, Euro NCAP and Australasian NCAP rating systems have encouraged front and rear SBR by awarding points that count towards the overall score or, more recently, the Safety Assist component of the rating system. Thanks to this incentive, most light vehicles in these regions offered SBR for all seats ahead of regulation. From September 2019, UN/ECE regulation UN R16.07 requires seatbelt reminder systems in all front and rear seats on new cars.

When Japan NCAP introduced an overall rating scheme in 2011, SBR points became part of the evaluation. It also includes a reward for advanced seat belt reminders on the rear seats: additional points can be scored if the rear SBR alert includes an audible warning of at least 30 s. Such a warning, however, can only be triggered if passenger presence information is available (Mousel et al. 2015). Several other NCAPs, such as Korean, China, ASEAN, and Latin NCAP have included incentives for the SBR systems into their rating. From September 2019, the United Nations Economic Commission for Europe (UN ECE) Regulation No. 16 on safety belts and restraint systems requires mandatory fitment of safety belt reminder systems to the driver’s seat and to any other seating positions in the same row as the driver’s seat for all M and N category vehicles.

Lie et al. (2008) conducted an extensive study into the effect of enhanced SBR in six European countries. This study concludes that seat belt reminders fulfilling Euro NCAP’s SBR protocol significantly increase seat belt use in daily traffic: around 80% of drivers who do not wear a seat belt in cars with no reminder do so in cars equipped with a system that has a visual signal and an associated loud and clear sound signal .

Safe Transport of Children

Many high- and middle-income countries require the use of approved child restraint systems (CRS) for infants and children, meeting specific criteria for certain age or size groups, even though the exact requirements in each country, region, or state may vary considerably. Especially in developed nations, child fatalities in motor vehicle crashes have steadily declined over the last decades, thanks to these laws and greater consumer awareness. However, vehicle crashes remain a leading cause of death and disability for children and young adults in many parts of the world today.

Safe transport of children in cars is the joint responsibility of parents, child restraint suppliers, and vehicle manufacturers. Responsible parents and caregivers must ensure that children are properly restrained in a correctly installed child restraint system that is appropriate for the size and weight of the child. Child restraint suppliers make certain their products meet (or go beyond) local regulations, offer adequate protection, and can be fitted easily and correctly in all cars. Finally, it is the vehicle manufacturers’ obligation to guarantee that children are as well protected as adults in the event of crash and that special any provisions needed for children are offered as standard.

In practice, this joint responsibility leads to a set of complex interactions and a patchwork of solutions that make it difficult for average consumers to know how their child is carried in the best and most safe way. There exist several child seat consumer rating programs worldwide aiming to guide consumers into buying the best seat for their child. Organizations such as Consumer Reports in the USA (2019), China Automotive Technology Research Centre (2019) and collaborative programs, like the European Testing Consortium (Van Ratingen et al. 2019) (Fig. 7), Australian Child Restraint Evaluation Program (Suratno et al. 2007), and the Latin American Child Restraint Systems Evaluation Programme PESRI (2017), are regularly testing new child restraints for crash performance, ease of use, and how they fit into vehicles. These benchmarking tests have become powerful means to drive improvements in CRS design, as a good consumer rating is a must for child seat manufacturers to be successful in the market.

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Side impact test setup used a.o. by the European Testing Consortium to evaluate the protection offered by Child Restraint Systems

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There are also many aspects of child protection which cannot be influenced by the child restraint manufacturer alone, but which require action on the part of the car manufacturer as well. In 2003, Euro NCAP introduced a child occupant star rating, specifically addressing the vehicle design and equipment for safe transport of children. The rating was based on the protection offered in the front and side crash tests to a 3-year-old and 18-month-old child seated on the rear seat in a restraint of the type recommended by the car manufacturer. The assessment was complemented with other incentives with regards to communication (handbook instructions, information at dealerships, warning labels, etc.), an assessment of the ease of child seat installation, and availability of easy-to-use ISOFIX attachments and other relevant equipment, such as a front passenger airbag deactivation switch. Between 2013 and 2016, Euro NCAP introduced several updates to the child occupant assessment rating including a Child Restraint System Installation check, new incentives for iSize compliant seating positions, and the use of Q6 and Q10 child dummies in crash tests (Van Ratingen et al. 2019).

Among all NCAP programs, a similar assessment of child safety, based on different child dummies seated in child restraint systems in the rear, has been adopted by Australasian NCAP, ASEAN, and Latin NCAP. China NCAP introduced child safety assessment in full frontal 50 km/h rigid barrier test from 2010 (Hu et al. 2011). For the China NCAP 50 km/h full-width test, a P3 child dummy is positioned in the vehicle outboard rear seat, but in the opposite side, a Hybrid III small female dummy is positioned. The IIHS does not use child dummies in their front and side crash testing – a small adult female dummy, comparable in size to a 10-year-old child, is placed on the rear seat for the side impact test – but its LATCH ease-of-use ratings (Insurance Institute for Highway Safety 2015) are an indicator of how easy it is to achieve a correct, tight installation of a child restraint in a given vehicle when using the dedicated child restraint attachment hardware.

The use of child safety seats and improved car measures have been shown to reduce infant deaths in cars by approximately 71% and deaths to small children by 54% (National Highway Traffic Safety Administration 2002). Especially rearward-facing systems have demonstrated to reduce injuries between 90% and 95%, while forward-facing systems have been shown to have an injury reducing effect of approximately 60% (Tingvall 1987). Therefore, in countries where the usage rate is low, are to increase the use of child restraint systems and to provide adequate information about how they are correctly used in the vehicle in order to avoid misuse .

Whiplash Prevention

Whiplash-associated disorder remains the most frequently reported injury in insurance claims across many high-income countries. As whiplash injury to the neck often leads to long-term impairment, with 10% of people suffering long-term discomfort and 1% permanent disability, addressing “whiplash” neck injuries, understanding the cause and how to prevent the injury has been an important priority for the auto insurance industry and governmental bodies.

Whiplash may occur in all impact directions, but the injury is most frequently observed, and its risk most effectively addressed, in rear-end impacts. For this injury type, no biomechanically based vehicle safety regulations exist, mainly because of the limited (or inconclusive) knowledge available about the exact injury mechanism. However, research has demonstrated that, in the event of a rear-end collision, the vehicle seat and head restraint are the principal means of reducing neck injury (Farmer et al. 2003).

Starting from the assumption that lowering loads on the neck lessens the likelihood of whiplash injury, the first stand-alone consumer tests for seats and head restraints were developed by Folksam and the Swedish Road Administration (SRA) (Krafft et al. 2004) and the International Insurance Whiplash Prevention Group (IIWPG) of the Research Council for Automobile Repairs (RCAR 2006). Both initiatives used car seats mounted on a sled to evaluate and rate the ability of seats and head restraints to prevent neck injury in moderate- and low-speed rear-end crashes. Measurements were taken from the BioRID II dummy, an anthropomorphic test device with a flexible spine (Davidsson et al. 1998), which, in the case of IIWPG, were combined with an evaluation of the head restraint geometry. However, the tests adopted different philosophies with regards to relevant seat performance parameters, one putting heavy emphasis on real-world validation (IIWPG), the other using plausible hypotheses regarding the causes of whiplash injury (SRA).

IIHS has been publishing ratings of head restraint geometry since 1995 and has been rating head restraint systems since 2004 using a combination of their static measurement procedure and the IIWPG developed “single-pulse” dynamic sled test procedure. Between 2003 and 2008, the German Automobile club also published whiplash ratings. The ADAC test procedure was similar to the IIWPG test procedure but with an additional sled test and seat stability test (Lorenz and Sferco 2004). Australasian NCAP began publishing head restraint geometry ratings to the IIWPG protocol in 1997 and added the dynamic test in 2012. Also, Korean NCAP and China NCAP adopted a dynamic test based on the IIPWG pulse during the late 2000s (Fig. 8).

Fig. 8
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Typical whiplash seat sled test setup with the BioRID-II dummy, used by many NCAPs around the world including IIHS, Euro NCAP, JNCAP, and China NCAP

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In 2008, Euro NCAP launched its first series of results of (front) seat testing based on its own geometric and “three pulses” dynamic sled test procedure, which combined aspects of the IIWPG, Folksam/SRA, and ADAC methods (Van Ratingen et al. 2009). In 2014, the Euro NCAP’s geometric assessment procedure was extended to include rear seats. Japan NCAP has conducted similar assessments of seats in Japan using different injury criteria and pulses starting from 2010 onwards (JNCAP 2014).

Kullgren et al. (2015) carried out an evaluation of the effectiveness of Euro NCAP, Japan NCAP, and IIHS whiplash protocols, respectively, using real-world crash data. Three analyses were undertaken comprising an analysis of test outcome data, a logistic regression analysis, a receiver operating characteristic (ROC) analysis, and a correlation analysis comparing crash and injury outcome. Correlations between the test scenarios of each of the three protocols – as well as the outcome associations with crash outcomes – suggested consistent improvements in the risk of permanent medical impairment. Encouraged by the positive impact of whiplash seat testing around the world, amendments to Global Technical Regulation on Head Restraints No. 7 to address minor whiplash injuries were finally agreed in 2019 .

The Advent of Crash Avoidance

By the mid-2000s, crashworthiness ratings had been in common use around the world for a decade or more and the industry’s efforts to deliver increasingly safer cars had resulted in many five stars successes. But while this represented a significant step forwards for consumer protection, concerns started to rise over the future direction and the message that the programs continued to deliver.

The key reason behind these concerns was the emergence on the market of a new category of safety technologies designed to automatically intervene in critical, near-crash situations and assist the driver in driving safely, the so-called Advanced Driver Assistance Systems (ADAS). Several car manufacturers have made their commitment to active safety clear, among them Daimler, but also Volvo, which was among the first to offer a collision mitigation system as a standard installation in a consumer vehicle. Yet, crash avoidance and ADAS technology was largely overlooked by consumer rating programs at this time (with the notable exception of Electronic Stability Control, which was encouraged by several NCAPs in the late 2000s).

The industry’s shift from passive to active safety initially put the NCAPs on the backfoot as they grappled with the wide variety of new systems and functionalities entering the market and the lack of suitable, “regulation-quality” performance tests for these new systems. To make matters worse, only a few systems were offered as standard and the uptake of optional systems in the fleet was generally low. This seriously challenged the ability of NCAPs to quickly identify and confirm (based on real-world evidence) those technologies that delivered a true benefit to the consumer and to society. Consequently, the risk grew that the consumer ratings were becoming less relevant in the eyes of the public and the industry.

From 2012 onwards, NCAP’s and the regulator’s focus on ADAS has accelerated, and spearheaded by NHTSA, IIHS, and Euro NCAP, vehicles have been increasingly credited for offering certain recommended advanced technologies. This has educated drivers about how these systems operate and helped change the consumer’s perspective on ADAS from “great gadgets” to “must have” technology.

Autonomous Emergency Braking

Autonomous Emergency Braking (AEB) is without doubt the most important active safety technology that has emerged since ESC. Using sensors such as radar, lasers, and cameras to identify other vehicles or other road users, AEB automatically applies the brakes if the driver does not respond in time, to avoid or mitigate a collision, saving countless lives, injuries, and inconvenience. Systems are most effective at lower speeds (<40 km/h) where more than 75% of rear-end crashes occur, but they are also valuable in mitigating the devastating effects of higher speed crashes by reducing impact speeds, if a crash cannot be avoided.

AEB, or Crash Imminent Braking (CIB), was one of the technologies covered under the Crash Avoidance Metrics Partnership (CAMP) (National Highway Traffic Safety Administration 2002) between NHTSA and the American auto industry. CAMP was established in the mid-1990s to accelerate the implementation of crash avoidance countermeasures in passenger cars. Based on the groundwork by CAMP and their own research activities, NHTSA began recommending Forward collision warning (FCW) systems to consumers starting with the 2011 model year. NHTSA recently announced that it would include AEB systems (crash imminent braking and dynamic brake support) as a recommended technology and test such systems starting with model year 2018 vehicles (National Highway Traffic Safety Administration 2015).

Within Europe, four main initiatives have actively contributed to development of test procedures for assessing AEB and forward collision warning systems for car-to-car crashes. ADAC, with support from automotive suppliers Continental and Bosch, developed a standardized inflatable vehicle test target (Sandner 2013) in order to perform a comparative test of AEB systems on high-end vehicles. The RCAR Autonomous Emergency Braking group (Hulshof et al. 2013), led by Thatcham Research, designed a testing and (insurance) rating approach for AEB systems. The European Commission sponsored research project ASSESS (Assessment of Integrated Vehicle Safety Systems for improved vehicle safety) (European Commission 2009) and the German initiative led by DEKRA, called Advanced Forward-Looking Safety Systems (vFSS) (Berg et al. 2011), had similar project goals: to develop harmonized and standardized assessment procedures and related tools for selected integrated safety systems. Based on the outcome of these research projects, Euro NCAP adopted both low-speed and high-speed AEB systems in the rating scheme in 2014. In 2016, the first AEB pedestrian test was added to provide an incentive for systems with advanced detection capabilities (Grover et al. 2015), followed by AEB cyclist test in 2018 (Euro NCAP 2018), see Fig. 9.

Fig. 9
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Autonomous Emergency Braking tests for vulnerable road users were first introduced in 2016 for pedestrians and in 2018 for cyclists

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The low-speed “AEB City” test also became an RCAR standard and is similar to the Insurance Institute for Highway Safety Autonomous Emergency Braking Test. Forward collision warning systems (FCWS) have been tested by KNCAP from 2016 onwards. China NCAP has adopted an AEB test protocol in its suite of tests beginning from 2018 and Australasian NCAP aligned with Euro NCAP for AEB and other active safety tests in the same year. Finally, Latin NCAP has announced its plan to evaluate AEB systems from 2020 onwards.

The IIHS states that (low speed) “AEB systems can reduce auto insurance injury claims by as much as 35 percent” (Insurance Institute for Highway Safety 2015). Euro NCAP, with support of the Australasian NCAP, studied the effectiveness of the low-speed AEB systems promoted through the rating scheme since 2014, and showed that low-speed AEB technology leads to a 38% reduction in real-world rear-end crashes, with no significant difference between urban and rural crash benefits (Fildes et al. 2015).

Lane Support Systems

Lane support technologies, such as Lane Departure Warning (LDW) and Lane Keep Assist (LKA), are designed to address single-vehicle run-off-road and head-on crashes. The IIHS (Farmer 2008), NHTSA (Barickman et al. 2007), and others (Scanlon et al. 2015) have studied the potential of these crash avoidance technologies and have estimated big fatal crash reductions. However, current lane support systems often are still not well accepted by consumers, mainly because warning systems are perceived as annoying and unreliable. Perhaps for this reason, clear evidence that lane support technology is delivering on its promise has been slow to emerge. A positive indication has recently come out from field data in Sweden (Sternlund et al. 2016), suggesting LDW/LKA systems are reducing head-on and single-vehicle injury by up to 53%. Also, IIHS has lately found positive, albeit more modest, benefits (Cicchino 2018).

To improve the performance of these systems, US NCAP and Euro NCAP have introduced incentives as part of their respective consumer rating programs. The technology is tested in a straightforward manner by steering the LDW or LKA equipped vehicle slowly towards a solid or dashed line, thus triggering a warning or intervention. While NHTSA’s test can be performed by a driver, Euro NCAP’s test protocol requires path accuracy that can only be performed by driving robots that can also be used for AEB testing.

Recently, more intuitive, intelligent, and integrated systems are entering to the market that can avoid unintended road departures and critical overtaking lane change maneuvers, based on an assessment of threat (Emergency Lane Keeping). The latest Euro NCAP protocols have taken this development into account (Grover and Avery 2017). Besides NHTSA, Euro NCAP, and Australian NCAP, KNCAP has included LKA systems in the rating, while Latin NCAP has announced lane support system testing from 2020 onwards. ASEAN NCAP instead has given priority to Blind Spot Detection, which it sees as key enabler to reduce crashes between cars and powered-two-wheelers (Malaysian Institute of Road Safety Research 2018).

Speed Assistance Systems

Excessive speed is a factor in the causation and severity of many road crashes. In fact, it has a greater effect on the number of accidents and injury severity than almost all other known risk factors. Speed restrictions are intended to promote safe operation of the road network by keeping traffic speeds below the maximum that is appropriate for a given traffic environment. Voluntary speed assistance systems (SAS) are a means to assist drivers to adhere to speed limits, by warning and/or effectively limiting the speed of the vehicle. The only technical requirements for such devices are laid down in United Nations Regulation No. 89 “Speed Limitation Devices,” which is not mandatory in Europe and does not specifically apply to M1 passenger cars.

Starting from 2009, Euro NCAP has rewarded manually set and driver advised speed limitation devices which meet the basic requirements of United Nations Regulation No. 89 but have additional functionality with regards to the warnings given and the ability to be set-at-speed. By doing so, Euro NCAP has created a first incentive to manufacturers to promote such speed-limitation devices, to make them available on more models and to fit them as standard equipment (Schram et al. 2013). Around 90% of vehicles achieving a five-star rating from Euro NCAP in recent years have a speed-limitation device, usually in combination with a cruise control system.

Recently, more advanced speed assistance systems have been introduced onto the market which are able to inform the driver of the speed limit at the vehicle’s current position, based on digital speed maps and/or traffic sign recognition. The Euro NCAP rating system also encourages these speed limit information functions (SLIF). Although there are still limitations to these technologies, intelligent speed assistance systems that combine speed limit information and (over-rideable) speed-limitation, have much greater potential and will be more readily acceptable to the public. As a result, Euro NCAP extended the speed assistance protocol in 2013 to include the latest generation of Intelligent Speed Assistance (ISA) systems.

In 2019, the European Parliament has given the green light to new minimum EU vehicle safety requirements that will come into force from 2022, including overridable Intelligent Speed Assistance for passenger cars, vans, and buses (European Parliament 2019). The availability and popularity of Speed Assistance systems in other regions is still lagging, despite excess speed being one of the leading causes for crashes worldwide. Australian NCAP, KNCAP, C-NCAP, and Latin NCAP are promoting the technology as part of the safety rating to improve update in the market .

Combining Passive and Active Safety

NCAPs have been successfully promoting many different vehicle safety technologies as part of their programs but as more tests have been included, it also has become more difficult for consumers to understand and digest the ratings. Several approaches were adopted to deal with the situation of emerging advanced technology in the respective rating systems. In US NCAP, vehicles earn ratings of 1–5 stars in frontal crash and side crash performance, as well as in rollover resistance. Since 2011, vehicles also earn an Overall Vehicle Score rating, which indicates how the individual 5-Star Safety Ratings combine to reflect a vehicle’s overall safety. NHTSA has utilized NCAP to encourage automakers to add advanced safety features on a voluntary basis and recently began evaluating which ADAS technologies might potentially be included in the near future. Today, the US NCAP checklist includes forward collision warning, lane departure warning, and backup cameras (followed by Autonomous Emergency Braking technology as of MY 2018 models). The checklist gives consumers a quick and easy way to compare the availability of safety features across models although fitment does not affect the star rating.

In 2009, Euro NCAP changed from three individual crash ratings to a single overall safety rating with a maximum of five stars. This overall rating combined the results of assessments in four areas: adult protection, child protection, pedestrian protection, and the new area of safety assist technology. The underlying tests included the full-scale frontal offset, side-impact barrier and pole tests carried over from the previous adult and child protection ratings, the seat tests for whiplash prevention in rear-end crashes and front-end component tests for pedestrian protection. The assessment of Intelligent Seat Belt Reminders was complemented with that of Speed Assistance Systems and Electronic Stability Control as part of Safety Assist. In each area of assessment, scores were calculated as a percentage of the maximum points available and a weighted sum of these scores indicated the car’s overall all-round performance. The testing of low and higher speed Autonomous Emergency Braking as well as Lane Support systems was added in 2014. The latest update of the Euro NCAP rating is the addition of Autonomous Emergency Braking technology for pedestrians and pedal cyclists.

Other NCAPs responded with changes to the rating systems, which sit in between the “encompass all” approach of Euro NCAP and the advisory approach of US NCAP. For example, to qualify for IIHS’s Top Safety Pick, a vehicle must earn good ratings in five crashworthiness tests – small overlap front, moderate overlap front, side, roof strength, and head restraints – as well as a basic rating for front crash prevention, its low-speed Autonomous Emergency Braking technology test. To qualify for Top Safety Pick+, a vehicle must earn good ratings in the five crashworthiness tests, an advanced or superior rating for front crash prevention and a good headlight rating.

Until recently, the Australasian NCAP star rating was based on the vehicle’s performance in frontal offset, side barrier, and pole crash tests, as well as pedestrian and whiplash tests. To earn five stars, it also required key features such as SBR on front and rear fixed seats, head protecting technology (curtain bags) for front and rear seat, three-point seat belts for all forward-facing seats and ESC. This scheme was extended with a “tick-box” approach, based on a menu of Safety Assist Technologies (referred to as “additional SAT”), that included many potential technologies. In 2018, Australasian NCAP aligned their tests, criteria, and rating scheme with Euro NCAP, apart from minor differences due to local regulations.

Almost all major NCAP programs have recently introduced rating changes to accommodate the testing of avoidance systems. China NCAP has begun AEB testing as part of their star rating. Other NCAPs like Korean, Japan NCAP, Latin and ASEAN NCAP have moved to an overall rating system and/or are in the process of making changes to accommodate more crash avoidance technologies. Finally, NHTSA is considering a new approach to determining a vehicle’s overall five-star rating that may, for the first time, incorporate advanced crash avoidance technology features, along with ratings for crashworthiness and pedestrian protection.

Consumer Information in the Era of Automation

The idea of assisted driving, automated driving, and self-driving cars has been widely aired in technical discussions and in media coverage over the last years. The rapid development of electronic safety systems and communication over the air has made the concept possible and the first cars have come onto the market, which are able, with driver oversight, to “drive” themselves in controlled situations. The established vehicle industry is active in this field but also new players, such as Waymo, Zoox, UBER, Lyft, etc., are trialling self-driving cars. There is no doubt that greater automation will lead to a revolution in safety, putting it above all other requirements and characteristics of a car. Not only will the self-driving car have the technology to sense, avoid, and mitigate in potential crash scenarios, it will also drive in a safer manner. Besides that, the vehicle must always carry the safety elements and technologies to intervene and protect the occupants when necessary (the “backup safety”).

However, as Volvo, Mercedes, Tesla, GM, and others are launching their first “auto-pilot,” Highway Driving Assistant systems, it is not easy to see to what extent safety on the roads may be affected in the short term. Cars with increasing levels of automation will allow drivers to delegate control, taking their eyes of the road and engage in activities unrelated to driving. Drivers, however, must resume control in conditions not yet supported, such as adverse weather or complex traffic conditions. Drivers need enough time to regain situation awareness in order to effectively take back control, a challenge that may become more critical the longer the driver has been “out of the loop.” So far, this means that drivers must always continue to monitor the vehicle drive itself and the systems can only be used safely in restricted traffic situations that represent a relatively low crash risk in the first place.

Unfortunately, the automated driving media hype is confusing consumers, as many drivers believe they can purchase a self-driving car right now. According to a study, commissioned by Thatcham Research, Euro NCAP, and Global NCAP (Thatcham Research 2019), 71% of motorists believe that they can buy a self-driving car today, while 11% would be tempted to have a brief nap while using current “Highway Assist” systems. The research was conducted throughout October 2018 and included 1567 car owners from China, France, Germany, Italy, Spain, the UK, and the USA.

Tests of cooperative driving systems such as “Highway Assist systems” by IIHS (Insurance Institute for Highway Safety 2018), Euro NCAP (Euro NCAP 2018), and others clearly demonstrate that cars on the market today can provide driver assistance, but this should not be confused with automated driving. The driver remains fully responsible for safe driving. Used correctly, this technology can help the driver to maintain a safe distance, speed, and to stay within the lane, but these systems should not be used in situations they are not designed for and should not be relied upon as an alternative to safe and controlled driving. The lack of driver training and standardized controls, symbols and names for these features, is further complicating matters for consumers. For the time being, NCAPs can play an important role in promoting realistic expectation among consumers and highlighting the need for constant driver vigilance.

The industry is working towards a safer system by adding Vehicle-to-Everything (V2X) communication, improved 360 degrees sensing capabilities, driver state monitoring, and smarter algorithms, which will further reduce driver engagement risks. Hands-free driving will open the door to completely new concepts that are offering a high degree of flexibility in design, layout, and seating arrangements. From an occupant crash protection perspective, this means that restraint systems will probably become more seat-centric and that the classic approach where belt and bags systems are validated against a limited number of load cases and occupant seating positions will need to be revisited. The continuous situation-awareness of the vehicle itself, facilitated by surround sensors and communication, and that of the occupants inside, will allow for more integrated safety functions across sensors and actuators. This, in turn, can improve pre-crash interventions and enhance the efficiency of passive safety systems.

With over 1.2 billion vehicles on the world’s roads and the average age of vehicles on the road rising to over 10 years, it is a given that automated and self-driving vehicles will have to operate in a mixed traffic environment with manually driven cars for many years to come. The accident distribution of automated cars will be notably different from today’s cars as, although they are expected to cause fewer crashes, they will still be involved in accidents with older, manually driven vehicles and other road users. Improving the level of safety of all vehicles on the road, regardless of level of automation, therefore deserves our continued attention. This remains particularly true for the vehicles sold in the most low-income countries, which do not meet minimum safety standards and trail behind the advancements made in high-income markets over the last decades .

NCAP Challenges for the Next Decade

Over the years, NCAP has offered a mechanism by which improved insight or technology can be introduced into the design of new vehicles much faster than would otherwise be possible. Gradually, the vehicle industry has come to terms with consumer ratings and has learned to use the system to its advantage in each market. This has greatly helped to democratize car safety and has improved consumer awareness around the world, important steps in achieving the Vision Zero goal to eliminate traffic casualties.

As the automotive industry is rapidly changing and new forms of mobility become available, the formal role that NCAPs traditionally had in influencing the market through consumer information will no doubt become more difficult to play in the future. One of the challenges for NCAPs will be who actually will be the consumer in the future – will private individuals still be buying cars as they do now 10 years from today? Will safety continue to sell, now that that most cars offer many systems as standard and our focus has radically shifted towards the promotion of sustainable mobility and reducing the impacts of climate change? And will consumers, even if it is just as service users, be allowed to have a say in setting minimum levels of safety for automated vehicles?

The answers to these and many other questions will need to be found the coming years. Even so, in the era of false information and differing opinions, there remains a need for truthful and transparent information, and so there will be plenty of opportunities for NCAPs to continue to make a difference.

Correlation with Real-Life Injury Risks?

For NCAP to maintain its credibility, the overall indication of the safety level that is provided by a safety rating must be a valid prediction when considering severe or fatal injuries or injurious crash involvement. On a technology level, a positive correlation between improved safety performance and the reduction of real-life injuries can often be determined, as shown by the numerous examples mentioned before, but in most cases, consistent field data only emerges several years after countermeasures have penetrated the market. An important challenge for NCAPs worldwide therefore continues to lie in the early identification of live-saving technologies, such that these organizations can effectively play their role as catalysts.

For this, a robust system for the collection, management, and analysis of regional road accident data is essential. Accurate information from before, during, and after an accident, including on the driver state, helps to determine accident causation and allows accident researchers to assess the effectiveness of countermeasures.

Furthermore, as most new safety technology is fitted as optional and, in the case of ADAS not always default on, it is important that researchers can independently verify which technology was fitted and in use on when a vehicle was involved in a crash?

On a more general level, it is more challenging to determine whether there is a correlation between star ratings and benefits in real-life impacts. Lie and Tingvall (2002) found that in car-to-car collisions, cars with three or four stars were found to be approximately 30% safer when compared with two-star cars or cars without a Euro NCAP score. The results indicated a 12% per star risk reduction for severe and fatal injuries. A few years later, these conclusions were supported by more broad international study, SARAC II (European Commission 2006); however, it was noted that significant variation remained in the measures of injury outcome in real crashes for specific vehicles within each Euro NCAP score category. Kullgren et al. (2010) again showed Euro NCAP crash tests to be highly correlated with serious crash performance, confirming their relevance for evaluating real-world crash performance. Good concordance was also found between Euro NCAP and Folksam (insurance claims based) crash and injury ratings. More recently, Kullgren et al. (2019) reviewed the developments in car crash safety in cars launched since the 1980s based on real-world data and reexamined how Euro NCAP crash test results predict the outcome in real-world crashes. It was found that Euro NCAP crash test ratings mirror real-world injury outcomes for all injury severities studied. Comparing five-star with two-star rated cars, the proportion of AIS 3+ injuries was 34% lower.

Note that the above studies focused on crashworthiness improvements and excluded active safety or driver assist technologies. To further develop rating systems that reward the overall safety of a vehicle from a self and partner protection point of view, the real-life impact of the combination of passive and active safety measures still needs to be better understood .

Vehicle Safety in Low- and Middle-Income Countries

As the Academic Expert Group for the third Global Ministerial Conference on Road Safety (Global Ministerial Conference on Road Safety 2019) points out, only 40 countries have implemented 7 or 8 of the critical safety standards identified in the 2018 Global Status Report on Road Safety, whereas 124 countries, many of them low- and middle-income nations, have implemented none or just one of these standards. Especially in developing markets, that are showing extraordinary growth in the number of vehicles in use, this is a major challenge as without such standards, manufacturers can easily cut back on safety to boost profitability.

To bring safer cars to these regions, a combined approach of legislative action and raising consumer awareness is most efficient, as has been illustrated in India recently by the efforts of Global NCAP and the Indian government (Ministry of Road Transport and Highways 2019) .

Harmonization of Standards

But whereas NCAP’s strength is its ability to follow closely the technology development by industry and take account of local market circumstances, it is also true that this has led to a wide variety of test conditions and inherently different rating schemes applied around the world. The criticism about the lack of harmonization is certainly justified in some instances, when different test speeds, barriers and crash dummies are used to evaluate a car’s performance in what is essentially the same real-world crash scenario. On the other hand, there are many good reasons too to be different, not in the least because the cars built around the world are so diverse and must often meet local regulations.

Global NCAP provides a cooperation platform for NCAPs and similar organizations around the world to share best practice, to further exchange information, and to promote the use of consumer information to encourage the manufacture of safer cars across the global automotive market facilitates the dialog between NCAPs. Recently, more efforts have gone into cooperation between NCAP programs at the development phase as well, for instance, on the definition of a common 3D “soft” vehicle target for AEB testing (Grover et al. 2017).

Population Diversity

In most markets, new cars today are safer than they were a decade ago thanks to improved test standards, crumple zones, seatbelts, and airbags, which all help to protect occupants in a crash. While most occupant safety measures can be considered mature, more could and should be done to improve their robustness and effectiveness for the general diversity of vehicle occupants and crash scenarios.

Standard crash tests focus primarily on a limited number of sizes of occupants, namely the mid-sized male, small female, and large male. The effect of variation in age, gender, race, and corpulence must be better understood so that vehicle safety systems can work to the benefit of all. Test methods and injury criteria, especially those applied in regulation and by NCAPs, must drive more robust performance for the population of car occupants and vulnerable road users .

Encouraging ADAS

Crash avoidance systems can help prevent accidents from happening in the first place. Considering the time any new technology needs to penetrate the vehicle fleet, it is important that they are effectively deployed to address the above key accident scenarios, including those that involve other road users and commercial vehicles.

Today, the global uptake of crash avoidance technology is still developing: a large variety of systems is available, some are standard in developed markets, but only offered as optional elsewhere. As most ADAS are not mandated, the uptake of optional systems is still low and depends greatly on market incentives. The situation is likely to improve as the need for more on-board technologies to support (partial) automated driving will make crash avoidance systems cheaper and more cost-effective across the car fleet. Voluntary agreements to make equipment standard across the fleet – like those announced by US.DOT and IIHS on AEB systems in the USA (Insurance Institute for Highway Safety 2015) – help generate the momentum in the marketplace. In Europe, Euro NCAP’s five-star system has helped boost the availability of ADAS across the Member States, as is shown from the share of the total cars rated with standard ADAS between 2012 and 2019 (Fig. 10). The situation is about to improve even more from 2022 onwards as the General Safety Regulation (European Parliament 2019) will come into effect, mandating, for the first time, systems like AEB, lane support, and speed assistance for passenger cars and LCVs.

Fig. 10
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Percentage of cars tested per year that is equipped with standard ADAS across the European market. Euro NCAP 2012–2019

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Besides price, the acceptance and volume of advanced technologies are driven largely by how well consumers understand these features and value them. Today, when they are placed on the market, ADAS are often not yet fully mature. Together with the lack of knowledge among drivers, situations in which drivers fail to understand why the vehicle responds or indeed fails to respond in a certain way, can quickly arise. To counter this, consumer ratings must adequately evaluate the complex role of driver behavior and address inconsistencies in information, warning, and intervention strategies across the industry .

From Assisted to Autonomous and Connected Driving

As automation in cars becomes more mainstream, new crash scenarios and priorities may emerge and surveillance systems should be in place to ensure high quality data will be collected on the circumstances of a crash and the role of man and machine. There is a high expectation that vehicle automation will lead to innovations in the in-vehicle environment. This will lead to a potentially more complex loading environment for future restraint systems and will present a major challenge to NCAPs and regulators that must evaluate them.

As long as there are clear categories of crash avoidance systems that address typical accident scenarios and where the contribution of the driver is limited, the “spot testing” approach currently followed by NCAPs will remain beneficial. Verifying the performance on a system level in idealized conditions has the advantage of being able to set clear engineering targets, raise consumer awareness and effectively drive best practice and higher equipment fitment in the market. However, as safety functions become further integrated and vehicles begin to rely on connectivity with infrastructure and other road users – in other words become truly connected – it is unlikely that track testing alone will be sufficiently meaningful or conclusive to steer improvements in industry or to inform the consumer.

Conclusions

Vehicle safety has played an important role in reaching Vision Zero. Whereas regulations set minimum safety standards for motor vehicles in each region and give authorities the power to restrict sales of unfit vehicles, consumer ratings are an effective mechanism to influence the consumer preference and promote new technology entering the market.

Most consumers will have no personal experience by which to judge the crash safety of their car. Are they happy with the level of safety offered? Can they specify what level they want? Can they assess whether this objective has been met? Clearly, without objective and transparent safety information, these questions would be impossible to answer. This underlines the importance of public safety ratings and justifies why NCAPs around the world continue to develop their comparative safety tests. Moreover, it explains why consumer ratings continue to have an impact, not only with consumers but also more and more with public and private fleet managers to help them ensure that their vehicle fleet provides acceptable levels of protection to their employees.

A consumer rating system that is rooted firmly on real life experiences, but which closely follows the technological innovations in the marketplace, can deliver the most benefit for society. For this reason, links to road safety and biomechanical research as well as to the automotive industry are essential. The NCAPs together have achieved much to be proud of, but there is still important work to be done: in low- and middle-income markets to ensure that zero-star cars will be a thing of the past and, in developed markets, to ensure safety remains a priority for car manufacturers, in order to reduce road fatalities and injuries even further.

The NCAP community plans to engage in the roll out of vehicle automation as a way to dramatically improve vehicle safety and safe driving. It will continue to promote best safety practice when vehicles start to have elements fitted which support automated driving and to ensure that the vehicle manufacturer remains responsible for safe operation of the system. Consumer acceptance of these systems and objective, independent reassurance of their performance will play a key part in the transition that is ahead of us.

NCAP has shown that increasing consumer demand for safer cars, combined with exerting pressure on car manufacturers to incorporate better safety features into their vehicles, can make significant improvements to the safety of cars and bring Vision Zero one step closer.