Speed in a high-speed society

Abstract

Speed control is the most important aspect of promoting road safety world-wide. The question is how are speeds developing? The European Transport Safety Council concludes: There is little progress on reducing speeds in Europe. Similar conclusions can be drawn from the US and Australia. Attitude surveys show that people’s answers are not very consistent and represent statements without any strong bearing on norms or behaviour. Many factors are ‘pro-speed’: higher performance vehicles, more comfort, media coverage, etc. Enforcement, particularly with cameras and with section control is efficient, but the scale of adoption is too small. Traffic calming is efficient in cities, but the most obvious measure is one that makes it impossible to drive faster than the speed limit. During the last 30 years, a few trials have taken place which are promising; speeds at or below the speed limit, improved behaviour, and attitudes. The predicted effect is a reduction of up to 50% of fatalities in a regulation-driven scenario and a benefit to cost ratio of 3.5 to 4.8. It is time for authorities to see to it that lower speeds with the help of efficient vehicle-based solutions becomes part of the agenda.

Keywords:

• Speed enforcement
• traffic calming
• speed campaigns
• speed limiter

Introduction

Speed control is the most important aspect of promoting road safety world-wide. There is a very strong statistical and causal relationship between speed and road safety. Even small reductions in travel speed result in significant reductions in road injury and deaths. A 10% reduction in the average speed results in almost a 40% reduction of fatalities on rural roads and a little less on urban roads. (Elvik 2009). The relationship between the speed of traffic and road safety has for a long time been modelled by means of the Power Model. Recently, however, an exponential model has also been proposed to describe the relationship between the mean speed of traffic and road safety (Elvik, 2014). Both these models are based on extensive data, and with respect to road deaths both approaches work well, except at low speeds where the predicted effects are over-estimating the real effects.

Speed has the great advantage that it relates to all potential risks irrespective of environmental factors, infrastructure, road users’ status or any other risk-related factor.

The strong relationship between speed and the risk of crashes/injuries works twofold:

1. The lower the travel speed, the greater the chance of detecting a potential hazard and thereby preventing a crash or decreasing impact speed.

2. The lower the impact speed, the less severe the consequences.

The relationship between speed and risk is well-established scientifically and governments and organizations all over the world appreciate the importance of speed. The UN – General Assembly resolution 64/255 of March 2010 proclaimed 2011–2020 the Decade of Action for Road Safety. A Plan of Action was prepared for the decade where it was stated that one of the measures was to produce effective interventions ‘by effective speed management by police and through the use of traffic-calming measures’.

Speed control is high on the WHO agenda. However, an analysis made of how the world’s 10 most populous countries – accounting for almost 4.2 billion people and 56% of the world’s road traffic deaths (703,000) meets the best practice legislations shows that no country meets the best practice criteria for speed (WHO, 2015).

Setting the relevant speed limits is one side of the coin. The other side is the acceptance and compliance with the limits. Estimates from some 50 OECD and ECMT-countries show that ‘Speeding – i.e., excessive and inappropriate speed – is a widespread social problem as, typically, at any time 50% of drivers are above the speed limits’ (OECD/ECMT, 2006). The outcome due to non-compliance is dramatic: if everybody was keeping the speed limit always, then the fatalities would drop by between 20% and 50% (Høye et al., 2014; Simcic & Townsend, 2008; STA, 2015).

History and the present situation

It is difficult to find comparisons over time. Valid data are not available even from Europe which includes some of the highest motorised countries. The European Transport Safety Council (ETSC) in 2006 established a number of performance indicators (PIN) to be used as surrogates in order to analyse safety performance (Achterberg, 2007). An initial report gives an overview of European countries’ performance in five areas of road safety (Achterberg, 2007). Regarding speed, the ETSC concludes:

The impact of speed on road traffic crashes has been studied extensively, and measures to reduce speed are known. Yet there is little progress on reducing speeds in Europe. Average speeds and the number of speed limit violations remain high with only few encouraging signs.¹

In a follow-up report regarding speed compliance, the conclusion is that on urban roads (37% of all fatalities) there has been ‘mixed progress in reducing mean speeds’.² On rural roads (55% of all fatalities) there is an ‘overall lack of progress in reducing mean speeds’. On motorways (8% of all fatalities) ‘progress in terms of annual change in average speed on motorways is mixed’. The proportion of drivers exceeding the prevailing speed limit is for the three types of road 35–75%, 9–63% and 23–59%, respectively. This should be seen in view of the fact that these data represent a rather small part of all EU-countries.

Australia has also been working seriously on issues concerning speed control. The main conclusion that can be drawn from Australian data are that on most roads, in most states, there is a downward trend regarding mean speeds, however, with a median reduction per year of 0.3 km/h. Compliance rate varied between 40% and 80%.

It appears that there are no examples of significantly reduced speeds anywhere.

Attitudes

In a European study SARTRE4 12,507 car drivers and other road users in Europe were interviewed in (SARTRE group, 2012). Speed-related findings showed that drivers in Europe have a relatively positive attitude towards speeding, although this tends to be most common among young drivers and men. The attitude towards speed enforcement and speed reduction tends to be rather negative, although a fairly large proportion would not object to punishments becoming more severe. A large proportion was opposed to reducing the speed limit to 30 km/h in built-up areas.

The main conclusion is that measures to prevent speeding seem to have a rather low priority among people in Europe, and a similar conclusion can be drawn from the US and Australia. The answers are not very consistent. The vital question is to what extent can these statements by the public represent anything more than just statements without any strong bearing on norms or behaviour.

The car regime

The ‘car regime’ is the regime in which reinforcing the use of the automobile as the dominant mode of transportation takes place. Marletto (2011) has produced a comprehensive analysis of the importance of this ‘regime’. He explains: ‘the car regime was established thanks to the ability of purposeful private actors to use the technology of internal combustion to influence markets and institutions, and finally society as a whole’. Attempts to deliberately destabilize the automobility regime has shown that this regime is based on a strong actor network involving the automobile industry (and associated sectors), transportation policy, and customer behaviour, which mutually reinforce each other and creates a highly stable regime (Hoffmann, Weyer, & Longen, 2017).

The regime of auto mobility produces negative externalities, such as road congestion, pollution, traffic accidents, noise, loss of space in urban areas, dependency on oil and global warming. A central issue in research is, therefore, how to discontinue these incumbent socio-technical regimes (Hoffmann et al., 2017). In the following we will approach the behaviour of the ‘car regime’ in relation to speed.

Power and speeds

In an analysis by Høye et al. (2014) five relevant studies on speed and safety were identified, four of which indicate significant increase of accidents with increasing power. However, from 1970s onward the speed performance of private cars has been steadily increasing, and today most cars can reach the maximum speed of 200–250 km/h. But research about the relationship between vehicle performance – speed and acceleration – and safety has not been given any priority by industry or governments.

A critical question in this context is how these issues of speed and safety would influence the situation in low and middle-income countries (LMIC). To what extent are heavy, high-performing cars compatible with all the intermediate transport vehicles (tuk-tuks, three-wheeled taxis, etc.) and other small vehicles and vulnerable road users?

Comfort, speed and safety

One special aspect on travel speed is that related to comfort. New technology has made it possible to make very advanced comfort systems. One example of this is the so-called Magic Body Control developed by Mercedes Benz. A clever combination of sensors and suspension adaptation transforms the new S-Class into a ‘flying carpet …’.³ In promoting the system, it is demonstrated how the system eliminates the discomfort perceived by car users when negotiating a bumpy road, including when they negotiate a speed hump. As the latter is built with the purpose of creating discomfort when the speed is ‘too high’ it would of course be very important to find out how travel speed – and thereby safety – is influenced by this kind of comfort device.

Media

It is also important to understand the role of the media in the car regime. There is a large interdependence between industry and media. Advertising accounts for a large share of a newspaper’s total revenues around the world (Beattie, Durante, Knight, & Sen, 2017). Car manufacturers are among the newspapers’ largest advertisers. As of 2006, the total advertising spend by the automotive sector amounted to over 20 billion dollars, 40% of which benefited the print media. Newspapers’ reliance on advertising raises the concern that editorial decisions may be vulnerable to the influence of advertisers, especially the biggest ones (Beattie et al., 2017).

Measures not initiated by the car regime

Speed limit changes

Available evidence indicates that lowering the speed limit lowers travel speeds provided that there is some element of enforcement. A Norwegian study found that decreasing the speed limit produced a reduction of mean speeds which is considerably less than the change of the limit (Elvik, 2014). A reduction of the speed limit by 10 and 20 km/h resulted in a reduction of mean speeds by between 2.5–3.5 and 7.5–9 km/h respectively.⁴ On a 90 km/h road the effect would be a reduction of fatalities between 11–15% and 29–34% if the power model is used to predict the outcome based on change of average speeds. Even though there is a significant decrease of fatalities, there is a risk that lower compliance with speed rules, might have negative long-term effects with less respect for speed management activities.

Campaigns

Speed limiting campaigns have a very limited effect, only minus 4% on all accidents. Besides, it seems as if the effect of the campaigns goes down over time. In the 1980s, the overall effect was minus 16% which came down to minus 5% in 2000–2010 (Høye et al., 2014). This evidence of the limited effect is supported by the EU Information page n Education and Publicity Campaigns which states that the effect of education and publicity on its own is likely to be very limited in changing actual speed behaviour.⁵

Enforcement

Manual with mobile control

According to meta-analysis by Høye et al. (2014) the summarized effect for all types of mobile controls by the police is a decrease of injury crashes by 17%. It seems to be the same no matter whether the speed control teams are hidden or visible.

Single speed cameras

Speed cameras seem to be one of the few measures that can have quite a significant effect on speed behaviour on rural roads. A number of meta analyses have been done on this subject:

• Høye et al. (2014): Speed cameras were found to reduce total crash numbers by about 20%. The greatest effect was found at the camera locations and only a slight reduction was found at a distance of two or more kilometres from the speed cameras. Fatal crashes were found to be reduced by 51%, this result may however be affected by regression to the mean.

• The level of evidence is relatively poor (Pilkington & Kinra, 2005). Wilson, Willis, Hendrikz, Le Brocque, and Bellamy (2010) agree on the quality, but add: ‘Despite the methodological limitations …. the consistency of reported reductions in speed and crash outcomes across all studies show that speed cameras are a worthwhile intervention for reducing the number of road traffic injuries’.

Double speed cameras

A considerable improvement in speed camera enforcement methods is the use of section control systems which compare the passing of vehicles at two specific spots. It measures the speed of the vehicle, in accordance with the distance between the two spots and the time needed to cover that distance. Section control is more effective with a reduction of average driving speed by up to 10% (from approx. 90 to 80 km/h (Ragnøy, 2011), with a compliance rate of very close to 100% (Høye et al., 2014). They studied the safety effects of section control at 14 sites in Norway. The number of killed or severely injured was found to reduce by 49% at the section control sites. Downstream of the section control sites (up to 3 km in each direction) injury crashes were found to be significantly reduced by 46%. However, the size of the effects that was found should be interpreted with caution because of the relatively short after periods for some of the sites and the sensitivity of the results to the outcomes of individual crashes. Besides, this method is more expensive and complicated to implement, so it is still a question of how cost-effective it is.

Infrastructure

Traffic calming

‘Traffic calming’ (TC) refers to a combination of network planning and engineering measures to enhance road safety as well as other aspects of liveability for the citizens’ (van Schagen, 2003).

The success of TC is related to speeds. Calming means low speeds, primarily 30 km/h. To reach these low-speed measures have to be effective. There are two basic elements: speed humps and small roundabouts. These two fulfil the criteria of maximum 30 km/h, if they are of the right design. Evaluations have shown that speed calming measures are the most important contributing factor to the injury reduction in urban areas. Moreover, it has been shown that such measures are good investments, with a high rate return on investment (ITF, 2016).

Reducing vehicle speeds may be one of the most effective interventions to stem traffic crashes in low-income countries. In some LMICs, the use of speed camera strategies may not be appropriate in some situations, however, the alternative of TC should be effective in most situations. More research needs to be done for details of roundabout and other TC design for locations with high shares of pedestrian and motorcycle traffic.

The International Road Assessment Programme (iRAP)

iRAP provide tools and training to assist countries to make roads safe.⁶ The main activity is to inspect high-risk roads and develop Star Ratings and Safer Roads Investment Plans, and track road safety performance so that funding agencies can assess the benefits of their investments.

The document iRAP Star Rating and Investment Plan – Implementation Support Guide (iRAP, 2017) is analysed with regard to how speed is treated generally and in relation to the star rating. Below are some of the central statements:

• ……you can adjust the speed limit and 85th percentile speed attributes in the Speeds tab.

• It is important to ensure that improvements such as lane widening, resurfacing, additional lanes and paved shoulders do not result in excessive vehicle speeds, …. In such cases vehicle speeds must be effectively managed in order to minimise risk….

• … Those sections where speed restrictions applied, incorporating traffic calming features such as road humps and transverse rumble strips were coded with speed set to ‘less than 40km/h’.…… However, it is not clear what road engineering standards would be used to ensure that no vehicles exceed the different speed limits.

To be able to control how speed is treated, case studies presented by iRAP are used. There is one with special bearing on speeds, namely the pedestrian channelization project in Wuhan, China. Even though many of the proposed measures seem to be valid from a safety point of view, there does not seem to be any speed reduction concept. Most importantly, when discussing pedestrians the focus in this project seems to be ‘efficiency for vehicles’, ‘to clear the junction quickly’ and similar aspects (Frame, 2009). So, the conclusion must be that iRAP so far, has not demonstrated any efficient speed reducing strategies, except for TC in built-up areas.

ISA and speed limiters

The most obvious measure to treat non-compliance of speed rules – the vehicle speed limiter – is not on the agenda yet. A system that makes it impossible to drive faster than the speed limit, everywhere, and at all times should have an enormous potential compared with all other measures. All measures that are used today – infrastructure, enforcement, etc. – are all very limited in scope. Thus, the potential of the effectiveness of speed limiters is extremely high, but the interest in the ‘car regime’ has been very limited. The concept of speed limiters in all vehicles seems to be abandoned. Instead, there is now one common concept only, called ISA-Intelligent Speed Adaptation. ISA is the general term for advanced systems in which the vehicle knows the speed limit at any given location and is capable of using that information to give feedback to the driver by some kind of signal, auditory, visually or haptic (resistance in the acceleration or gas pedal). The main point is that the use so far is voluntary; you can always override the system, in one way or the other. The ISA has been introduced in many car models recently.

Currently speed limiters already in buses and trucks in many countries. However, these limiters are set on plus 10 km/h in relation to the highest speed limit on the roads in the country. This means that it is still possible to exceed the speed limit on all roads, especially on roads with lower speed limit than the maximum. The result is, therefore, very limited effects in total even if all vehicles are so equipped (Vaa, Assum, & Elvik, 2012).

Speed Limiters also exist in some private cars, but only in very special settings. In Germany, the car industries themselves had agreed on installing speed limiters in their cars, set to 250 km/h⁷. However, since Italian-made cars can go faster, Mercedes-Benz and BMW now also allow customers to get their cars without this limiter.

From the 1980s, there have been a number of, authority driven, empirical trials of ISA with various degree of demands regarding speed compliance, from speed limiter type to various other solutions with different degree of voluntary uses. In France, the earliest study was that of Malaterre and Saad (1984) who tested vehicles equipped with two different ISA systems. The first system (System A) comprised a control panel placed near the steering wheel with fixed speed limit controls. Once the vehicle reached the selected speed limit, the accelerator pedal became stiffer, but this hard point could be overridden if necessary. This was the equivalent of a ‘mandatory’ system. The second system (System B) involved a level, which the driver used to set a given driving speed, beyond which the accelerator pedal had no effect. A kick down system enabled the vehicle to override the chosen speed for as long as the pedal-stayed depressed. This was the equivalent of a ‘voluntary’ system of speed control. A comparison between the two systems showed that the correct speed was much higher in the first case, 72% vs. 11% (speed limit: 60 km/h) and 96% vs. 42% (speed limit: 90 km/h).

In Tilburg, the Netherlands, the Dutch Ministry of Transport ran a mandatory ISA field test from 1999 to 2000. Twenty passenger cars were used and a bus (Information collected from (Driscoll, Page, Lassarre, & Ehrlich, 2007; Loon & Duynstee, 2001). The test zone contained 30, 50 and 80 km/h speed limits. The ISA system as tested in the Netherlands is technologically feasible. The ISA test in Tilburg has had a positive effect on driving behavior and speed patterns. Ninety-five percentile speeds went from well over speed limit on 30 and 50 km/h roads without the ISA to somewhat under with the ISA. The ISA Tilburg test shows that great deal of public support can be gained, adequate communication however is essential.

In Eslöv, Sweden, 25 persons driving their own cars got them equipped with speed limiter which was automatically activated when the car was inside the built-up area of the city. The trial went on for half a year, in the mid-1990s (Almqvist, 2006). Speeding was eliminated almost entirely for these 25 people (small technical problems led to some – but minor excessive speeds). The effect of the speed limiter was clearly seen on major streets where speeds were considerably higher than the allowed 50 km/h, the longitudinal speeds were strongly harmonized and kept under the speed limit with the speed limiter. Behavioral observations showed an improvement in behavior in interactions; drivers more often giving the right of way to pedestrians, cyclists and other vehicles. The test drivers stated that the speed limiter function should be made mandatory.

In 2002, the French Ministry of Transport launched the LAVIA Intelligent Speed Adaptation system, according to the road network and system mode, based on observed driving speeds, distributions of crash severity and crash injury risk. Two French automotive manufacturers PSA and Renault participated with cars in the project (Driscoll et al., 2007). The potential safety benefits of the different versions, based on observed driving speeds, distributions of crash severity and crash injury risk are given for car frontal and side impacts. Together they represent 80% of all serious and fatal injuries in France. Of the three system modes tested (advisory, driver select, mandatory), the results suggest that driver select would most significantly reduce serious injuries and death.

In Leeds, UK, an on-road study was carried out, as part of an External Vehicle Speed Control project (EVSC). A vehicle was equipped with two versions of EVSC, Driver Select and Mandatory. The Mandatory system trial in this experiment successfully reduced speeds, particularly in areas where drivers are renowned to being poor at adapting their speed. There were no negative behavioral compensation effects. Although drivers were initially unfavorable towards the mandatory system, they reported that driving with the system was safer due to enhanced awareness of potential hazards. The effectiveness of the Driver Select system is roughly half that of the mandatory one (Carsten & Fowkes, 2000).

Prediction based on actual speed changes observed in the ISA project in the UK is that an ISA system targeted purely at compliance with existing speed limits could, in its strongest variant (i.e., a non-over-rideable version), deliver a 29% reduction in injury accidents (Carsten, 2012). Applying the power model, Nilsson (2004) and Elvik (2014), that translates into a 50% reduction of fatal accidents.

The combined results of all the studies clearly indicate that there is a great potential of mandating speed limiters from a behavioral and safety point of view. All trials but the French Lavia-project have clearly demonstrated the benefits of an ‘Authority select’ mode. And the predicted effect of a reduction of 50% of fatalities – as in the UK-project – is verified by the EU-funded and SRA coordinated project PROSPER. The PROSPER project calculated crash reductions in fatalities after trials in six countries between 19% and 28%, in a market-driven scenario. Even higher reductions were predicted for a regulated scenario—between 26% and 50%. Benefits are generally larger on urban roads and are also larger if more intervening forms of ISA are applied. (EC.Europa.eu, 2019). PROSPER also estimated benefit to cost ratios ranging from 2.0 to 3.5 and 3.5 to 4.8 or market-driven and regulation-driven, respectively.

It is important to add to this picture that the car industry has contributed a great deal in improving the safety of car occupants by improving the crashworthiness of cars. Much of this work has been enhanced thanks to the New Car Assessment Programme (NCAP) where the industry has been encouraged – and, in practise, forced – to improve the safety performance of vehicles.⁸ Lately EuroNCAP has introduced assessment of speed assistance technologies which could be the accelerating factor for the implementation of ISA. However, Euro NCAP only promotes installation of voluntary Systems.⁹ ‘Speed Assistance’ has not a strong impact on the EuroNCAP score. It only contributes to one-fifth of a ‘Safety Assist’ score, and the assessment does not guarantee any actual change of speeds.

Active safety measures and naturalistic driving

During the last decades, the car industry has been focusing more and more on active safety measures, e.g. Electronic Stability Control (ESC). The technology needs understanding of driver behaviour in real world. The first Naturalistic Driving Study (NDS) was carried out in the US (Dingus et al., 2006). One-hundred drivers were involved. ‘A primary goal was to provide vital exposure and pre-crash data necessary for understanding causes of crashes, supporting the development and refinement of crash avoidance countermeasures….’. EU has supported a similar approach: UDRIVE – European Naturalistic Driving Study. UDRIVE has defined risky behaviour where ‘Speeding (speed choice in relation to speed limit, max speed, etc.)’ is one example (Eenink, Barnard, Baumann, Augros, and Utesch, 2014). In theory, there should be a great opportunity to study the naturalistic speed behaviour in relation to speed limits, also speed adaptation behaviour and risks.

Actors

There are many global actors including the UN, WHO, IRTAD, iRAP, GRSP, Bloomberg Philanthropies and WRI who are promoting road safety around the world. There are also big consultant firms and other NGOs operating on different levels and in different scales. Road safety has become good business for many.

WHO is of course a central actor, coordinating activities all over the world. In a WHO discussion paper, the target for safer road users is: ‘Reduce the proportion of vehicles travelling over the posted speed limit by at least 10% per year’, which should be 50 km/h or 30 km/h where there are many vulnerable road users. An ambitious goal, however, so far there is almost no progress in achieving these goals and targets. The main contributor, namely Bloomberg Philanthropies funded ‘Road Safety in 10 Countries Project (RS-10)’ with US$125 million over a 5-year timeline (2010–2014).¹⁰

The primary goal of RS-10 was to reduce deaths and serious injuries in LMICs by focusing on proven preventive and care interventions. The project targeted 10 countries that account for almost half (48%) of all traffic deaths globally. Three of the countries had speed-related projects.

In China, interventions to curb speeding and drink driving were implemented in the cities of Suzhou and Dalian since late 2010. Ongoing effect of these activities was evaluated, and analysis of crash statistics in the two cities. We find that thus far, the prevalence of speeding has not reduced in either city with the notable exception of one site in Dalian, where the percentage of speeding vehicles declined from nearly 70% to below 10% after an interval-based speed enforcement system was installed. The broader deployment of such speed control technologies across China and other countries should be explored. (Bhalla et al., 2013). It has become known by the author that new, positive, results have emerged from other parts and other studies in China. It has, however, not yet been possible to retrieve the findings of these studies to date.

In Turkey, interventions were made between 2010 and 2014 in two cities. It included social marketing campaigns; enhanced police enforcement; legislative advocacy; and training for police, journalists, and academics. Findings revealed limited improvements in speed reductions.

Interventions were carried out in two provinces in Russia, where enforcement activities had some obvious impact: The main findings were: (a) In Lipetskaya, the overall prevalence of speeding declined from 47.0% to 30.4% from July 2011 to October 2014). (b) a similar pattern was observed in Ivanovskaya where the prevalence of speeding decreased from 54.6% to 46.6% (from March 2012 to October 2014). The decline in speeding was likely associated with enhanced enforcement campaigns, consisting of increased police checks, widespread use of mobile and fixed-speed cameras, and strict implementation of penalties (Bhalla et al., 2013). A different, but still valid indication that enforcement had impact was given in a special case: after an initial steady decline in speeding, a sharp increase was observed in the fall of 2013. This increase was likely associated with a change in enforcement regulation where tickets were not issued any more for vehicles exceeding the speed limit up to 20 km/h over the limit (Bhalla et al., 2013).

Final comment

The starting point for this article was that there were clear voices from global actors like the UN and WHO that speed is killing many people on the roads. The finding, however, is that these dramatic statements are not followed up. It is almost impossible to find any projects or programs, big or small, which takes its starting point in the fact that speed is one of the biggest – if not biggest − safety problem. Besides, there is reason to believe that there are many other positive side effects of lower speeds that is adding to the positive safety effect. It is about time that strategies are found that could translate the nice words presented globally into action. The basic problem is that scientifically valid results are rare.

However, what is clear is that authorities must stop using education and other campaigns as their main tools to reduce injuries and deaths on roads, and instead accept that other much stricter measures have to form the basis for any strategy. Most striking is the slow progress regarding speed limiters. It is self-evident that the ‘car regime’ does not prioritize this kind of restriction. Looking at the safety potential, and the positive results of speed limiter trials that have been carried out, politicians and decision makers have a big responsibility to follow them up. It is about time that ISA and speed limiters are embedded in serious research and development programmes, where independent actors are play the key roles. So far, the speed limiter is a theoretical concept for most drivers and other road users. It is particularly important to find out the ‘pure reactions and behaviours’ of drivers when they are faced with the new situation with speed limiters in their vehicles.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes

1 https://etsc.eu/1st-annual-road-safety-performance-index-pin-report/.

2 https://etsc.eu/in-vehicle-technology-vital-to-tackling-speeding-in-europe/.

3 https://www.youtube.com/watch?v=ScpgI1w5F6A

4 https://tsh.toi.no/index.html?22141

5 https://ec.europa.eu/transport/road_safety/specialist/knowledge/speed/speed_limits/education_and_publicity_campaigns_en

6 https://www.irap.org/

7 https://en.wikipedia.org/wiki/Speed_limiter

8 https://en.wikipedia.org/wiki/New_Car_Assessment_Program

9 https://www.euroncap.com/en/vehicle-safety/the-ratings-explained/safety-assist/speed-assistance/.

10 http://www.who.int/violence_injury_prevention/road_traffic/countrywork/en/