category: literaturenote citekey: schulzerolesafetyresearchroad2010 title: The role of safety research in road safety management authors: "Schulze, Horst; Koßmann, Ingo" year: 2010 date: 2010-00-00 2010 doi: 10.1016/j.ssci.2009.12.009 publication: Safety Science url: "https://doi.org/10.1016/j.ssci.2009.12.009" zotero_key: RAD3GMKI zotero_storage: VBIVXUGC collections: transpordi_planeerimine folder: 001_artiklid/Road Safety Indicators firstAuthor: "Schulze, Horst"

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Safety Science

journal homepage: www.elsevier.com/locate/ssci

The role of safety research in road safety management

Horst Schulze *, Ingo Koßmann

Federal Highway Research Institute (BASt), Brüderstraße 53, D-51427 Bergisch Gladbach, Germany

article info

Article history: Received 2 September 2009 Received in revised form 30 November 2009 Accepted 12 December 2009

Keywords: Road safety Safety management Safety research Accident Alcohol limit Road safety campaign

abstract

Mobility is a matter of great importance in daily life: However, it also causes costs and involves accident risks. To make mobility safer and reduce accident risks, a scientifically based road safety management is needed. Within such a safety management system, a concert of adequate and efficient strategies, tools and measures is developed and implemented. To ensure that the chosen means are efficient they should be derived from research evidence. Secondly, research is also needed to regularly monitor the impact of road safety management tools, serving as a ''controlling instrument" for the appropriateness of safety management efforts. This article explains the main strategic aspects of safety management in Germany and illustrates it exemplarily on the basis of two recently implemented road safety measures.

-2010 Elsevier Ltd. All rights reserved.

1. Introduction

Mobility is an essential element of any developed country or region. The challenge for Germany as a transit country in the centre of the European Union is not only to have a modern and broad network of transportation facilities, but also to operate it at a minimum of costs to obtain a maximum of welfare. Beside costs of investment and maintenance costs resulting from accidental injuries as well as related property damages have to be taken into account. In Germany, every year around 17.5 billion Euros are spent in the highway sector and road accidents cost the economy approximately 30 billion Euros per year.

During the last decades, road safety continuously improved from about 20,000 fatalities in the 1970s in West Germany to less than 4500 in 2008 in the reunified Germany. This positive development did not occur incidentally, but seems to be the result of the successful implementation of a multitude of road safety measures influencing road users' behaviour sustainably. As can be seen in Fig. 1, some measures can be directly linked to the development of the fatality numbers. After a fatality peak in the early 1970s, a speed limit on rural roads of 100 km/h was implemented in 1972 and led, together with the implementation of a blood alcohol concentration limit of 0.8‰, to the first remarkable decrease of fatalities. Further measures to be mentioned is the introduction of fines for not using a helmet as a motorised two-wheeler in 1980 and for not wearing a seatbelt as a front passenger in 1984 as well as the

Fig. 1 demonstrates that a strong linkage exist between realized safety measures and the positive development of fatalities. As can be seen in Fig. 2 this positive development cannot be explained by parameters as population development, the number of vehicles or vehicle mileages. But nevertheless without realizing evaluation studies these interrelations remain only presumptions.

These data underline the necessity of scientifically based road safety management strategies and tools to ensure road safety improvements. The aim of this article is to highlight the role of safety research in road safety management and to describe the scientifically based management tools established in Germany serving to

explain reasons of safety deficits,
define and recommend evidence based measures,
assess the safety impact of an implemented single measure and
continuously control in how far the objectives of the national road safety action plan are met.

The description of two recently implemented road safety measures will give an example how these tools concretely are applied.

2. Road safety research in Germany

The stronger road safety policies are science-based, the more efficient they will be in reducing fatalities and the severity of road accidents. This asks for an appropriate support of policy makers by road safety research.

reduction of the blood alcohol concentration limit from 0.8‰ to 0.5‰ in 1998.

^* Corresponding author. Tel.: +49 2204 43400; fax: +49 2204 43403. E-mail address: Schulze@bast.de (H. Schulze).

Fig. 1. Fatalities in road traffic and safety measures.

Fig. 2. Development of fatalities in road traffic by population, vehicle stock and mileages.

In Germany, the Federal Highway Research Institute (BASt) has the task to meet this challenge and to give scientifically sound support on all issues and questions of traffic policy to the Federal Ministry of Transport, Building and Urban Affairs (BMVBS) as well as drawing up and harmonization of technical standards on a national and European level. BASt's overall objectives are the improvement of safety, the economical and operational efficiency and the environmental soundness of roads. Scientific work of the approximately 400 employees of the institute accounts for over 75% of all work carried out. BASt activities range from own and funded research over certifications and accreditations to the elaboration of expert reports and advising. About 350 own research projects and more than 300 supervised projects carried out by external scientists are carried out per year. Approximately 500 scientific statements are realized for the Federal Ministry of Transport and a further 500 for third parties annually. Besides that, BASt is involved in 550 national and international bodies and associations in the field of road transport.

In 1951, BASt began its research work in the field of highway construction. In 1965, the institute was commissioned, beyond the scope of highway construction tasks, to work towards highway capacity and safety. With economic growth after World War II, passenger and goods transport increased. However, with technical improvement and increasing potential of individual mobility also accident numbers were rising. In 1953, the official road traffic accident statistic was implemented. Since then, a more or less straight increase of fatalities was recorded with a climax in 1970 with nearly 20,000 fatalities only in the western part of Germany. In reaction to this development the Federal Parliament voted to establish a central agency for road traffic accident research which was set up at BASt in 1969.

Since the 1970s road safety research and road safety policy show a successful path over the following years as the number of fatalities has continuously decreased and reached the all-time low in 2008 with about 4500 fatalities. The break at the end of the 1980s marks the German reunification and since then the accident statistics contain both former parts of Germany. Before 1990, only the former western part is pictured in the graph (Fig. 1).

After two decades of rising accident numbers and due to the peak of fatal accidents, the first national road safety programme was established in 1973 and a second was published in 1984. The latest agenda for road safety activities in Germany was introduced in the year 2001 with the German ''Programme for Improving Road Safety". This programme was developed in co-operation with BASt and the Federal Ministry of Transport, Building and Urban Affaires.

The goal set in this programme was ''to secure mobility and road safety for all users" which means to face the task of making mobility as safe, as environmentally friendly and as socially fair as possible. Targeted actions of the programme refer to road user behaviour, safe vehicles and telematics, safe transport infrastructure and effective emergency services.

Within the programme five priorities are given:

improving road safety culture,
protecting weaker and vulnerable road users,
reducing accident risks of young drivers,
lowering the risk potential of heavy goods vehicles and
enhancing safety on rural roads.

The ''Programme for Improving Road Safety" provides the basis for all further road safety actions.

To support the objectives of this strategic programme, different road safety research programmes exist in Germany defining concrete research tasks to improve road safety.

The so-called Safety Research Programme is directly dedicated to road traffic safety and thus the central programme for road safety research. The programme refers to safety deficits in traffic either already known or to be expected. Thus, the purpose of this research programme is to consult and support the Federal Ministry of Transport, Building and Urban Affairs (BMVBS) on a scientific, research-based basis. It is annually developed within BASt by an interdisciplinary workgroup involving different departments and regularly contains about 10–15 projects a year. The questions stated in the safety research programme are basically orientated to the road safety programme of the Ministry.

A further research programme is the Road Research Programme of the German Ministry of Transport, Building and Urban Affairs. This programme contains so-called resort-projects and joint projects of the Federal Ministry of Transport, Building and Urban Affaires and the German Research Association for Roads and Road Traffic (FGSV). Research projects in this programme concentrate mainly on aspects of traffic engineering and traffic construction. A third programme, the Research Programme for Urban Traffic of the Federal Ministry of Transport, Building and Urban Affaires, deals only with research activities of urban traffic problems. Traffic safety aspects play only a minor role in this programme. Finally, the Innovation Programme is also in responsibility of the German Ministry of Transport, Building and Urban Affairs and still in the phase of implementation. The aim of this programme is to promote new concepts and technologies mainly in the field of road and infrastructure construction.

Research fields in road safety research refer to road users, vehicles and infrastructure. Sometimes research affects these fields separately, but in most of the cases research work has to be done interdisciplinary. Facing the challenge to develop efficient measures for improving road safety – especially when public resources are scarce and economic means are limited, BASt's road safety research duty is to enhance knowledge and to create effective and efficient road safety measures as well as to offer a continuous development of the whole road safety network. The tasks of BASt are distributed among the administrative service department and five specialised departments:

Behaviour and safety.
Automotive engineering (and to cover the infrastructure).
Traffic engineering.
Highway construction technology.
Bridges and structural technology.

Based on this organisational differentiation, the Safety Research Programme is divided into the main topics

Basis data.
Human beings in traffic.
Vehicle technology.
Road traffic technology.

2.1. Research topic ''Basis data"

The determination of the main topics for road safety activities, the development of measures and the early recognition of new developments are based on information regarding the current road safety situation and basic traffic conditions. Against this background the use of seat belts and child restraint systems in motor vehicles as well as the use of helmets and protective clothing on two-wheelers are, for example, continually ascertained since 1975. The ''investigations at the scene of the accident", carried out by the University of Hannover since 1973 on the initiative of BASt, enable to gather detailed accident data which form an essential data basis for research questions concerning passive and active vehicle safety. This data basis has been extended by a co-operation between the BASt and the Research Association of Automotive Technology.

2.2. Research topic ''human beings in traffic"

Human beings are, of course, the central key actors in traffic. Depending on the age of the road user, the means of transport being used, but also the readiness to take risks, road users' traffic safety differs considerably. Therefore BASt has continuously dedicated its safety research to human factors. In order to reduce the high accident risk of novice drivers, for example, the measure ''Accompanied Driving from 17 years" has been elaborated an implemented, up to now on a model basis.

2.3. Research topic ''vehicle technology"

Vehicle technology plays an important role for the increase in road safety. In the field of passive vehicle safety, considerable technological improvements based on research lead to a significant increase of road safety in the past years – especially reduced numbers of fatal accidents. The task remains to make use of the existing reduction potentials of passive vehicle safety and at the same time to deal with the high potential of measures for active vehicle safety.

2.4. Research topic ''road Infrastructure"

Highway design and highway equipment have a great influence on the road safety. The more complex the road system becomes, the more human errors are likely to happen. A road infrastructure that is adapted to the safety requirements can thus considerably reduce the frequency and seriousness of accidents. Within the framework of the safety research, for example, improvements of passive protective devices such as safety barriers have been elaborated to reduce the number of accident consequences particularly for motorcyclists. However, research projects regarding aspects of road design (for example the design of road junctions) which lead to a sustainable improvement of road safety have also been conducted.

Finally, at the beginning of the 1970s the German Parliament also requested the Federal Government to regularly present a report on the development of road accidents and countermeasures. This so-called accident prevention report is provided by BASt and reports on the realisation of road safety measures announced in the Road Safety Programme. The report is orientated to the priorities of the Road Safety Programme and is primarily used to compare steps that have been planned to those that have been realized in order to arrange adjustments if necessary.

The accident prevention report illustrates the development of traffic safety in Germany, shows the road safety policies and decisions in the relevant time period and gives an overview of corresponding topics on an international level. The report retrospectively shows the road safety measures that have been started or already been concluded and prospectively gives a preview of further steps that have to be taken to realise certain measures and future measures. Thus, the Accident Prevention Report has the function of a controlling instrument to improve road safety.

3. Examples of recent road safety measures in Germany

In spite of continuous improvements in road infrastructure being more and more adapted to the limitations of human capacity, in active and passive safety of vehicles, simplifying the driving task to decrease the crashworthiness and in emergency medical systems to reduce the consequences of injury, the human factor is still a major source of risk. Therefore road users should be adequately educated and informed about key safety behaviour and deterred and restricted in order to counteract unsafe behaviour patterns.

In this context speeding and alcohol impaired driving have to be mentioned as major topics of road safety management, asking for scientifically based countermeasures. In the following the behavioral scientific contribution to the road safety policy consulting will be described by means of two current measures.

3.1. Introduction of the zero alcohol limit for young drivers

In August 2007, Germany introduced the zero alcohol limit for young drivers. This rule is related to novice drivers during the two years probationary period and/or individuals younger than 21. For the defined target group it is forbidden to drive under any influence of alcohol. The first violation of this regulation is fined with 125 € and two demerit points. Violations during the 2 years probation period lead to a prolongation of the probation period for another 2 years and the participation in special driver improvement courses might be mandated. The legitimation of this enactment was drawn from empirical findings on accident risk, psychological explanations of risk taking behaviour and available evaluation studies (Voas et al., 2003).

3.1.1. Accident statistic

During the last decades the proportion of alcohol related accidents continuously decreased. Nevertheless alcohol is still a very important cause for fatal accidents, especially for novice drivers. In 2007 18–24 years old drivers were responsible for one third of all alcohol related fatalities on German roads (Federal Statistical Office, 2007).

3.1.2. Risk factors

The exceptionally high accident risk of young drivers is the result of the interaction of a multitude of unfavourable factors. The developmental process of important cognitive skills like strategies of perception, alertness strategies, automatisms and the handling of motor vehicles is still not finalized. Alcohol boosts the specific problems and deficits of novice drivers. The risk increasing properties of alcohol hold for all novice drivers independent of their age. As young drivers compared to other age groups are more often driving during night time they are much more exposed to drink driving conflicts. 50% of their drinking episodes take place during night time, at weekends and outside of their homes (Krü ger, 1995).

3.1.3. The relative risk of novice drivers

Already small blood alcohol concentrations may severely influence the driving ability of young inexperienced drivers. The results of the FARS 1987–1999 study (N = 192.282) in Fig. 3 prove that the relative accident risk of 16–20 years old drivers with a BAC of 0.1‰ is already 32% higher than for drivers with a BAC of 0.0‰ (Preusser, 2002). Similarly, the results of a German study on the relative risk of alcohol in accident causation carried out by Krüger (1995) show that a BAC of 0.3‰ in the age group of 18–24 years old drivers increase the risk to cause an accident by 44%. Zador et al. (2000), analyzing 2.135 single accidents of male drivers of the year 1996 in the USA, found that young drivers' risk to be fatally injured in a road accident increases by 55% with a BAC of 0.1–0.19‰. For young female drivers of this age group the respective increase was 35%. Further evidence of the low-BAC effect on young drivers is shown by Keall et al. (2004).

Fig. 3. Crash risk by age and BAC, reference group: driver ages 35–45 at 00% BAC (Preusser, 2002).

3.1.4. Results of evaluation and acceptance studies

The introduction of alcohol bans in the USA and Canada lead to decreases of fatal accidents between 11% and 33% (Kedjidjian, 1993; Hingson et al., 1994; Mann, 1997; Zwerling and Jones, 1999; Wagenaar et al., 2001).

From Austria, where a 0.1‰ BAC limit was introduced in combination with a probationary license, a reduction of the proportion of alcohol impaired novice drivers (BAC > 0.8‰) being involved in severe accidents decreased by 17% (Bartl and Sturmvoll, 2000).

Three representative public opinion polls, carried out in 2007 in Germany independently from each other, found that the acceptance of the planned tightening of the alcohol legislation for novice drivers was very high in the general population (87%) as well as in the age group of 18–24 years old (82–92%).

As demonstrated, the implementation of the zero alcohol limit for novice drivers strictly followed the state-of-the-art of empirical knowledge of road safety research in this field. The cost-benefit relation of this measure was classified to be quite positive. It was expected that this measure in short-term will lead to a decrease of young drivers alcohol related accidents as well as to a decrease of driving under the influence of combined use of alcohol and illicit drugs. In long-term it is expected that alcohol related accidents will decrease in general as the individual alcohol consumption patterns in terms of consumption frequency and quantity are developed between 16 and 24.

The question in how far these expectations will be fulfilled is the objective of an ongoing evaluation study carried out by BASt. The evaluation study focuses on the analysis of data of the Federal Accident Statistic and the Central Register of Traffic Offenders, a representative opinion poll on attitudes and behaviour (changes) in the target group and the investigation of the practical surveillance of the zero alcohol limit by the police. Although this study is not yet finalised, the results of the Federal Accident Statistic of 2008 give rise to optimism as there was a decrease of the accident cause ''alcohol" by 11% in the age group from 18 to 21 years whereas the decrease of this accident cause was only 6% over all age groups.

3.2. Development of national road safety campaigns

In the field of road safety campaigns the role of BASt is the scientific support of the Federal Ministry of Transport, Building and Urban Affaires within all relevant decisions that have to be taken. This concerns the definition of aims, target groups, central messages, design and implementation of campaigns as well as the initialisation and supervision of evaluation studies carried out by external contractors.

How the main steps of this scientific consulting process are carried might be most easily demonstrated by citing the ongoing campaign ''Runter vom Gas!", whose objective is to raise road users awareness of ''unadjusted speed" being the major cause of fatal accidents on German roads. This national campaign initiated by the Federal Ministry of Transport, Building and Urban Affairs runs from March 2008 to October 2009. Within a broad communication structure different thematically topics, actions and events should be presented by using various media (e.g. billpostings on motorways, newspaper and magazine adds, cinema/television and radio spots, websites) to address the message to a broad audience.

The road safety related scientific contribution comprised the following issues (Gelau and Pfafferott, 2009; Delhomme et al., 2009).

3.2.1. Aim and message of the campaign

''Unadjusted speed" was defined as the main topic of the campaign. The aim is to sensitize drivers to the danger of speeding and to draw public awareness to the topic of speed as the main risk factor for accident causation ''Agenda Setting"). The implementation process of the campaign was strictly based on the empirical knowledge derived from prior studies on the psychological impact of unadjusted speed.

3.2.2. Target groups

Basically the campaign addresses everybody driving with unadjusted speed. However, as accident research shows, the heterogeneous group drivers can be divided into various homogeneous subgroups differing in their risk of being involved in road accidents. Therefore two special campaign series focused on young drivers and motorcyclists. In this task the Federal Ministry of Transport, Building and Urban Affaires as well as the responsible PR agency were supported by BASt providing the scientific knowledge about these two risk groups.

3.2.3. Communication strategy

Confronting the target group with threatening messages (fear arousal communication) was recommended by BASt as a suitable strategy to change speed related attitudes and behaviour. Such a strategy should be preferred if arguments alone are not expected to have any effect on attitude or behaviour. Fear appeal is expected

Fig. 4. Motive of the German road safety campaign ''Slow down!".

to evoke emotional reactions promoting safety oriented thinking (Holte, 2005; Green and Witte, 2006). There is evidence from research, that fear arousal communication can be successfully implemented in road safety campaigns, if the audience gets additional information about possible solutions to reduce the accident risk (e.g. Shanahan et al., 2000). The solution offered in the campaign is expressed by the slogan ''Runter vom Gas!" meaning ''Slow down!". The motives of the first campaign season were composed as fictive obituaries. They show photos of happy families, couples or friends next to a huge black cross. It is mentioned that these people died in a road accident for example because they drove too fast on a wet road (see Fig. 4).

3.2.4. Evaluation of the road safety campaign

Two evaluation studies were planned to reveal in how far the targets of the campaign were reached and to derive recommendations how the campaign should be continued. As it is important to ensure that the design of the studies, the analysis of data and the interpretation of the results are fully in line with scientific standards, BASt supervised these studies performed by an external contractor. The results of the first evaluation study show a very good media coverage in terms of road safety related commentatorship, a remarkable awareness level (61%), and they confirm that the chosen fear arousal communication approach was perceived in general as appropriate to transport the chosen message without age, gender or traffic mode related differences (Klimmt and Maurer, 2009).

Conclusions drawn from the results of the evaluation study for the continuation of the campaign were to retain fear arousal communication with escalation of the shock dosage, additional focusing of online communication, continuation of the scientific evaluation and deepening concomitant research (e.g. information processing of campaign related messages).

4. Conclusion

It has been outlined how a scientifically based safety management system, comprising strategic elements, tools and measures, is applied in Germany. Such a safety management system includes a political programme containing important fields of action to improve road safety, a scientific research programme targeting the safety issues raised in the political road safety programme and – based on research results – the development and implementation of adequate road safety measures. The efficiency of these measures again is scientifically monitored.

Looking at the history of road safety in Germany in the past decades it was shown that the realisation of several road safety measures seems to be responsible for the considerable reduction of the number of fatalities since the beginning of the 1970s when fatality rates reached their peak with about 20,000 people killed in traffic in West Germany. Due to missing evaluation studies the linkage between realized measures and the reduction in fatalities remain only presumptions. As a consequence, need for scientifically based road safety management strategies and tools to ensure further road safety improvements was identified and a safety management tool was developed and implemented. Nowadays in spite of tripling the number of vehicles and vehicle mileages in 2008 in contrast to 1970 a new lowest level with about 4500 fatalities could be reached by a continuous safety management and effective countermeasures targeting on safe behaviour of road user as well as on technological and infrastructural development and improvement.

However, the decrease in fatalities seems to be associated with an increase in the number of most seriously injured persons, so that in future this topic will be central. Furthermore, the demographic change, the decrease in population and the increasing disproportional regional distribution will cause a change in the future Germany. The percentage of elder persons is expected to increase considerably within the next years so that questions concerning road safety with regard to this population group will become more central in the future. In addition to that, electronic systems enabling motor vehicles to communicate with each other or with infrastructure will gain further importance for the improvement of road safety. These mentioned topics of future challenges will determine road safety management and research for the next years.

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