Scholarly article on topic 'Characteristics and Causes of Power Two Wheeler Accidents in Europe'

Characteristics and Causes of Power Two Wheeler Accidents in Europe Academic research paper on "Civil engineering"

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Abstract of research paper on Civil engineering, author of scientific article — George Yannis, Constantinos Antoniou, Petros Evgenikos, Panagiotis Papantoniou, Alan Kirk

Abstract Powered two wheelers (PTW) are very popular modes of transport, with dominant modal share in some developing countries, but also throughout the world. More than 62.000 persons were killed in traffic accidents involving PTWs in the 27 European Union countries between 2001 and 2009. In these 27 countries there were -18% fewer PTW traffic accident fatalities in 2009 than in 2001 in comparison to -36% fewer fatalities in total. The objective of this research is the analysis of PTW road safety related parameters in European countries through the use of the EU CARE database with disaggregated data on road accidents as well as of other international data sources (OECD/IRTAD, Eurostat, etc.). Time-series data from 23 EU countries over a period of 10 years (1999-2008) are correlated with basic safety parameters, such as area type and age and gender of the driver. Additional insight into accident causation is offered through the use of in-depth accident data from the EC SafetyNet project Accident Causation Database. The results of the analysis allow for an overall assessment of the PTW road safety level in Europe in comparison to other modes, thus providing useful support to decision makers working for the improvement of safety in the European road network.

Academic research paper on topic "Characteristics and Causes of Power Two Wheeler Accidents in Europe"

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Social and Behavioral Sciences

Procedía - Social and Behavioral Sciences 48 (2012) 1535 - 1544

Transport Research Arena - Europe 2012

Characteristics and causes of power two wheeler accidents

in Europe

George Yannisa'*? Constantinos Antonioub, Petros Evgenikosc, Panagiotis Papantonioud9 Alan Kirke

aAssociate Professor, Iroon Polytecheiou 5, Athens, 15773, Greece bAssistant Professor, Iroon Polytecheiou 9, Athens, 15780, Greece cResearch Associate, Iroon Polytecheiou 5, Athens, 15773, Greece dPhD Candidate, Iroon Polytecheiou 5, Athens, 15773, Greece eResearch Fellow, Design School, Loughborough University, Leicestershire, LEU 3TU, UK

Abstract

Powered two wheelers (PTW) are very popular modes of transport, with dominant modal share in some developing countries, but also throughout the world. More than 62.000 persons were killed in traffic accidents involving PTWs in the 27 European Union countries between 2001 and 2009. In these 27 countries there were -18% fewer PTW traffic accident fatalities in 2009 than in 2001 in comparison to -36% fewer fatalities in total. The objective of this research is the analysis of PTW road safety related parameters in European countries through the use of the EU CARE database with disaggregated data on road accidents as well as of other international data sources (OECD/IRTAD, Eurostat, etc.). Time-series data from 23 EU countries over a period of 10 years (1999-2008) are correlated with basic safety parameters, such as area type and age and gender of the driver. Additional insight into accident causation is offered through the use of in-depth accident data from the EC SafetyNet project Accident Causation Database. The results of the analysis allow for an overall assessment of the PTW road safety level in Europe in comparison to other modes, thus providing useful support to decision makers working for the improvement of safety in the European road network.

©22012 Published by Elsevier Ltd. Selection and/or peer review under responsibility of the Programme Committee of the Transport Research Arena 2012

Keywords: powered two wheelers; road accident data; road safety; European countries

ELSEVIER

* Corresponding author. Tel.: +30 210 7721326; fax: +30 210 7721454. E-mail address: geyannis@central.ntua.gr

1877-0428 © 2012 Published by Elsevier Ltd. Selection and/or peer review under responsibility of the Programme Committee of the Transport Research Arena 2012

doi:10.1016/j.sbspro.2012.06.1129

1. Introduction

Powered two wheelers (PTW) are very popular modes of transport, with dominant modal share in some developing countries, but also throughout the world (Solere, 2010; Musso and Corazza, 2010). As a matter of fact, the number of PTWs is increasing, strengthening the expectation that motorcycles can play an important role in the transport strategy in major cities (Livett, 2007). Moped and scooter use is also increasing, to a large degree due to the economy, practicality, time-efficiency and enjoyment of riding (Blackman and Haworth, 2010). However, PTW riders often behave differently than car drivers, particularly relating to their speeding behavior (Broughton et al., 2009). Furthermore, the maneuverability of the vehicle is also a significant expressive parameter of the PTW riders. This type of behavior is more often seen with adolescent riders (Nja and Nesvag, 2007). Overall, the special characteristics of PTWs put them in a very special (disadvantageous) situation in the road safety landscape, as they combine a unique flexibility and expressiveness with a vulnerability that makes their riders' chances of being severely injured in a crash much higher than those of other road users.

The objective of this research is to present a macroscopic analysis of road safety for PTWs using data from the EU CARE database with disaggregated data on road accidents, together with data from other international data files (e.g. IRTAD, as well as national sources). In particular, road accident data on PTWs from 23 European (EU) countries for the decade 1999-2008 are correlated with basic safety parameters like the socioeconomic characteristics of the riders. Infrastructure factors have not been studied in detail in this paper. Additional insight into accident causation is offered through analysis of a set of in-depth data, collected using a common methodology for samples of accidents that occurred in Germany, Italy, The Netherlands, Finland, Sweden and the UK. The data, on which this analysis is based, along with much of the analysis and the way that the different types of databases were combined, is obtained through the SAFETYNET and DaCoTA EC co-funded research projects and the European Road Safety Observatory (ERSO).

The remainder of the paper is structured as follows. Background and related work are outlined in the following section, followed by a presentation of the overall evolution of PTW fatalities over the considered period of 10 years. In the following sections, socioeconomic characteristics (age and gender) and road network characteristics are correlated with moped and motorcycle fatalities. A section providing insight on PTW accident causation based on the analysis of in-depth data follows and a concluding section integrates the main observations. An appendix lists the country abbreviations used throughout this paper.

2. Background and related work

It is useful to consider the various definitions and regulations for motorcycles and mopeds in the various European Union member states. In most EU countries a moped is defined as a PTW with an engine size below 50cc and design speed up to 50 km/h, prohibited on motorways. The minimum age for the rider varies between 14 and 16 years old. The use of a helmet is required in most countries, while a compulsory theoretical test is often required and in most countries a practical test is also required. A license plate and vehicle register is being introduced to more and more countries. A motorcycle is a PTW with an engine size above 50cc, allowed on motorways. A driving license is compulsory. The minimum age allowed is between 16 and 18 years old for engine sizes up to 125cc or power up to llkW Larger engine sizes are allowed after 2 years of experience. A helmet is required. Scooters should be assigned to one of the categories depending on their engine size.

Licensing is a big issue with PTWs. In Europe there are approximately 300 million licenses and the EU has established (new) EU directives (see ec.europa.eu/transport/home/drivinglicence/index_en.htm) aiming at the harmonization of licenses across countries. The main aims of this proposal are the (i)

reduction of fraud, (ii) guarantee of free movement of citizens across member states and (iii) contribution to improved road safety (European Commission, 2003).

Age, gender and experience are among the parameters that considerably affect the riders' behavior. A recent, thorough review of the topic is presented by the 2BESAFE (2010) project. Yannis et al. (2005) calculate accident severity and relative fault risk rates using data from the national accident database of Greece and study the combined effect of driver age and engine size on accident severity and at-fault risk of young riders of two-wheelers. Limited experience and poor driving skills due to a loose motorcycle licensing system are critical for young riders, particularly young female riders in increasing accident risk (Chang and Yeh, 2007). Males from 10 to 19 years of age had the highest risk of injuries following accidents with mopeds. For accidents with motorcycles, the highest risk was found in the age group of 20 to 29 years (Barsi et al., 2002).

Road infrastructure is also an important factor related to PTW accidents. Montella et al. (2011) present a statistical exploratory analysis of a large number of PTW accidents in Italy and find that PTW crashes are strongly sensitive to several road, environment, and rider attributes. De Rome and Senserrick (2011) performed an exploratory analysis of PTW accidents in New South Wales, Australia, and concluded that while PTW crash rates showed an encouraging decline, countermeasures are needed to protect the increasing numbers of riders. The analysis also highlighted the need to focus on specific high-risk crash types (head-on, rear-end and intersection crashes) and target them in education and training campaigns for PTW riders. Yannis et al. (2010) present an analysis of road infrastructure and safety of PTW using data from the European Union.

3. Overall trends

More than 62.000 persons were killed in traffic accidents involving motorcycles and mopeds, together referred to as Powered Two Wheelers (PTWs), in the 27 European Union countries between 2001 and 2009. In these 27 countries there were -18% fewer PTW traffic accident fatalities in 2009 than in 2001 in comparison to -36% fewer fatalities in total (ETSC, 2011). PTW fatalities accounted for 17,7% of the total number of road accident fatalities in 2008 in the EU-23 countries.

In 2008, 1.213 riders (drivers and passengers) of mopeds were killed in the EU-16 in traffic accidents, 7,8% less than the number in 2007 in the same countries. The annual total decreased by 47% during the decade for these countries, an average of 6,6% per year.

In 2008, 3.999 riders (drivers and passengers) of motorcycles were killed in the EU-16 countries in traffic accidents, 10,3% less than the number reported in 2007 for the same countries. However, the annual total increased for these countries by 7,2% during the decade, an average of 0,9% a year.

As there is no reliable data available about the exposure of PTWs (vehicle kilometres or fleet numbers) in each of the above countries, it is difficult to interpret the numbers of fatalities in the group of PTW or the difference in the distribution over mopeds and motorcycles. In some countries, like Greece and Czech Republic, the majority of PTW fatalities are motorcyclists, while in Ireland and the United Kingdom there are hardly any moped fatalities.

The number of PTW fatalities as a proportion of the national fatality total varied in the EU-23 countries (complete list presented in the appendix at the end paper) from 5,3% (EE) to 29,2% (IT) in 2008, while the average for the EU-16 was 20,4% and for the EU-23 17,7%. Figure 1 indicates that between 1999 and 2008 the fatality rate of PTW declined in most of the EU-16 countries. The most significant reduction occurred in Portugal (32,3%), whereas the fatality rate increased in the Czech Republic, Denmark, Italy, Luxembourg, Romania, Finland and Sweden.

Figure 2 shows that the trend for motorcycle user fatalities differs clearly from the trend for other modes of transport. Motorcycle is the only mode of transport for which the number of fatalities has

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increased over the period studied. This observation underlines the urgency of taking immediate appropriate counter measures.

Figure 1. Motorcycle and moped rider fatalities per million inhabitants (1999 vs. 2008). Source: CARE Database / EC, Date of query: November 2010

Figure 2. Index (1999=100) of motorcycle and moped fatalities compared with other modes EU-16, 1999-2008, Source: CARE Database / EC, Date of query: November 2010

4. Socioeconomic characteristics

In this section, the relation of age and gender of PTW riders with fatalities is analyzed. In 2008, almost 25% of motorcycle and moped rider fatalities were younger than 25 years old. It is noted that the age at which driving a moped or motorcycle is allowed varies across the European Community. A large majority of the PTW fatalities were male in all countries. 10% of moped fatalities were females, and 6,5% of motorcycle riders. The number of moped (left subfigure) and motorcycle (right subfigure) rider fatalities

by single year of age is presented in Figure 3. The insets express the numbers in 2008 relative to the numbers in 1999 (the numbers have been averaged over the age one year before and after in order to smooth the age dependency). The inset in the top subfigure shows that the number of moped rider fatalities fell between 1999 and 2008 for almost all ages. Some observations that can be drawn from these figures include that almost 40% of the moped rider fatalities are aged between 15 and 24 years old in 2008 and that the number of motorcycle rider fatalities aged 40-60 year old doubled between 1999 and 2008. The number of motorcycle rider fatalities fell between 1999 and 2008 only for those under the age of 30, while it rose for most ages over 30.

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■Motorcycle 2008 —Motorcycle 1999

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10 20 30 40 50 60 70 80 90 Age

10 20 30 40 50 60 70 80 90

Figure 3. Moped (left) and motorcycle (right) fatalities by age in 1999 and 2008 (for EU-16). Source: CARE Database I EC, Date of query: November 2010

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Figure 4. Motorcycle and moped fatalities per million inhabitants by age group - EU-23, 2008 Source: CARE Database I EC, Date of query: November 2010

Figure 4 shows the fatality rate by age group in the EU-23 countries. It can be seen that the rates for moped riders aged 15-19 and motorcycle riders aged 20-29 are particularly high. Interesting conclusions can also be drawn from an analysis of the PTW fatalities, with respect to whether they were riders or passengers. Almost all fatalities among PTW users were riders (in control), only 6,4% were passengers, while 69% of female moped fatalities were riders. On the other hand, 54% of female motorcycle fatalities were passengers.

5. Road network

The majority of PTW fatalities in all countries occur on non-motorway road network. In the case of mopeds, this can be justified by the fact that mopeds are not allowed on motorways in most European countries. The existence of medians, separating opposite traffic flows on motorways, also contributes to a reduction in the number of fatal PTW accidents. The majority of moped fatalities occur in urban areas whereas the majority of motorcycle fatalities occur in rural areas. Figure 5 shows that in 2008, 42% of the motorcycle rider fatalities and 58% of the moped rider fatalities were killed inside urban areas. These proportions are considerably larger than the respective figures for car occupants (23%). In 2008, relatively few motorcycle rider fatalities occurred on motorways (5%), compared to car occupant fatalities (7%).

Figure 5. The distribution of PTW fatalities by area and road type, 2008 Source: CARE Database / EC, Date of query: November 2010

Figure 6. Fatalities by junction type and mode of transport - EU-23, 2008 Source: CARE Database / EC, Date of query: November 2010

Figure 6 indicates that almost a third of all motorcycle and moped rider fatalities occur at a junction (28,6%). The respective figure for car occupant fatalities occurring at a junction is only 14%. Furthermore, it is noted that nearly 50% of the overall motorcycle/moped rider fatalities recorded at a junction occurred at crossroads. Also, the highest proportion of fatalities atjunctions is found for bicycles and powered two-wheelers.

6. Accident causation analysis

Additional insight into accident causation can be offered by in-depth data, such as those collected during the EU co-funded SafetyNet project. During that project, in-depth data were collected using a common methodology for samples of accidents that occurred in Germany, Italy, The Netherlands, Finland, Sweden and the UK (Bjorkman et al., 2008; Reed and Morris, 2008). The SafetyNet Accident

Causation Database was formed between 2005 and 2008, and contains details of 1.006 accidents covering all injury severities. A detailed process for recording causation (SafetyNet Accident Causation System -SNACS) attributes one specific critical event to each driver, rider or pedestrian. Links then form chains between the critical event and the causes that led to it. For example, the critical event of late action could be linked to the cause observation missed, which was a consequence of fatigue, itself a consequence of an extensive driving spell. Links are established by trained personnel directly involved in the investigation according to the SNACS coding system, with full case evidence available to them. In the database, 17% of the accidents involve the rider of a PTW. Males account for 83% of this group and the mean age is 32 years old. Figure 7 (a) compares the distributions of specific critical events for PTW riders and other drivers or riders in PTW accidents.

Surplus speed

Premature action (initiated too early)

Late action

> Incorrect direction

(includes leaving road)

s Surplus force

Ô (excess acceleration or braking)

it= Shortened distance

& (road user(s)/environment too close) a.

w Prolonged action/movement

(continued on too long) Prolonged distance (action/movementtaken too far)

Insufficient speed

■ PTW riders n=177

■ other drivers/riders in PTW accidents n=140

15% 20% 25% 30% Proportion of drivers/riders

Links between causes Frequency

Others 63

Observation missed - Faulty diagnosis 5

Insufficient knowledge - Inadequate training 5

Faulty diagnosis - Communication failure 8

Inadequate plan - Psychological stress 8

Observation missed - Inattention 12

Observation missed - Inadequate plan 13

Observation missed - Permanent obstruction to view 16

Observation missed - Temporary obstruction to view 16

Inadequate plan - Insufficient knowledge 24

Faulty diagnosis - Information failure (driver/environment or driver/vehicle) 26

Figure 7. (a) Distribution of specific critical events - PTW riders and other drivers/riders in PTW accidents (left); (b) Ten most frequent links between causes - PTW riders (right) Source: SafetyNet Accident Causation Database I Date of query: Nov. 2010

The most frequently recorded specific critical event for PTW riders is surplus speed, very much in contrast to other drivers/riders in PTW accidents. Surplus speed describes speed that is too high for the conditions or maneuver being carried out, travelling above the speed limit and also if the rider is travelling at a speed unexpected by other road users. It is recognised that the PTW riders here are in a mix of single vehicle and multiple vehicle accidents, whilst the other drivers/riders are, by selection, in multiple vehicle accidents. Single vehicle accidents will be reflected in higher representations of surplus speed and incorrect direction (as it includes leaving the road). In a separate study, Haworth et al. (2009) found that risk taking, in terms of alcohol involvement and excessive speed, was more common in single than multi-vehicle accidents, while there were few differences in risk taking behaviors between moped and motorcycle riders. Broughton and Stradling (2005) discuss the reasons that people ride PTWs and identify a high level goal (enjoyment) and various lower level goals. The events under the general category of 'timing', no action, premature action and late action, account for the next three most frequent events after surplus speed. Premature action (one undertaken before a signal has been given or the required conditions are established, for example entering a junction too early) is recorded far more often for the other drivers/riders in PTW accidents than for the PTW riders.

Figure 7 (b) gives the most frequent links between causes in the chains recorded for PTW riders. For this group there are 196 such links in total. How often causes appear in the chains indicates their importance for the road users selected. Here only the most common links are presented but further

interpretation can take place by following the chains from critical event back to the first cause in the chain, as demonstrated by Talbot et al. (2009) for inattention and distraction.

For PTW riders, faulty diagnosis, inadequate plan and observation missed are frequently recorded causes. Faulty diagnosis is an incorrect or incomplete understanding of road conditions or another road user's actions. It is linked to both information failure (for example, a rider thinking another vehicle was moving when it was in fact stopped and colliding with it) and communication failure (for example, pulling out in the continuing path of a driver who has indicated for a turn too early). The main cause leading to inadequate plan (a lack of all the required details or that the driver's ideas do not correspond to reality) is lack of knowledge (for example, not understanding a complex junction layout), followed by psychological stress. The causes leading to observation missed can be seen to fall into two groups, physical 'obstruction to view' type causes (for example, parked cars at ajunction) and human factors (for example, not observing a red light due to distraction or inattention).

7. Conclusion and discussion

Powered two wheelers are a special group of road users, with increasing numbers and different needs and characteristics than other road users. During the last decade (1999-2008) the number of motorcycle rider fatalities (in EU-16) has increased by 7,2% (the only mode of transport in which there was an increase; on the other hand, it should not be overseen that the corresponding number of moped fatalities has decreased by 47%). In 2008, riders of PTWs made up 17,7% of the total road accident fatalities in EU-23. PTW rider fatalities are in general younger than other modes (almost 25% of the PTW rider fatalities were younger than 25 years old, while almost 40% of the moped rider fatalities in 2008 were aged between 15 and 25 years old). Changing demographics have also other implications. For example, the number of motorcycle rider fatalities aged 40-60 year old doubled between 1999 and 2008.

These observations, along with the other findings presented in this paper, could be used to shape public policy in a way that it improves road safety across the board and especially for the more vulnerable road users. The need to act is underlined by the evolution of the PTW rider demographics. Haworth and Nielson (2008) present the results of an analysis of PTW accidents in Australia from which they conclude that "while moped crashes comprised only a small fraction of on-road crashes of powered two-wheelers in 2001-05, they are increasing at a faster rate than motorcycle crashes". Furthermore, considering that mopeds are driven primarily by younger drivers and that the severity of accidents between mopeds and motorcycles was similar, further analysis should be performed to analyze the ways that moped crashes could affect the younger population. Furthermore, like all other vehicles, PTWs are starting to be equipped with Advanced Driver Assistance Systems (ADAS) and other safety equipment (such as speed alert or upcoming curve warning), which often feature an interface or interaction with the rider. The impact of such equipment on the driving task and distraction of the rider or driver is being investigated as it can have considerable impact on road safety (Bekiaris et al., 2009; Pieve et al., 2009).

The results of the analysis allow for an overall assessment of the PTW safety level in the European road network relative to other modes of transport, providing thus useful support to decision makers working for the improvement of safety in the European road network. Of course, the effort of data-collection is an on-going challenge and there are additional data that could help shed light to the problem of road safety. Of particular interest are exposure data. Furthermore, the macroscopic analysis presented in this paper could in the future be combined with in-depth analysis of intersection accident data, thus providing further insight into the causes and impacts of PTW accidents.

Acknowledgements

This paper is based on work carried out within the scope of the SafetyNet (The European Road Safety Observatory) and DaCoTA (Data Collection Transfer and Analysis) projects of the 6th and 7th (respectively) Framework Programs for Research, Technological Development and Demonstration of the European Commission.

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Appendix A. Country Abbreviations used

BE Belgium LU Luxembourg

CZ Czech Republic NL Netherlands

DK Denmark AT Austria

IE Ireland PT Portugal

EL Greece RO Romania

ES Spain FI Finland

FR France SE Sweden

IT Italy UK United Kingdom

EU-23 = EU-16 +

DE Germany

EE Estonia

LV Latvia

HU Hungary

PL Poland

SK Slovakia

SI Slovenia