83 Unfall und Mensch
Nigeria ranks one of the highest countries in the world with the largest accident, especially when measured by whiplash associated disorders, whereas, traffic safety education rate, data and information been widely known as preventive indicators have been grossly neglected. In Nigeria, traffic safety enlightenment, awareness, political understanding and appreciation of the problem's magnitude are lacking. This study, therefore, seeks to understand and document the fact that accident causation factors in Nigeria relate more to the problem of development, poverty, knowledge and education as evidenced in most other developing countries. Among the primary accident causation factors on Nigerian roads are: - lack of a transportation system or multi-model integration - sub-standard and obsolete vehicles and road furniture - poor road maintenance, investment and engineering management - paucity of road users' and drivers' knowledge, skill, enlightenment and education of the road Use This paper submits that Nigeria being a developing nation requires purely primitive strategies being cost effective (health wise) than curative measures. It is in this light that an enduring, comprehensive and sustainable traffic safety educational programmes information base and data inventory, analysis and implementations form the focus of this study. This effort will provide basic guidelines framework and implementation procedure for a successful prevention of whiplash associated disorder resulting from road traffic crashes in Nigeria and other parts of the world.
This contribution introduces a number of psychological methods of analysis that are based on the practice-oriented collection of information directly at the site of an accident and that allow for an analysis and coding of the accident causes. Investigation examples and examples of the data combinations with basic medical and technical data are outlined. Objective of the collection is the inter-disciplinary investigation of human factors in the causes of accidents ("human-factor-analysis"). The psychological data are incorporated according to an integrative model for accident causes based on empiric algorithms in the data base of the accident research, where the clustered evaluation potential of comprehensive factors of the accident development can be illustrated. The central theoretical concept for the basic model of the progress of the accident from a psychological point of view comprises psychological indicators for the evaluation of the site of the accident for the analysis of the perception conditions as well as a classification of the gleaned data into the accident progress model according to chronological and local criteria. Perception conditions, action intentions and executions as well as conditions limiting perception and actions are acquired, using a questionnaire for persons involved in an accident, and are also integrated into the data structure concerning weighted feature characteristics as well as combined with other relevant features. Suitable systematization tools for the collection and coding of psychological accident development parameters have to be provided, which require primarily a model image of the corresponding processes from the persons involved in the accident (perceptions, expectations, decisions, actions). The interactive accident model contains components of the models by KÜTING 1990, MC DONALD 1972, SURREY 1969 and RASMUSSEN 1980. Based on the inter-action of the three partial systems "person", "vehicle" and "environment", the first step is the assessment of the situation by the persons involved in the accident. This is dependent on the personal attitudes and motives, on experiences and expectations concerning the progress of the situation. Subsequently, data concerning the manner of the coping with the ambiguous state as well as with the instable state (emergency reaction immediately before the accident occurs) are collected. The factors relating to the persons involved in the accident are gathered on several levels using corresponding questionnaires. The coding of the found and collected characteristics is conducted in a multidimensional evaluation relating to the technical results of the accident reconstruction and of the psychological classification, which are subsequently integrated in coded form into the data base of the accident research. The result of this analysis is a description of the development of the accident depicted on a chronological vector from a perception and decision theoretical perspective. This is explained in detail using exemplary cases.
Interaction of road environment, vehicle and human factors in the causation of pedestrian accidents
(2005)
The UK On-the-Spot project (OTS) completed over 1500 in-depth investigations of road accidents during 2000-2003 and is continuing for a further 3 years. Cases were sampled from two regions of England using rotating shifts to cover all days of the week and all hours of the day and night. Research teams were dispatched to accidents notified to police during the shifts; arrival time to the scene of the accident was generally less than 20 minutes. The methodology of OTS includes sophisticated systems for describing accident causation and the interaction of road, vehicle and human factors. The purpose of this paper is to describe and illustrate these systems by reference to pedestrian accidents. This type of analysis is intended to provide an insight into how and why pedestrian accidents occur in order to assist the development of effective road, vehicle and behavioural countermeasures.
76 severe traffic accidents had been investigated in depth in an ongoing Volkswagen-Tongji University joint accident research project in JiaDing district, Shanghai, PR China since June 2005. With a methodology similar to German accident research units in Dresden and Hannover, a research team proceeds to the scene immediately after the incident to investigate and collect various data on environment, accident occurrence, vehicle state and deformations as well as injuries. The data combined with the results of accident reconstruction will be stored in a database for further statistical and casuistic analysis. The first outcome of the project supports the hypothesis that a main causation for the large number of traffic accidents in China is the lacking of risk awareness in Chinese driver behaviour. Low seat-belt use and the high proportion of vulnerable and poorly protected two-wheelers in traffic are reasons for the high injury and fatality rate in China. The research work shows that accident research in China is feasible and able to give support to tackle one of the urging problems in Chinese development.
The "Seven Steps Method" is an analysis and classification system, which describes the human participation factors and their causes in the temporal sequence (from the perceptibility to concrete action errors) taking into consideration the logical sequence of individual basic functions. By means of the "seven steps" it is possible to describe the relevant human causes of accidents from persons involved in the accident in an economic way with a sufficient degree of exactitude, because the causes can be further differentiated in their value (e.g. diversion as external diversion with regard to impact due to surroundings) and their sub values (e.g. external diversion with regard to impact due to surroundings in the shape of a "capture" of the perception by a prominent object of the traffic environment). Theoretically it is possible that one or more causing moments can be assigned to a person involved in an accident in each of the "seven steps"; however it is also possible to sufficiently clarify the cause in only one level (examples for this are described). In the practice of accident investigation at the site of the accident, the sequence chart is also relevant. With its assistance the questioning of the people involved in an accident can be accomplished in a structured way by assigning a set of questions to each step.
This study aimed to identify the occurrence, type and mechanisms of the traumatic injuries of the vulnerable road users in vehicle collisions, and to determine the effects of human, engineering, and environment factors on traffic accidents and injuries. The pedestrian accident cases were collected in the years 2000 to 2005 from Changsha Wujing hospital China and Accident Research Unit at Medical University Hannover in Germany. A statistic analysis was carried out using the collected accident data. The results from analysis of Changsha data were compared with results from analysis of GIDAS data Hannover. The injury severities were determined using AIS code and ISS values. The results were presented in terms of cause of injuries, injury distributions, injury patterns, injury severity. The factors influenced the injury outcomes were proposed and discussed for the vehicle transport environment and road users. The results were discussed with regard to accident data collection, accident sampling and injury distributions etc. In the urban area of Changsha, motorcycles and passenger cars are most frequently involved in vehicle pedestrian accidents. Head and lower extremities injuries are the predominant types of pedestrian injuries. The pedestrian accidents were identified as vital issue in urban traffic safety and therefore a high priority should be given to this road user group in research of safe urban transportation. In Hannover area, cars are most frequently involved in traffic accidents, injured pedestrians are involved in road traffic of Germany in 13% of all causalities only in 2005 and have nearly the same number as motorcyclists, but the half of bicyclists.
Validation of human pedestrian models using laboratory data as well as accident reconstruction
(2007)
Human pedestrian models have been developed and improved continually. This paper shows the latest stage in development and validation of the multibody pedestrian model released with MADYMO. The biofidelity of the multibody pedestrian model has been verified using a range of full pedestrian-vehicle impact tests with a large range in body sizes (16 male, 2 female, standing height 160-192cm, weight 53.5-90kg). The simulation results were objectively correlated to experimental data. Overall, the model predicted the measured response well. In particular the head impact locations were accurately predicted, indicated by global correlation scores over 90%. The correlation score for the bumper forces and accelerations of various body parts was lower (47-64%), which was largely attributed to the limited information available on the vehicle contact characteristics (stiffness, damping, deformation). Also, the effects of the large range in published leg fracture tolerances on the predicted risk to leg fracture by the pedestrian model were evaluated and compared with experimental results. The validated mid-size male model was scaled to a range of body sizes, including children and a female. Typical applications for the pedestrian models are trend studies to evaluate vehicle front ends and accident reconstructions. Results obtained in several studies show that the pedestrian models match pedestrian throw distances and impact locations observed in real accidents. Larger sets of well documented cases can be used to further validate the models especially for specific populations as for instance children. In addition, these cases will be needed to evaluate the injury predictive capability of human models. Ongoing developments include a so-called facet pedestrian model with a more accurate geometry description and a more humanlike spine and neck and a full FE model allowing more detailed injury analysis.
Powered Two Wheelers (PTWs) accidents constitute one of the road safety problems in Europe. PTWs fatalities represent 22% at EU level in 2006, having increased during last years, representing an opposite trend compared to other road users" figures. In order to reduce these figures it is necessary to investigate the accident causation mechanisms from different points of view (e.g.: human factor, vehicle characteristics, influence of the environment, type of accident). SAFERIDER project ("Advanced telematics for enhancing the SAFEty and comfort of motorcycle RIDERs", under the European Commission "7th Framework Program") has investigated PTW accident mechanisms through literature review and statistical analyses of National and In-depth accident databases; detecting and describing all the possible PTW's accident configurations where the implementation of ADAS (Advanced Driver Assistance Systems) and IVIS (In-Vehicle Information Systems) could contribute to avoid an accident or mitigate its severity. DIANA, the Spanish in-depth database developed by CIDAUT, has been analyzed for that purpose. DIANA comprises of accident investigation teams, in close cooperation with police forces, medical services, forensic surgeons, garages and scrap yards. An important innovation is the fact that before injured people arrive to hospitals, photographs and explanations about the possible accident injury mechanisms are sent to the respective hospitals (via 3G GPRS technology). By this, additional information to medical staff can be provided in order to predict in advance possible internal injuries and select the best medical treatment. This methodology is presented in this paper. On the other hand, the main results (corresponding to road, rider and PTW characteristics; pre and post-accident manoeuvres; road layout; rider behaviour; impact points; accident causations;...) from the analyses of the PTW accidents used for SAFERIDER are shown. Only accident types relevant to ADAS and IVIS devices have been considered.
In the context of the COST357 research project, the climatic conditions and requirements for protective helmets for motorcyclists have been examined. The extent to which these factors would influence motorbike handling and accidents in which motorcyclists are involved have also been examined. This project addresses how cognitive abilities of motorcyclists relate to helmet construction factors. In particular, the aspects of motorcycle driver helmets are to be parameterized in order that they may be used subsequently as a basis for future requirement profiles. The task of one working group of the COST357 project has been to analyse accident events and to identify helmet design issues which affect motorcycle drivers while wearing a helmet. This has been achieved by collating accident data across different countries recorded in the course of in-depth investigations at the site of accidents and by combining this with field studies of motorcyclists participating in traffic, but not involved in accidents. This paper presents the study methodology, database and first results of this international survey. The basis of the study has been a total of 424 interviews of motorcyclists and 134 motorcycle accidents, which were collected across Germany, Greece, Italy, Ireland, Portugal and Turkey and combined in a single database.
Relevant accident related factors : risk and frequencies of contributing to road traffic accidents
(2009)
In the course of the European Project TRACE (Traffic Accident Causation in Europe) an attempt was made to analyse the cause of road traffic accidents from a factors' point of view. By literature review the most important independent risk factors for traffic accidents were identified to be speed, alcohol intake, male gender, young age, cell phone use, and fatigue. However, the impact of an accident related factor also depends on its prevalence in traffic and accidents, respectively. Available to the Partners in the TRACE Project were different accident databases. Causally contributing factors found by accident investigations that are most often coded in accident databases are connected to unadapted speed and inattention. Taking into account the risk increase and the frequency of contribution to accidents the conclusion can be drawn that the most relevant factors for accident causation are: "alcohol", "speed", and "inattention and distraction".
As the official German catalogue of accident causes has difficulty in matching the increasing demands for detailed psychologically relevant accident causation information, a new system, based on a "7 Steps" model, so called ACASS, for analyzing and collecting causation factors of traffic accidents, was implemented in GIDAS in the year 2008. A hierarchical system was developed, which describes the human causation factors in a chronological sequence (from the perception to concrete action errors), considering the logical sequence of basic human functions when reacting to a request for reaction. With the help of this system the human errors of accident participants can be adequately described, as the causes of each range of basic human functions may be divided into their characteristics (influence criteria) and further into specific indicators of these characteristics (e.g. distraction from inside the vehicle as a characteristic of an observation-error and the operation of devices as an indication for distraction from inside the vehicle. The causation factors accordingly classified can be recorded in an economic way as a number is assigned to each basic function, to each characteristic of that basic function and to each indicator of that characteristic. Thus each causation factor can be explicitly described by means of a code of numbers. In a similar way the causation factors based on the technology of the vehicle and the driving environment, which are also subdivided in an equally hierarchical system, can be tagged with a code. Since the causes of traffic accidents can consist of a variety of factors from different ranges and categories, it is possible to tag each accident participant with several causation factors. This also opens the possibility to not only assign causation factors to the accident causer in the sense of the law, but also to other participants involved in the accident, who may have contributed to the development of the accident. The hierarchical layout of the system and the collection of the causation factors with numerical codes allow for the possibility to code information on accident causes even if the causation factor is not known to its full extent or in full detail, given the possibility to code only those cause factors, which are known. Derived from the systematic of the analysis of human accident causes ("7 steps") and from the practical experiences of on-scene interviews of accident participants, a system was set in place, which offers the possibility to extensively record not only human causation factors in a structured form. Furthermore, the analysis of the human causation factors in such a structured way provides a tool, especially for on-scene accident investigations, to conduct the interview of accident participants effectively and in a structured way.
Abstract: The number of accidents that can be attributed to driving under the influence of psychoactive substances (alcohol, drugs, and certain medicines) is constantly on a high level with drugs and medicines proportionally increasing over the years. The overall objective of the EU 6th Framework Programme project DRUID is to gain better knowledge of the various aspects of driving under the influence of drugs, alcohol and medicines. DRUID wants to offer scientific support to EU transport policy makers by suggesting guidelines and measures to combat impaired driving. To reach this ambitious aim a wide range of studies is conducted. The various studies are divided into seven work packages with complex interdependencies. There are experimental studies assessing the effects of single and combined psychoactive substances on driving performance (WP1) as well as epidemiological studies aiming to assess the situation in Europe regarding prevalence of alcohol and other psychoactive substances in drivers (WP2).The principal objective of these studies is to gain relative risk estimates for traffic accident involvement of drivers impaired by psychoactive substances and to recommend substance concentration thresholds. A theoretical framework which allows the integration of the experimental and epidemiological findings serves as a fundament for developing these recommendations. WP3 aims at improving the possibilities of detecting drug driving in Europe. Police forces evaluate practically (under realistic enforcement conditions) oral fluid screening devices. A scientific evaluation of oral fluid screening devices and other methods (i.e. roadside checklists of signs of impairment) is done as well. The outcome of the practical and scientific evaluations serves as input to cost-benefit analyses of enforcement.
The paper presents a methodology for the benefit estimation of several secondary safety systems for pedestrians, using the exceptional data depth of GIDAS. A total of 667 frontal pedestrian accidents up to 40kph and more than 500 AIS2+ injuries have been considered. In addition to the severity, affected body region, exact impact point on the vehicle, and the causing part of every injury, the related Euro NCAP test zone was determined. One results of the study is a detailed impact distribution for AIS2+ injuries across the vehicle front. It can be stated, how often a test zone or vehicle part is hit by pedestrians in frontal accidents and which role the ground impact plays. Basing on that, different secondary safety measures can be evaluated by an injury shift method concerning their real world effectiveness. As an example, measures concerning the Euro NCAP pedestrian rating tests have been evaluated. It was analysed which Euro NCAP test zones are the most effective ones. In addition, real test results have been evaluated. Using the presented methodology, other secondary safety like the active bonnet (pop-up bonnet) or a pedestrian airbag measures can be evaluated.
Over 3,814 young drivers died in European Countries in 2004. Based on the recent OECD study: "Young drivers: the road to safety" (OECD, 2006), this paper addresses the question of the factors contributing to this high risk, and it draws together the experiences of many countries in reducing this risk. The comparisons across countries show that young driver safety is related to the quality of the traffic system. Safe countries have also safe young drivers, demonstrating that raising general safety levels is beneficial for young novice drivers. The analysis of the developments over time reveals that young males in contrast to young females have not benefited enough from the latest safety measures, indicating the need for a better understanding of the nature of the young male driver accident proneness. Although, recent studies on brain development indicate that youngsters may not be sufficiently physiologically matured to handle complex and dangerous tasks such as car driving, crash patterns indicate that enhanced driving experience may have protective effects. The paper closes with a 9 point policy plan. The full OECD report (258 pages) can be downloaded for free from http://internationaltransportforum.org/Pub/pdf/06YoungDrivers.pdf.
The significant demographic changes are predicted for the European future. The age group over 65 years is permanently increasing and over next 30 years every fourth person will belong to this group. This development will continue so far that by 2050 in many countries will double the percentage of the population aged 65 and more. Many studies analyze the new phenomena of the ageing (graying) society during the last decade. Mobility is integrated part of the life of every citizen, even more it means for the elderly people. The adequate mobility is the precondition for their active life and for their social communication that contribute to their health and functional capacity and their autonomy and independency. The active seniors demand less public support. The mobility of the older citizens is closely linked with health and societal problems and creates an important public challenge. On the other side the participation of seniors in transport due to their limited physical and mental possibilities means for them an increased risk to be injured or killed. The main mobility spaces are roads that can be used not only as a traveler in a vehicle (driver or passenger) but also as a pedestrian or cyclist or even as a motorcyclist. The road traffic is then an opportunity and danger in the same time. The accident analyzes show specific risk features of seniors that are different compared with other age groups. First of all the older road users (65 and more) are facing to the higher risk (number of killed divided by the population size) to be killed in a road accident compared with the group of younger road users (0 - 64). More significant difference can be observed when comparing the road user groups. The fatality percentage of the older pedestrians is 2,5 times higher compared with the group 25 " 64. Similar frequency show the cyclist fatalities. On the other side the vehicle passengers in the younger group have more or less two time higher percentage compared to seniors and in the group of motorcyclists even achieved in 2008 almost five times higher compared with the older group. The share of the old road users fatalities (around 19%) didn"t practically change during the last 10 years in the European average. But comparing the gender involvement (2006) there is an interesting difference " female fatalities make 30, 2%, male fatalities 15, 3% of all fatalities in their groups. The risk of the senior users is more connected with their physical and mental limits than with their risk behavior. According to the Czech statistics (2007) the vehicle drivers over 65 years cause only 3, 6% of all accidents. The solution of the problem is to minimize the risk and to create a safe environment for the elderly people using the roads. In order to achieve this goal a deep knowledge of risk and of accident circumstances, full understanding of the behavior of the seniors and their limitations and accommodating approach of the whole society is necessary. Road risk of the ageing society has to be considered as a part of the health and social policy. These can build a creditable basis for the implementation of the measures that secure safe moving of seniors on the roads.
Accidents involving two wheels vehicles represent one of the more important types of accidents in Europe. These accidents are usually not easy to reconstruct specially for the analysis of the injuries and its correlation with accident dynamics and evidences. Different methodologies are applied in this work for the reconstruction of two wheeler accidents, especially accident involving motorcycles. From the typologies of road evidences like skid marks, to the use of Pc-Crash and the use of Madymo models, different reconstruction of real accidents are presented. One of the questions that sometimes arise for legal purposes when some type of head injuries arise is if the occupant was wearing or not a helmet. The correlation of head injuries with the use of the helmet is a very important issue, therefore an important legal aspect. One of the key questions for the reconstructions that is difficult to analyze, is if the vehicle occupant, was or not, wearing the helmet. Based on the previously collected information, a generic model of a helmet was developed on CAD 3D, followed by its conversion into finite elements, all in order to perform impact tests using the Madymo software that would help improve the helmet- safety, but that also can be used as a tool in accident reconstruction.
Accident data shows that the vast majority of pedestrian accidents involve a passenger car. A refined method for estimating the potential effectiveness of a technology designed to support the car driver in mitigating or avoiding pedestrian accidents is presented. The basis of the benefit prediction method consists of accident scenario information for pedestrian-passenger car accidents from GIDAS, including vehicle and pedestrian velocities. These real world pedestrian accidents were first reconstructed and the system effectiveness was determined by comparing injury outcome with and without the functionality enabled for each accident. The predictions from Volvo Cars" general Benefit Estimation Model are refined by including the actual system algorithm and sensing models for a relevant car in the simulation environment. The feasibility of the method is proven by a case study on a authentic technology; the Auto Brake functionality in Collision Warning with Full Auto Brake and Pedestrian Detection (CWAB-PD). Assuming the system is adopted by all vehicles, the Case Study indicates a 24% reduction in pedestrian fatalities for crashes where the pedestrians were struck by the front of a passenger car.
Immediate user self-evacuation is crucial in case of fire in road tunnels. This study investigated the effects of information with or without additional virtual reality (VR) behavioural training on self-evacuation during a simulated emergency situation in a road tunnel. Forty-three participants were randomly assigned to three groups with accumulating preventive training: The control group only filled in questionnaires, the informed group additionally read an information brochure on tunnel safety, and the VR training group received an additional behavioural training in a VR tunnel scenario. One week later, during the test session, all participants conducted a drive through a real road tunnel in which they were confronted with a collision of two vehicles and intense smoke. The informed and the behaviourally trained participants evacuated themselves more reliably from the tunnel than participants of the control group. Trained participants showed better and faster behavioural responses than informed only participants. Interestingly, the few participants in the control group who reacted adequately to the scenario were all female. A 1 year follow-up online questionnaire showed a decrease of safety knowledge, but still the trained group had somewhat more safety relevant knowledge than the two other groups. Information and especially VR behavioural training both seem promising to foster adequate self-evacuation during crisis situations in tunnels, although long term beneficial behavioural effects have to be demonstrated. Measures aiming to improve users/ behaviour should take individual difference such as gender into account.
To determine whether the model "Accompanied driving from age 17" (AD17) contributes to improvement of young drivers' road safety, two large random samples of novice drivers drawn from the Central Register of Driving Licences (ZFER) held at the Federal Motor Transport Authority (KBA) were compared in terms of the rates of accident involvement and traffic offences at the start of their solo driving career. The samples comprised former participants in the AD17 model and novice drivers of the same age who had obtained a driving licence in the conventional manner immediately after their 18th birthday. Both analysis groups were contacted by post and asked to complete an online questionnaire. In response, 19,000 drivers reported on their first year of solo driving and on the occurrence of any accidents or traffic offences during this period. The analyses were repeated with two "silent" analysis groups comprising a total of 75,000 drivers, for whom any records of traffic offences were retrieved from the Central Register of Traffic Offenders (VZR), with a distinction being made between offences in connection with an accident and other offences. The AD17 model was introduced in all 16 German federal states between April 2004 and January 2008. By the end of 2009, almost one million novice drivers had participated in the model, and almost three-quarters of the target group - so-called "early beginners" who wished to commence solo driving immediately after reaching the age of 18 years - opted for the AD17 model. The phase of introduction of the model was associated with a temporary increase of around five per cent in the demand for driving licences from persons under 19 years of age. During the first year of solo driving, the rate of accident involvement for AD17 participants was 19 per cent lower and the rate of traffic offences 18 per cent lower than for drivers of the same age who had obtained their driving licence in the conventional manner. After adjustment for confounds (e.g. gender and vehicle availability), a reduction in accidents by 17 per cent and in traffic offences by 15 per cent remained as an effect attributable to the model. A comparison on the basis of the distances driven indicated 22 per cent fewer accidents and 20 per cent fewer traffic offences. The results are statistically significant and apply to both male and female drivers. The findings were confirmed in the replication study based on VZR data, with one exception: For female AD17 drivers, and here only for VZR-recorded offences excluding accidents, no significant reduction was found. On the other hand, the rate for female drivers is already lower than that of their male counterparts by three-quarters. Approximately 1,700 injury accidents were prevented by implementation of the model in 2009.
From literature well-known analyzes on risks, hazards and causes of accidents of older drivers are amended by the present study in which a comparison of the specific features of accident causes of older car drivers (older than 60 years) and of younger car drivers (under 25 years) is conducted. Mainly the question is pursued if specific errors, mistakes and lapses are predominant in the two different age groups. The analysis system ACAS (Accident Causation Analysis System) used hereby consists of a sequential system of accident causation factors from the human, the technical and the infrastructural field, whereupon for this study the influence of the human features on the accident development in two different age groups is of interest. ACAS is both an accident model and an analysis and classification system, which describes the human participation factors of an accident and their causes in the temporal sequence (from the perceptibility to concrete action errors) taking into consideration the logical sequence of individual basic functions. In five steps (categories) of a logical and temporal sequence the hierarchical system makes human functions and processes as determinants of accident causes identifiable. The methodology specifically focuses on the use in so-called "In-Depth" and "On-Scene" investigation studies. With the help of the system for each accident participant one or more of five hypotheses of human cause factors are formed and then specified by appropriate verification criteria. These hypotheses in turn are further specified by indicators in such manner that the coding of the causation factors by a code system meets the needs of database processing and are accessible to a quantitative data analysis. The first results of the descriptive comparison of the two age groups concern mainly differences in the functional levels "information admission/perception" (where the elderly drivers have more difficulties than the young ones) and "information processing/evaluation" (where the younger drivers show more problems). Concerning the cognitive function of "planning" the group of younger drivers seems to be more often involved in an accident because of excessive speed.
The effect of fatigue on driving has been compared to the effect of alcohol impairment in both driver performance and crash studies. However are crash characteristics and causation mechanisms similar in crashes involving fatigue to those involving alcohol when studied in the real world? This has been explored by examining data held in the EC project SafetyNet Accident Causation Database. Causation data was recorded using the SafetyNet Accident Causation System (SNACS). The focus was on Cars/MPV crashes and drivers assigned the SNACS code Alcohol or Fatigue. The Alcohol group included 44 drivers and the Fatigue group included 47. "Incorrect direction" was a frequently occurring critical event in both the Alcohol and Fatigue groups. The Alcohol group had more contributory factors related to decision making and the Fatigue group had more contributory factors relating to incorrect observations. This analysis does not allow for generalised statements about the significance of the similarities and differences between crashes involving alcohol and fatigue, however the observed differences do suggest that attempts to quantify the effect of fatigue by using levels of alcohol impairment as a benchmark should be done with care.
Analysis of the accident scenario of powered two-wheelers on the basis of real-world accidents
(2013)
For the first time since 20 years the German national statistics of traffic accidents revealed an increasing number of fatalities and seriously injured persons in 2011. This negative development was especially caused by increasing numbers in all groups of vulnerable road users (VRU). Furthermore, the comparison of fatality reduction rates between several categories of road users shows that persons on motorcycles show the worst performance over years. Although every second fatality in German traffic accidents is still a car occupant, users of PTW make up more than 20% in the meantime. Assuming further improvements in the field of occupant protection this trend will continue. For that reason, a study on the basis of real-world accidents was conducted to describe the accident scenario involving motorcycles and to identify the reasons of the above-described fact. Approximately 1.800 motorcycle accidents out of GIDAS database were used for the analyses. The first part of the study deals with the question how representative the GIDAS database is for the German motorcycle accident scenario. Afterwards, detailed descriptive statistics on motorcycle accidents were presented considering numerous parameters about the accident scene, environmental influences, vehicle information, individual characteristics, interview data, injury severity and injury causation. One important point is the identification of the most frequent critical situations that are typical for motorcycle accidents. Furthermore, a special focus was on accident causation. Finally, conspicuous facts out of the analysis are emphasized. All in all, the study gives a comprehensive overview about the German motorcycle accident scenario. One the one hand, the use of weighted GIDAS data allows representative and robust statements on the basis of large case numbers; on the other hand highly detailed conclusions can be drawn. The results of the study help to understand the particularities of motorcycle accidents and provide approaches for further improvements in the field of PTW safety.
In 2011 399 cyclists died in road accidents in Germany and another 76.351 cyclists have been injured. Since 2000 the number of injured or fatally injured cyclists remained on the same high level. Cyclists form 19% of all casualties in German road traffic, although the modal split rate of this transport mode in 2008 was only 10% of trips and resp. 3% of kilometres per day. The high proportion of fatally and seriously injured shows the high vulnerability of cyclists. The demographic shift towards an older population in Germany and the governmental recommendation of increased bicycle use as an ecological, economical and healthy alternative to other modes of transport lead to the assumption that bicycle use especially of elderly people will increase. Based on these facts about the German cyclists' situation a representative survey of 2.000 cyclists was conducted. Results display use patterns and accident involvement on a descriptive level. Overall 7.7% of cyclists report to have been involved in at least one road traffic accident within the last three years. The performed path model analysis reveals an acceptable model fit. Though the explained variance of accident involvement of the applied psychological factors was low, significant relations between several of these factors and especially risky behaviour could be found.
Introduction: The method of causation analysis applied under the German accident survey GIDAS, which is based on Accident Causation Analysis System (ACAS) focuses on an on-scene data collection of predominantly directly event-related causation factors which were crucial in the accident emergence as situational resulting events and influences. The paradigm underlying this method refers to the findings of the psychological traffic accident research that most causally relevant features of the system components human, infrastructure and vehicle technology are found directly in the situation shortly before the accident. This justifies the survey method which is conducted directly at the accident (on-scene), shortly after the accident occurrence (in-time) with the detection of human-related causes (in-depth). Human aspects of the situation analysis that interact and influence the risk situations shortly before the collision are reported as errors, lapses, mistakes and failures in ACAS in specific categories and subcategories. Thus methodically ACAS is designed primarily for the collection of accident features on the level of operational action, which certainly leads to valid findings and behavioral causes of accidents. The enhancement by means of Moderating Conditions concerns the pre-crash phase in different levels: strategical, tactical and operational.