811 resultados para Road, bridge and tunnel sector


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Driving is a vigilance task, requiring sustained attention to maintain performance and avoid crashes. Hypovigilance (i.e., marked reduction in vigilance) while driving manifests as poor driving performance and is commonly attributed to fatigue (Dinges, 1995). However, poor driving performance has been found to be more frequent when driving in monotonous road environments, suggesting that monotony plays a role in generating hypovigilance (Thiffault & Bergeron, 2003b). Research to date has tended to conceptualise monotony as a uni-dimensional task characteristic, typically used over a prolonged period of time to facilitate other factors under investigation, most notably fatigue. However, more often than not, more than one exogenous factor relating to the task or operating environment is manipulated to vary or generate monotony (Mascord & Heath, 1992). Here we aimed to explore whether monotony is a multi-dimensional construct that is determined by characteristics of both the task proper and the task environment. The general assumption that monotony is a task characteristic used solely to elicit hypovigilance or poor performance related to fatigue appears to have led to there being little rigorous investigation into the exact nature of the relationship. While the two concepts are undoubtedly linked, the independent effect of monotony on hypovigilance remains largely ignored. Notwithstanding, there is evidence that monotony effects can emerge very early in vigilance tasks and are not necessarily accompanied by fatigue (see Meuter, Rakotonirainy, Johns, & Wagner, 2005). This phenomenon raises a largely untested, empirical question explored in two studies: Can hypovigilance emerge as a consequence of task and/or environmental monotony, independent of time on task and fatigue? In Study 1, using a short computerised vigilance task requiring responses to be withheld to infrequent targets, we explored the differential impacts of stimuli and task demand manipulations on the development of a monotonous context and the associated effects on vigilance performance (as indexed by respone errors and response times), independent of fatigue and time on task. The role of individual differences (sensation seeking, extroversion and cognitive failures) in moderating monotony effects was also considered. The results indicate that monotony affects sustained attention, with hypovigilance and associated performance worse in monotonous than in non-monotonous contexts. Critically, performance decrements emerged early in the task (within 4.3 minutes) and remained consistent over the course of the experiment (21.5 minutes), suggesting that monotony effects can operate independent of time on task and fatigue. A combination of low task demands and low stimulus variability form a monotonous context characterised by hypovigilance and poor task performance. Variations to task demand and stimulus variability were also found to independently affect performance, suggesting that monotony is a multi-dimensional construct relating to both task monotony (associated with the task itself) and environmental monotony (related to characteristics of the stimulus). Consequently, it can be concluded that monotony is multi-dimensional and is characterised by low variability in stimuli and/or task demands. The proposition that individual differences emerge under conditions of varying monotony with high sensation seekers and/or extroverts performing worse in monotonous contexts was only partially supported. Using a driving simulator, the findings of Study 1 were extended to a driving context to identify the behavioural and psychophysiological indices of monotony-related hypovigilance associated with variations to road design and road side scenery (Study 2). Supporting the proposition that monotony is a multi-dimensional construct, road design variability emerged as a key moderating characteristic of environmental monotony, resulting in poor driving performance indexed by decrements in steering wheel measures (mean lateral position). Sensation seeking also emerged as a moderating factor, where participants high in sensation seeking tendencies displayed worse driving behaviour in monotonous conditions. Importantly, impaired driving performance was observed within 8 minutes of commencing the driving task characterised by environmental monotony (low variability in road design) and was not accompanied by a decline in psychophysiological arousal. In addition, no subjective declines in alertness were reported. With fatigue effects associated with prolonged driving (van der Hulst, Meijman, & Rothengatter, 2001) and indexed by drowsiness, this pattern of results indicates that monotony can affect driver vigilance, independent of time on task and fatigue. Perceptual load theory (Lavie, 1995, 2005) and mindlessness theory (Robertson, Manly, Andrade, Baddley, & Yiend, 1997) provide useful theoretical frameworks for explaining and predicting monotony effects by positing that the low load (of task and/or stimuli) associated with a monotonous task results in spare attentional capacity which spills over involuntarily, resulting in the processing of task-irrelevant stimuli or task unrelated thoughts. That is, individuals – even when not fatigued - become easily distracted when performing a highly monotonous task, resulting in hypovigilance and impaired performance. The implications for road safety, including the likely effectiveness of fatigue countermeasures to mitigate monotony-related driver hypovigilance are discussed.

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Design-Build (DB) project delivery systems have increasingly been adopted by many private and public sector organizations worldwide due to its many advantages. However, many Indonesian road infrastructure projects are still delivered using the traditional design-bid-build (DBB) project delivery system. This paper reviews the existing literature to explore factors that can influence the successful implementation of DB project delivery system in Indonesian road infrastructure projects. It founds the lack of clarification in existing legislations as well as the lack of experiences, knowledge and skill as the main obstacles in implementing DB systems in Indonesia. To overcome these obstacles, this paper proposes (1) A relook at existing legislation in term of providing more guidance on determining projects appropriate for the DB, procedures for implementing DB, and the structure of builder entity; (2) To develop the skills and knowledge of DB to all stakeholders through communications, knowledge sharing and training. The outcome of this review can serve as a guide to development a framework for the implementation of the design-build project delivery system in Indonesian road infrastructure projects.

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An automatic approach to road lane marking extraction from high-resolution aerial images is proposed, which can automatically detect the road surfaces in rural areas based on hierarchical image analysis. The procedure is facilitated by the road centrelines obtained from low-resolution images. The lane markings are further extracted on the generated road surfaces with 2D Gabor filters. The proposed method is applied on the aerial images of the Bruce Highway around Gympie, Queensland. Evaluation of the generated road surfaces and lane markings using four representative test fields has validated the proposed method.

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Transport and Storage Sector - Identified as one of 4 primary targets in the National Occupational Health and Safety Strategy 2002-2012 (NOHSS) The Heavy Vehicle Industry -80% of the freight task -29% of the employees in Transport and Storage 5 years on: -Transport and Storage - 22% reduction -Heavy Vehicle Industry - only an 11% reduction Intervention strategies that aren’t targeted to a specific audience may have differing levels of success due to cultural beliefs and values (McLeroy et al., 1994) Research Goal: - To explore the influence of culture on safety in the heavy vehicle industry

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Accurate and detailed road models play an important role in a number of geospatial applications, such as infrastructure planning, traffic monitoring, and driver assistance systems. In this thesis, an integrated approach for the automatic extraction of precise road features from high resolution aerial images and LiDAR point clouds is presented. A framework of road information modeling has been proposed, for rural and urban scenarios respectively, and an integrated system has been developed to deal with road feature extraction using image and LiDAR analysis. For road extraction in rural regions, a hierarchical image analysis is first performed to maximize the exploitation of road characteristics in different resolutions. The rough locations and directions of roads are provided by the road centerlines detected in low resolution images, both of which can be further employed to facilitate the road information generation in high resolution images. The histogram thresholding method is then chosen to classify road details in high resolution images, where color space transformation is used for data preparation. After the road surface detection, anisotropic Gaussian and Gabor filters are employed to enhance road pavement markings while constraining other ground objects, such as vegetation and houses. Afterwards, pavement markings are obtained from the filtered image using the Otsu's clustering method. The final road model is generated by superimposing the lane markings on the road surfaces, where the digital terrain model (DTM) produced by LiDAR data can also be combined to obtain the 3D road model. As the extraction of roads in urban areas is greatly affected by buildings, shadows, vehicles, and parking lots, we combine high resolution aerial images and dense LiDAR data to fully exploit the precise spectral and horizontal spatial resolution of aerial images and the accurate vertical information provided by airborne LiDAR. Objectoriented image analysis methods are employed to process the feature classiffcation and road detection in aerial images. In this process, we first utilize an adaptive mean shift (MS) segmentation algorithm to segment the original images into meaningful object-oriented clusters. Then the support vector machine (SVM) algorithm is further applied on the MS segmented image to extract road objects. Road surface detected in LiDAR intensity images is taken as a mask to remove the effects of shadows and trees. In addition, normalized DSM (nDSM) obtained from LiDAR is employed to filter out other above-ground objects, such as buildings and vehicles. The proposed road extraction approaches are tested using rural and urban datasets respectively. The rural road extraction method is performed using pan-sharpened aerial images of the Bruce Highway, Gympie, Queensland. The road extraction algorithm for urban regions is tested using the datasets of Bundaberg, which combine aerial imagery and LiDAR data. Quantitative evaluation of the extracted road information for both datasets has been carried out. The experiments and the evaluation results using Gympie datasets show that more than 96% of the road surfaces and over 90% of the lane markings are accurately reconstructed, and the false alarm rates for road surfaces and lane markings are below 3% and 2% respectively. For the urban test sites of Bundaberg, more than 93% of the road surface is correctly reconstructed, and the mis-detection rate is below 10%.

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Design-build (DB) project delivery systems have increasingly been adopted by many private and public sector organizations worldwide due to the many advantages offered on projects by such systems. However, many Indonesian road infrastructure projects are still delivered using the traditional design-bid-build (DBB) project delivery system. In order to provide evidence of the benefits of DB, it is essential to identify the factors that can contribute to successful DB implementation and this paper aims to provide evidence of such factors that can promote the successful implementation of DB project delivery systems on Indonesian road infrastructure projects. Four main factors and 28 indicators were identified from an extensive literature review, and a Delphi questionnaire survey was conducted amongst 20 experts drawn from the Indonesian road infrastructure construction sector. The first round Delphi study found that regulation, competency of clients, ability to manage DB projects and external conditions were the major factors that can promote successful DB implementation.

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Public road authorities have a key responsibility in driving initiatives for reducing greenhouse gas (GHG) emissions in the road construction project lifecycle. A coherent and efficient chain of procurement processes and methods is needed to convert green policies into tangible actions that capture the potential for GHG reduction. Yet, many infrastructure clients lack developed methodologies regarding green procurement practices. Designing more efficient solutions for green procurement requires an evaluation of the current initiatives and stages of development. A mapping of the current GHG reduction initiatives in Australian public road procurement is presented in this paper. The study includes the five largest Australian state road authorities, which cover 94% of the total 817,089 km of Australian main roads (not local) and account for 96% of the total A$13 billion annual major road construction and maintenance expenditure. The state road authorities’ green procurement processes and tools are evaluated based on interviews and a review of documents. Altogether 12 people, comprising 1-3 people of each organisation, participated in the interviews and provided documents. An evaluation matrix was developed for mapping the findings across the lifecycle of road construction project delivery. The results show how Australian state road authorities drive decisions with an impact on GHG emissions on the strategic planning phase, project development phase, and project implementation phase. The road authorities demonstrate varying levels of advancement in their green procurement methodologies. Six major gaps in the current green procurement processes are identified and, respectively, six recommendations for future research and development are suggested. The greatest gaps remain in the project development phase, which has a critical role in fixing the project (GHG reduction) goals, identifying risks and opportunities, and selecting the contractor to deliver the project. Specifically, the role of mass-haul optimisation as a part of GHG minimisation was reviewed, and mass-haul management was found to be an underutilised element with GHG reduction potential.

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There is an ongoing level of organizational-wide change (such as empowerment and downsizing) occurring within the Australian health care sector. However, there is a paucity of empirical evidence on how public and nonprofit sector nurses cope with these organizational-wide change initiatives and their consequences on individual and work outcomes. This will be the primary aim of the current paper. To this end, a path model is developed base on an integration of existing theoretical perspectives on occupational stress, change management, and person-organizational fit. Data were collected from 252 public and not-for-profit sector nurses. The path analysis suggests that public and nonprofit nurses experience positive and negative change initiatives. Negative change initiatives resulted in an increase in the level of administrative-related stressors. Nurses with more congruent values report less experience with administrative stressors. As nurses experienced more administrative stressors, they tend to report more job dissatisfaction. Nurses whose values were more congruent during organizational change reported higher level of psychological wellbeing. Nurses who were had higher level of psychological wellbeing were found to have higher job satisfaction, which subsequently led to a higher level of organizational commitment.

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The United Nations Decade of Action for Road Safety (2011-2020) recognises the urgency of addressing global road trauma. Road crashes and attempts to reduce risky driving, including public education campaigns, receive media attention in many countries. In Australia, road fatalities have declined significantly. However, the extent of awareness about this success and of fatalities overall is unclear. A survey of 833 Australian drivers revealed the majority of participants under-estimated fatalities. Unexpectedly, some under-estimates appear based on recollections of media reports. The findings suggest lack of awareness of the extent of road deaths and that, paradoxically, media reports might contribute to underestimations. This represents a major public health challenge. Engaging community support for road safety, relative to other health/safety messages, may prove difficult if the extent of road trauma is misunderstood. Misperceptions about fatality levels may be a barrier to road users adopting safety precautions or supporting further road safety countermeasures.

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Road safety barriers are used to minimise the severity of road accidents and protect lives and property. There are several types of barrier in use today. This paper reports the initial phase of research carried out to study the impact response of portable water-filled barrier (PWFB) which has the potential to absorb impact energy and hence provide crash mitigation under low to moderate speeds. Current research on the impact and energy absorption capacity of water-filled road safety barriers is limited due to the complexity of fluid-structure interaction under dynamic impact. In this paper, a novel fluid-structure interaction method is developed based on the combination of Smooth Particle Hydrodynamics (SPH) and Finite Element Method (FEM). The sloshing phenomenon of water inside a PWFB is investigated to explore the energy absorption capacity of water under dynamic impact. It was found that water plays an important role in energy absorption. The coupling analysis developed in this paper will provide a platform to further the research in optimising the behaviour of the PWFB. The effect of the amount of water on its energy absorption capacity is investigated and the results have practical applications in the design of PWFBs.

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Railway level crossings present an arguably unique interface between two transport systems that differ markedly in their performance characteristics, their degrees of regulation and their safety cultures. Railway level crossings also differ dramatically in the importance they represent as safety issues for the two modes. For rail, they are the location of a large proportion of fatalities within the system and are therefore the focus of much safety concern. For the road system, they comprise only a few percent of all fatalities, although the potential for catastrophic outcomes exist. Rail operators and regulators have traditionally required technologies to be failsafe and to demonstrate high levels of reliability. The resultant level of complexity and cost has both limited their extent of application and led to a need to better understand how motorists comprehend and respond to these systems.

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Over the last three decades neoliberalism has transitioned from occupying the margins of economic policy debate to becoming the dominant approach by governments and their economic advisers, a process that has accelerated with the collapse of the former Stalinist states in Eastern Europe and the Soviet Union. This thesis adopts a Marxist framework for understanding this process, beginning as it did in the realm of relatively abstract philosophical and ideological debate to the permeation of neoliberal values throughout all capitalist institutions, including the state bureaucracy. This necessarily means a focus on the dialectical relationship between the rise of neoliberalism and the shifting balance of class forces that accompanied the success of the neoliberal project in transforming the dominant economic policy paradigm. The extent to which neoliberal reforms impacted on workers and public sector institutions, along with the success or otherwise of traditional working class institutions in defending the material interests of workers will therefore be a recurring theme throughout this body of work. The evidence borne from this research and analysis suggests a major shift in the dialectic of class struggle in favour of the power of capital over labour during the period covered, with the neoliberal age being one of defeat for a labour movement that largely failed to adopt successful strategies for defending itself.

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Social harmony can manifest in many ways. In rapidly motorizing countries like China, a growing area of potential disharmony is road use. The increased ability to purchase a car for the first time and a subsequent increase in new drivers has seen several Chinese cities take unprecedented measures to manage congestion. There is a corresponding need to ensure effective traffic law enforcement in promoting a safe environment for all road users. This paper reports qualitative research conducted with Beijing car drivers to investigate perceptions of unsafe road use, penalties for traffic violations, and improvements for the current system. Overall, the findings suggest awareness among drivers of many of the key risk factors. A perceived lack of clarity in how penalties are determined was identified and drivers in-dicated a desire to know how revenue from traffic fines is used. Several suggestions for improving the current system included school/community education about road risks and traffic law. The rise of private car ownership in China may contribute to a more harmonious personal life, but at the same time, may contribute to a decrease in societal harmony. A major challenge for authorities in any country is to promote the idea of a collective responsibility for road safety (traffic harmony), especially to those who perceive that traffic rules do not apply to them. This is a potentially greater challenge for China as it strives to balance harmony on the road and harmony in the broader society.

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Road traffic crashes have emerged as a major health problem around the world. Road crash fatalities and injuries have been reduced significantly in developed countries, but they are still an issue in low and middle-income countries. The World Health Organization (WHO, 2009) estimates that the death toll from road crashes in low- and middle-income nations is more than 1 million people per year, or about 90% of the global road toll, even though these countries only account for 48% of the world's vehicles. Furthermore, it is estimated that approximately 265,000 people die every year in road crashes in South Asian countries and Pakistan stands out with 41,494 approximately deaths per year. Pakistan has the highest rate of fatalities per 100,000 population in the region and its road crash fatality rate of 25.3 per 100,000 population is more than three times that of Australia's. High numbers of road crashes not only cause pain and suffering to the population at large, but are also a serious drain on the country's economy, which Pakistan can ill-afford. Most studies identify human factors as the main set of contributing factors to road crashes, well ahead of road environment and vehicle factors. In developing countries especially, attention and resources are required in order to improve things such as vehicle roadworthiness and poor road infrastructure. However, attention to human factors is also critical. Human factors which contribute to crashes include high risk behaviours like speeding and drink driving, and neglect of protective behaviours such as helmet wearing and seat belt wearing. Much research has been devoted to the attitudes, beliefs and perceptions which contribute to these behaviours and omissions, in order to develop interventions aimed at increasing safer road use behaviours and thereby reducing crashes. However, less progress has been made in addressing human factors contributing to crashes in developing countries as compared to the many improvements in road environments and vehicle standards, and this is especially true of fatalistic beliefs and behaviours. This is a significant omission, since in different cultures in developing countries there are strong worldviews in which predestination persists as a central idea, i.e. that one's life (and death) and other events have been mapped out and are predetermined. Fatalism refers to a particular way in which people regard the events that occur in their lives, usually expressed as a belief that an individual does not have personal control over circumstances and that their lives are determined through a divine or powerful external agency (Hazen & Ehiri, 2006). These views are at odds with the dominant themes of modern health promotion movements, and present significant challenges for health advocates who aim to avert road crashes and diminish their consequences. The limited literature on fatalism reveals that it is not a simple concept, with religion, culture, superstition, experience, education and degree of perceived control of one's life all being implicated in accounts of fatalism. One distinction in the literature that seems promising is the distinction between empirical and theological fatalism, although there are areas of uncertainty about how well-defined the distinction between these types of fatalism is. Research into road safety in Pakistan is scarce, as is the case for other South Asian countries. From the review of the literature conducted, it is clear that the descriptions given of the different belief systems in developing countries including Pakistan are not entirely helpful for health promotion purposes and that further research is warranted on the influence of fatalism, superstition and other related beliefs in road safety. Based on the information available, a conceptual framework is developed as a means of structuring and focusing the research and analysis. The framework is focused on the influence of fatalism, superstition, religion and culture on beliefs about crashes and road user behaviour. Accordingly, this research aims to provide an understanding of the operation of fatalism and related beliefs in Pakistan to assist in the development and implementation of effective and culturally appropriate interventions. The research examines the influence of fatalism, superstition, religious and cultural beliefs on risky road use in Pakistan and is guided by three research questions: 1. What are the perceptions of road crash causation in Pakistan, in particular the role of fatalism, superstition, religious and cultural beliefs? 2. How does fatalism, superstition, and religious and cultural beliefs influence road user behaviour in Pakistan? 3. Do fatalism, superstition, and religious and cultural beliefs work as obstacles to road safety interventions in Pakistan? To address these questions, a qualitative research methodology was developed. The research focused on gathering data through individual in-depth interviewing using a semi-structured interview format. A sample of 30 participants was interviewed in Pakistan in the cities of Lahore, Rawalpindi and Islamabad. The participants included policy makers (with responsibility for traffic law), experienced police officers, religious orators, professional drivers (truck, bus and taxi) and general drivers selected through a combination of purposive, criterion and snowball sampling. The transcripts were translated from Urdu and analysed using a thematic analysis approach guided by the conceptual framework. The findings were divided into four areas: attribution of crash causation to fatalism; attribution of road crashes to beliefs about superstition and malicious acts; beliefs about road crash causation linked to popular concepts of religion; and implications for behaviour, safety and enforcement. Fatalism was almost universally evident, and expressed in a number of ways. Fate was used to rationalise fatal crashes using the argument that the people killed were destined to die that day, one way or another. Related to this was the sense of either not being fully in control of the vehicle, or not needing to take safety precautions, because crashes were predestined anyway. A variety of superstitious-based crash attributions and coping methods to deal with road crashes were also found, such as belief in the role of the evil eye in contributing to road crashes and the use of black magic by rivals or enemies as a crash cause. There were also beliefs related to popular conceptions of religion, such as the role of crashes as a test of life or a source of martyrdom. However, superstitions did not appear to be an alternative to religious beliefs. Fate appeared as the 'default attribution' for a crash when all other explanations failed to account for the incident. This pervasive belief was utilised to justify risky road use behaviour and to resist messages about preventive measures. There was a strong religious underpinning to the statement of fatalistic beliefs (this reflects popular conceptions of Islam rather than scholarly interpretations), but also an overlap with superstitious and other culturally and religious-based beliefs which have longer-standing roots in Pakistani culture. A particular issue which is explored in more detail is the way in which these beliefs and their interpretation within Pakistani society contributed to poor police reporting of crashes. The pervasive nature of fatalistic beliefs in Pakistan affects road user behaviour by supporting continued risk taking behaviour on the road, and by interfering with public health messages about behaviours which would reduce the risk of traffic crashes. The widespread influence of these beliefs on the ways that people respond to traffic crashes and the death of family members contribute to low crash reporting rates and to a system which appears difficult to change. Fate also appeared to be a major contributing factor to non-reporting of road crashes. There also appeared to be a relationship between police enforcement and (lack of) awareness of road rules. It also appears likely that beliefs can influence police work, especially in the case of road crash investigation and the development of strategies. It is anticipated that the findings could be used as a blueprint for the design of interventions aimed at influencing broad-spectrum health attitudes and practices among the communities where fatalism is prevalent. The findings have also identified aspects of beliefs that have complex social implications when designing and piloting driver intervention strategies. By understanding attitudes and behaviours related to fatalism, superstition and other related concepts, it should be possible to improve the education of general road users, such that they are less likely to attribute road crashes to chance, fate, or superstition. This study also underscores the understanding of this issue in high echelons of society (e.g., policy makers, senior police officers) as their role is vital in dispelling road users' misconceptions about the risks of road crashes. The promotion of an evidence or scientifically-based approach to road user behaviour and road safety is recommended, along with improved professional education for police and policy makers.

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Objective: Comprehensive, accurate information about road crashes and related trauma is a prerequisite for identification and control of risk factors as well as for identifying faults within the broader road safety system. Quality data and appropriate crash investigation are critical in reducing the road toll that is rapidly growing in much of the developing world, including Pakistan. This qualitative research explored the involvement of social and cultural factors (in particular, fatalism) in risky road use in Pakistan. The findings highlight a significant issue, previously unreported in the road safety literature, namely, the link between fatalistic beliefs and inaccurate reporting of road crashes. Method: Thirty interviews (one-to one) were conducted by the first author with police officers, drivers, policy makers and religious orators in three Pakistani cities. Findings: Evidence emerged of a strong link between fatalism and the under-reporting of road crashes. In many cases, crashes and related road trauma appear to go unreported because a crash is considered to be one’s fate and, therefore, beyond personal control. Fate was also implicated in the practice of reconciliation between parties after a crash without police involvement and the seeking and granting of pardon for a road death. Conclusions: These issues represent additional factors that can contribute to under-reporting of crashes and associated trauma. Together, they highlight complications involved in establishing the true cost of road trauma in a country such as Pakistan and the difficulties faced when attempting to promote scientifically-based road safety information to counteract faith-based beliefs.