Assessing the 'system' in safe systems-based road designs: using cognitive work analysis to evaluate intersection designs

Advancing traffic safety through the safe system approach: A systematic review

The Safe System Approach (SSA) has emerged as a comprehensive framework for enhancing traffic safety through system-wide interventions. This systematic review, conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, analyzes 82 relevant studies categorized based on the SSA pillars: safe road users, safe vehicles, safe speeds, safe roads, and post-crash care. The review provides insights into SSA's effectiveness in reducing road traffic fatalities and injuries, exploring implementation challenges and opportunities, including policy initiatives, institutional frameworks, and stakeholder collaborations. The findings highlight the potential for SSA to create a more forgiving and resilient transportation system, offering valuable guidance for policy decisions, future research, and interventions aimed at promoting safer road environments. SSA's comprehensive strategy for Safe Road Users encompasses considerations of road system design, behavior modification, and tailored measures for vulnerable users, showcasing its versatility in addressing diverse challenges. In the realm of Safe Vehicles, SSA actively involves manufacturers in a cycle of continuous improvement, rigorous testing, and collaborative efforts to establish new safety regulations. The emphasis on managing Safe Speeds, aligning with human parameters, and involving communities reflects SSA's adaptable nature and provides insights for establishing context-specific speed limits. SSA contributes significantly to Safe Roads through its implementation of innovative countermeasures, forgiving road designs, and the integration of emerging disciplines, resulting in a notable reduction in fatalities and injuries. In the domain of Post-Crash Care, SSA's integrated perspective fosters collaboration among emergency services, medical professionals, and the justice system. It addresses challenges through standardized approaches and information sharing, ensuring a comprehensive and unified approach to road safety. This review contributes to the ongoing efforts to prioritize safety and transform the transportation landscape on a global scale.

Resilient interactions between cyclists and drivers, and what does this mean for automated vehicles?

The road transport system is a complex sociotechnical system that relies on a number of formal and informal rules of the road to ensure safety and resilience. Interactions between vulnerable road users and drivers often includes informal communication channels that are tightly linked to social norms, user expectations and the environmental context. Automated vehicles have a challenge in being able to communicate and respond to these informal rules of the road, therefore additional technologies are required to better support vulnerable road users. This paper presents the informal rules that cyclists and drivers employ within a cyclist overtake manoeuvre, through qualitative data collected from focus groups and interviews with road users. These informal rules are classified into the key elements of resilience (monitor, detect, anticipate, respond and learn) to understand how they guide the resilient interactions between road users. Using a human factors approach, the Perceptual Cycle Model shows how information is communicated between different road users and created by the situational context. This is then used to inform how automation will alter the communication between cyclists and drivers, and what additional feedback mechanisms will be needed to support the systems resilience. Technologies that can support these feedback mechanisms are proposed as avenues for future development.

'Over to you': using a STAMP control structure analysis to probe deeper into the control of UK road safety at a municipal level - the case of Cambridgeshire

The UK has seen little progress in reducing road death over the last decade and as a result, the government has been criticised by industry stakeholders for a lack of leadership, including the removal of national targets in 2011 and the devolution of powers to a municipal level. The aim of this paper is to understand how decision-making at a municipal level takes place from a systems perspective, using the case study of Cambridgeshire. Actors involved were mapped using a STAMP control structure analysis and highlighted a key role for formal and informal partnerships between local and national government agencies and non-government organisations at the same level in the control structure. The changing international context of the model for the UK is also discussed in relation to the UK's withdrawal from the European Union and provides a useful tool for future analysis of its effect on policy and decision-making. Practitioner summary: This paper uses a STAMP control structure analysis to understand how decision-making at a municipal level takes place from a systems perspective, using the case study of Cambridgeshire. It highlights a key role for formal and informal partnerships between organisations at the same level in the control structure. Abbreviations: STAMP: System Theoretic Accident Model and Processes; STAMP-CAST: Systems-Theoretic Accident Model and Processes - Causal Analysis using Systems Theory; FRAM: Functional Resonance Analysis Method; HFACS: Human Factors Analysis and Classification Scheme; NGO: Non-Government organisation; iRAP: International Road Assessment Programme; EuroRAP: European Road Assessment Programme; NCAP: New Car Assessment Programme; CCG: Clinical Commissioning Group; GP: General Practitioner; PPE: Personal Protective Equipment; SD: standard deviation; Beds: Bedfordshire; Cambs: Cambridgeshire; Herts: Hertfordshire; Pboro: Peterborough.

Resolving the differences between system development and system operation using STAMP: a road safety case study in a low-income setting

Road safety strategies adopted worldwide have made significant progress in reducing road trauma, but have stagnated more recently. The situation in low- and middle-income countries is even worse with no significant decrease in fatality rates. Safety researchers have argued that adopting sociotechnical systems approach is necessary to make significant advancements and improvements. The aim of this study was to develop a control structure model of the Bangladesh road safety system by identifying the actors and organisations involved across the system. Expert stakeholders were identified and interviewed, and relevant information was gathered in order to generate the Systems Theoretic Accident Model and Process control structure model. Throughout the analysis of this model, differences in the control and feedback mechanisms of the system were identified, and road safety intervention recommendations were made. Future research should also predict potential risks within the system and propose proactive and preventative countermeasures. Practitioner summary: In this article, a Systems Theoretic Accident Model and Process control structure model of the Bangladesh road safety system is developed, and the involved actors are identified. Based on interviews and workshops with expert stakeholders, differences in the controls and feedback mechanisms in the system were identified, and road safety intervention recommendations were made. Abbreviations: BUET: Bangladesh University of Engineering and Technology.

Many model thinking in systems ergonomics: a case study in road safety

In complexity science, the many models thinking philosophy argues for a multi-method approach to complex problems. This article investigates whether the use of multiple systems ergonomics methods to examine the same problem is useful, or whether using different approaches creates incompatible analyses. Five systems ergonomics analyses of road trauma are examined and their key insights extracted. The extent to which these insights are compatible with one another and can be integrated when attempting to reduce road trauma is assessed. The findings indicate that applying several systems ergonomics methods to the same problem is useful, as multiple insights are developed and deficiencies in one approach are countered by the others. Importantly, the case study demonstrates that the insights gained are compatible and support the development of holistic systems thinking-based interventions. In conclusion it is recommended that a many systems ergonomics model thinking approach be adopted by ergonomists working in complex problem spaces. Practitioner Summary: Many model thinking uses multiple methods to understand complex problems. We explore whether this is beneficial in systems ergonomics. Five models of road trauma, developed using five systems ergonomics methods, are examined. The findings demonstrate that a many model systems ergonomics approach produces a diverse but complimentary set of insights.

Young drivers and their cars: Safe and sound or the perfect storm?

Consistent with the experiences in high-income countries, young drivers remain overrepresented in road trauma statistics in low- and middle-income countries. This article pursues the emerging interest of approaching the young driver problem from a systems thinking perspective in order to design and deliver robust countermeasures. Specifically, the focus of this paper is the cars driven by young drivers. The study of vehicles' characteristics and their interaction with driving behaviour is, more often than not, considered a minor concern when developing countermeasures in young drivers' safety not only in developed nations, but especially in developing nations. Participants completed an online survey containing the 44-item Behaviour of Young Novice Drivers Scale Spanish version (BYNDS-Sp), in addition to providing information regarding their vehicle, any crash involvement, and driving offences. Based on the vehicle model information, the assessment of vehicle safety was conducted for three safety programs (ANCAP, Latin NCAP, U.S. NCAP). Young drivers in Colombia reported a breadth of risky driving behaviours worth targeting in broader interventions. For example, interventions can target speeding, particularly as three quarters of the participants drove small-medium cars associated with poorer road safety outcomes. Moreover, risky driving exposure was highly prevalent amongst the young driver participants, demonstrating the need for them to be driving the safest vehicles possible. It is noteworthy that few cars were able to be assessed by the Latin NCAP (with half of the cars rated having only 0-2 star ratings), and that there was considerable discrepancy between ANCAP, U.S. NCAP, and Latin NCAP ratings. The need for system-wide strategies to increase young driver road safety-such as improved vehicle safety-is vital to improve road safety outcomes in jurisdictions such as Colombia. Such improvements may also require systemic changes such as enhanced vehicle safety rating scales and investigation of the nature of vehicles sold in developing nations, particularly as these vehicles typically contain fewer safety features than their counterparts sold in developed nations.

Interactive mechanism of working environments and construction behaviors with cognitive work analysis: an elevator installation case study

Unsafe behavior is a leading factor in accidents, and the working environment significantly affects behaviors. However, few studies have focused on detailed mechanisms for addressing unsafe behaviors resulting from environmental constraints. This study aims to delineate these mechanisms using cognitive work analysis (CWA) for an elevator installation case study. Elevator installation was selected for study because it involves operations at heights: falls from heights remain a major cause of construction worker mortality. This study adopts a mixed research approach based on three research methodology stages. This research deconstructs the details of the working environment, the workers' decision-making processes, the strategies chosen given environmental conditions and the conceptual model for workers' behaviors, which jointly depict environment-behavior mechanisms at length. By applying CWA to the construction industry, environmental constraints can easily be identified, and targeted engineering suggestions can be generated.

Concurrent audio-visual feedback for supporting drivers at intersections: A study using two linked driving simulators

A large portion of road traffic crashes occur at intersections for the reason that drivers lack necessary visual information. This research examined the effects of an audio-visual display that provides real-time sonification and visualization of the speed and direction of another car approaching the crossroads on an intersecting road. The location of red blinking lights (left vs. right on the speedometer) and the lateral input direction of beeps (left vs. right ear in headphones) corresponded to the direction from where the other car approached, and the blink and beep rates were a function of the approaching car's speed. Two driving simulators were linked so that the participant and the experimenter drove in the same virtual world. Participants (N = 25) completed four sessions (two with the audio-visual display on, two with the audio-visual display off), each session consisting of 22 intersections at which the experimenter approached from the left or right and either maintained speed or slowed down. Compared to driving with the display off, the audio-visual display resulted in enhanced traffic efficiency (i.e., greater mean speed, less coasting) while not compromising safety (i.e., the time gap between the two vehicles was equivalent). A post-experiment questionnaire showed that the beeps were regarded as more useful than the lights. It is argued that the audio-visual display is a promising means of supporting drivers until fully automated driving is technically feasible.

Who is in control of road safety? A STAMP control structure analysis of the road transport system in Queensland, Australia

Despite significant progress, road trauma continues to represent a global safety issue. In Queensland (Qld), Australia, there is currently a focus on preventing the 'fatal five' behaviours underpinning road trauma (drug and drink driving, distraction, seat belt wearing, speeding, and fatigue), along with an emphasis on a shared responsibility for road safety that spans road users, vehicle manufacturers, designers, policy makers etc. The aim of this article is to clarify who shares the responsibility for road safety in Qld and to determine what control measures are enacted to prevent the fatal five behaviours. This is achieved through the presentation of a control structure model that depicts the actors and organisations within the Qld road transport system along with the control and feedback relationships that exist between them. Validated through a Delphi study, the model shows a diverse set of actors and organisations who share the responsibility for road safety that goes beyond those discussed in road safety policies and strategies. The analysis also shows that, compared to other safety critical domains, there are less formal control structures in road transport and that opportunities exist to add new controls and strengthen existing ones. Relationships that influence rather than control are also prominent. Finally, when compared to other safety critical domains, the strength of road safety controls is brought into question.

More than meets the eye: Using cognitive work analysis to identify design requirements for future rail level crossing systems

An increasing intensity of operations means that the longstanding safety issue of rail level crossings is likely to become worse in the transport systems of the future. It has been suggested that the failure to prevent collisions may be, in part, due to a lack of systems thinking during design, crash analysis, and countermeasure development. This paper presents a systems analysis of current active rail level crossing systems in Victoria, Australia that was undertaken to identify design requirements to improve safety in future rail level crossing environments. Cognitive work analysis was used to analyse rail level crossing systems using data derived from a range of activities. Overall the analysis identified a range of instances where modification or redesign in line with systems thinking could potentially improve behaviour and safety. A notable finding is that there are opportunities for redesign outside of the physical rail level crossing infrastructure, including improved data systems, in-vehicle warnings and modifications to design processes, standards and guidelines. The implications for future rail level crossing systems are discussed.