Using the decision ladder to understand road user decision making at actively controlled rail level crossings

A New Form of Train Detection as a Solution to Improve Level Crossing Closing Time

The critical points on the rail and road network are their intersections, i.e., level crossings. During a train crossing, car traffic is stopped. This reduces the fluidity of traffic on the road and, consequently, can cause congestion. The problem increases with the number of cars and trains. Frequently, due to national regulations, level crossing closure times are long. It is mainly dictated by safety issues. Building two-level intersections is not always a good solution, mainly because of the high cost of implementation. In the article, the authors proposed the use of sensors to reduce level crossing closure times and improve the Level of Service on the road network. The analyzed railroad lines are local agglomeration lines, mainly due to safety (low speed of commuter trains) and high impact on the road network. The sensors proposed in the article are based on radar/LIDAR. Formulas similar to HCM methods are proposed, which can be implemented in a railroad crossing controller. Simulations using the PTV Vissim program are carried out and the results are worked out based on the obtained data. The considered method can reduce the level crossing closure time by 68.6%, thereby increasing the Level of Service on roads near railroads.

Factors reducing the detectability of train horns by road users: A laboratory study

Level crossing safety is a well-researched safety issue worldwide, but little attention has been placed on the safety benefits of using train horns when a train approaches a level crossing. Given train horns' adverse effects on the health and well-being of residents living near rail tracks, the use of train horns must be beneficial to safety. The current study sought to determine in a laboratory environment whether road users (N = 31) can detect the range of train horns observed in Australia in terms of loudness and duration, using high-definition audio recordings from railway crossings. A repeated measures design was used to evaluate the effects of key factors likely to influence the detectability of train horns, including, visual and auditory distractive tasks, hearing loss and environmental noise (crossing bells). Train horn detectability was assessed based on participants' accuracy and reaction times. Results indicated the duration of the train horn had the most influential effect on the detectability of train horns, with short-duration train horns less likely to be detected. The presence of bells at a crossing was the second most important factor that limited train horn detection. Train horn loudness also affected detectability: faint blasts were less likely to be noticed, while loudest blasts were more likely to be noticed. However, loud horns reduced the ability to detect the side from which the train was approaching and may result in longer times to detect the train, in the field. The auditory distractive task reduced the train horn detection accuracy and increased reaction time. However, the visual distractive task and medium to severe hearing loss were not found to affect train horn detection. This laboratory study is the first to provide a broad understanding of the factors that affect the detectability of Australian train horns by road users. The findings from this study provide important insights into ways to reduce the use and modify the practice to mitigate the negative effects of train horns while maintaining the safety of road users.

Understanding the systemic influences on maritime pilot decision-making

Maritime incidents occurring during pilotage are of international concern. Maritime pilots control most pilotage operations worldwide, yet despite the safety criticality of their role, research examining pilot decision-making processes during these complex and dynamic operations is scarce. This article describes the findings from two studies that utilised an integrated systems thinking framework to understand how pilots make decisions and what factors are perceived to influence their decisions. Interviews were held with 22 pilots (Study 1) and 17 maritime safety stakeholders (Study 2) in the New Zealand maritime context. The findings illustrate the challenges pilots face during pilotage and provide insights into their decision-making processes and the systemic factors that can be addressed to improve maritime safety. Given the multiple causal pathways to incidents occurring during pilotage identified by this research, it is suggested that multiple systems-wide interventions are needed, which is likely to require a long-term, strategic approach.

Safety and associated parameters influencing performance of rail road grade crossings: A critical review of state of the art

INTRODUCTION

Railroad grade crossings (RRGCs) have emerged as critical transportation infrastructures from the point of safety and operational aspects because two modes of transportation intermingle at the intersecting zone; the understanding of safety and traffic operation at RRGC is of prime concern while planning and designing this transportation facility.

METHOD

In this context, this work tries to comprehend RRGC performance-related parameters from published literature and figure out critical gaps. An international synthesis on the identified potential parameters influencing the RRGC performance (i.e., safety, driver behavior, and operational impact) was carried out by critically reviewing the articles published worldwide. Furthermore, key findings, used variables, analysis methods, research gaps, and recommendations were studied.

RESULTS

The review revealed that many researchers had explored the driver behavior and safety aspect based on past crash data and violations prevailing at RRGC. However, little research has been done to evaluate the effect of highways' operational characteristics on the performance of RRGC. Moreover, limited investigation has been carried out to understand the dilemma of drivers and the proactive safety evaluation of pedestrians and non-motorized vehicles at RRGC. A total of seven critical research gaps concerning parameters are recognized, facilitating a clear agenda for further research pertaining to RRGC performance.

Loud and clear? Train horn practice at railway level crossings in Australia

The road environment has changed markedly over the years. Train horns are ostensibly used to alert road users and are typically mandatory on approach to railway level crossings. However, they have increasingly been seen as a nuisance. Beyond their negative aspects, a study has yet to comprehensively evaluate train horn effectiveness and understand if they remain beneficial and relevant in the contemporary environment. Hence, this study aimed to provide evidence on the actual use of train horns. Field observations were conducted at 54 railway crossings across four Australian States. The effects of level crossing type, location, and environmental conditions were investigated in relation to train horn loudness as objectively measured at the crossing. Results revealed that train horns were not always used, presenting an issue for passive level crossings. However, when sounded, train horn use was redundant and insufficiently loud at level crossings equipped with bells. Taken together, current train horn practice was found to be highly variable and dependent on crossing type, remoteness, and individual train drivers, thus resulting in inconsistent warnings and raising important implications for standardisation.

Modelling and supporting flight crew decision-making during aircraft engine malfunctions: developing design recommendations from cognitive work analysis

In this article, we analyse flight crew response to an in-flight powerplant system malfunction (PSM) using control task analysis. We demonstrate the application of the decision ladder template and the skills, rules, and knowledge (SRK) framework to this new area of inquiry. Despite the high reliability of turbofan engines, accidents and incidents involving PSM still occur. During these unusual events, flight crew have not always responded appropriately, leading to a reduction in safety margins or disruption of operations. This article proposes recommendations for technological and information system that can support flight crew in responding safely and appropriately to a PSM. These recommendations focus on new ways in which information from engine health monitoring system and other sources of data can be utilised and displayed. Firstly, we conducted knowledge elicitation using Critical Decision Method (CDM) interviews with airline pilots who have experienced real or simulated PSM events. We then developed generic decision ladders using the interview data, operations manual, training manual, and other guideline documents. The generic decision ladders characterise the different stages of responding to PSM identified as part of the research. These stages include: regaining and maintaining control of aircraft, identifying PSM and selecting appropriate checklists to secure the engine, and modifying the flight plan. Using the decision ladders and insights from the CDM interviews, we were able to identify cognitive processes and states that are more prone to errors and therefore more likely to generate an inappropriate response. Using the SRK framework, we propose design recommendations for technological and information systems to minimise the likelihood of such inappropriate response. We conclude that this combination of methods provides a structured and reliable approach to identifying system improvements in complex and dynamic work situations. Our specific contributions are the application of these techniques in the unrepresented area of flight operations, and the development of evidence-based design recommendations to improve flight crew response to in-flight powerplant system malfunctions.

Frustration at congested railway level crossings: How long before extended closures result in risky behaviours?

Drivers' non-compliance with rules is a prominent factor in collisions with trains at railway level crossings. Road user impatience and frustration has been identified as an underlying factor in non-compliance and can be characterised as a specific risk factor. However, research on non-compliance related to waiting times and driver inconvenience lacks in the literature. This paper, therefore, seeks to enhance the currently limited understanding of the relationship between waiting times and risky driver behaviour. An Advanced Driving Simulator was used to obtain objective measures of level crossing non-compliance. Subjective measures on driver frustration and decision-making processes were also collected. Sixty participants completed six driving tasks each, with the tasks varying in terms of traffic conditions, number of trains and associated waiting times. This study shows that increased waiting times result in higher levels of frustration and an increased likelihood of risky driving behaviour, particularly for waiting times longer than 3 min. Non-compliance included entering the activated crossing before boom gates are down, entering the crossing after the train passage but before signals are deactivated, stopping/reversing on the crossing. Subjective data revealed that participants did not comply with level crossing rules due to factors including time pressure, impatience/frustration and low perceived risk. The results suggest that, where possible, waiting times should be standardised at values lower than 3 min to reduce the likelihood of risky road user behaviour.

Ending on a positive: Examining the role of safety leadership decisions, behaviours and actions in a safety critical situation

Safety leadership is an important factor in supporting safe performance in the workplace. The present case study examined the role of safety leadership during the Bingham Canyon Mine high-wall failure, a significant mining incident in which no fatalities or injuries were incurred. The Critical Decision Method (CDM) was used in conjunction with a self-reporting approach to examine safety leadership in terms of decisions, behaviours and actions that contributed to the incidents' safe outcome. Mapping the analysis onto Rasmussen's Risk Management Framework (Rasmussen, 1997), the findings demonstrate clear links between safety leadership decisions, and emergent behaviours and actions across the work system. Communication and engagement based decisions featured most prominently, and were linked to different leadership practices across the work system. Further, a core sub-set of CDM decision elements were linked to the open flow and exchange of information across the work system, which was critical to supporting the safe outcome. The findings provide practical implications for the development of safety leadership capability to support safety within the mining industry.

To stop or not to stop: Contrasting compliant and non-compliant driver behaviour at rural rail level crossings

Many rail level crossings (RLXs) have only passive protection, such as static signs instructing road users to stop, yield, or look for trains. Stop signs have been suggested as a low-cost option to improve safety at passive RLXs, as requiring drivers to stop should encourage safe behaviour. However, field observations have noted high rates of non-compliance at stop-controlled RLXs. To explore this further, we conducted an on-road study to identify factors that influence compliance at stop-controlled RLXs. Twenty-two drivers drove a 30.5km route in rural Australia, encompassing three stop-controlled RLXs. In over half of all cases (59%) drivers stopped completely at the RLX; on 27% of crossings drivers executed a rolling stop, and on 14% of crossings drivers violated the stop controls. Rolling stops were defined as a continuous deceleration to <10km/h, but remaining above 0km/h, before accelerating to >10km/h. Behavioural patterns, including visual checks and decision-making, were similar when comparing drivers who made complete versus rolling stops. Non-compliant drivers did not differ from compliant drivers in approach speeds, but spent less time visually checking for trains. Post-drive interviews revealed some drivers wilfully disregarded the stop sign, whereas others did not notice the stop sign. Those who intentionally violated noted trains were infrequent and suggested sight distance was good enough (even though all crossings had been formally assessed as having inadequate sight distance). Overall the results suggest most drivers exhibit safe behaviour at passive RLXs, but a notable minority disregard or fail to notice signs. Potential avenues for redesigning passive RLXs to improve safety are discussed.

Applying an extended theory of planned behavior to predicting violations at automated railroad crossings

Based on an extended Theory of Planned Behavior (TPB, Ajzen, 1985, 1991), we conducted surveys in order to explain and predict violations at a railroad crossing, among pedestrians (n=153) and car drivers (n=151). Measures were made with respect to three chronologically related railroad crossing situations that varied in risk level. The situations were described in scenarios and depicted on photographs. The participants were recruited in the suburbs of Paris, at two automated railroad crossings with four half-barriers. We found that the pedestrians had stronger crossing intentions than did car drivers, especially at the more congested crossing of the two under study. For both categories of road users, intentions and the amount of intention variance explained by the extended TPB factors decreased significantly with risk level. In the most dangerous situations, risk-taking was the most unlikely and the least predictable Self-reported past frequency of crossing against safety warning devices was the main predictor of the intention to commit this violation again, especially among males, followed by the attitude and the injunctive norm in favor the violation. Moreover, car drivers were influenced in their crossing intentions by the descriptive norm. The presence of another vehicle on the tracks when the safety warning devices were activated was perceived not as facilitating, but as an additional risk factor. The discussion addresses the importance of taking into account these determinants of violations in conceiving countermeasures. Our findings could be especially useful for conceiving risk-communication campaigns.