Intolerable Risks Research Articles

Tailings storage facilities in China: historical failure incidents, existing status, and database-driven quantitative risk assessment

Tailings storage facility (TSF) failures in China have historically resulted in downstream consequences, including fatalities, economic harm, and environmental contamination. However, the nation-wide documentation on existing TSFs is incomplete, and the magnitude-frequency statistics of the failures are poorly quantified. These gaps have impeded ongoing efforts of risk assessment and mitigation. This study collates and analyzes new databases on historical TSF failures and existing TSFs in China. We report 143 TSF failures in China over the period 1957-2023, which exceeds the number (∼20) reported in previous studies. Magnitude-frequency statistics indicate that the mean return period for TSF failures in China with at least 10 fatalities is ∼5 years, while for those with released volumes >1 million m3 is ∼16 years. Our review confirms that there are at least 14,217 existing TSFs in China; therefore, the cumulative failure rate of TSFs in China is estimated to be ∼1%. We supply a database of 1,853 TSFs that lists the statistics such as storage volume and dam height. Using these datasets along with downstream demographic statistics, we undertake a regional risk assessment for Jilin Province, which identifies 11 TSFs with intolerable risks. Among these, the most critical TSF poses a potential loss of 175 lives. Our findings provide the most comprehensive picture of TSFs in China to date. We anticipate that this study will advance tailings disclosure practices in China and support screening-level risk assessments by provincial regulators to help prioritize community engagement and risk mitigation efforts.

Neurodiversity and the Neuro-Neutral State

Over the past decade, many philosophers have argued that to respect the moral equality of their citizens, states should be neutral toward certain forms of diversity among their populations. Areas in which the state neutrality has been advocated include, but are not limited to, citizens’ different religions; languages; and sexual orientations. However, there remains an important area where its normative (ir)relevance has not been discussed: That of neurodiversity. After identifying several ways in which contemporary states disfavor the interests of neurodivergent groups relative to the neurotypical majority, including those of autistic people; dyslectic people; and people with ADHD, the most promising would be-justifications for such unequal treatment are considered. They maintain respectively that states only have to be neutral toward differences that feature in people’s conceptions of the good life; that addressing the discussed neuro-inequalities is too costly, whether financially or otherwise; that doing so raises intolerable risks of a public backlash; and that a commitment to neuro-neutrality leads to overinclusion. None are found to be convincing across the board, which leads me to conclude that states should become significantly more neuro-neutral than they are today.

A novel decision support system for proactive risk management in healthcare based on fuzzy inference, neural network and support vector machine

BackgroundThe nature of activities practiced in healthcare organizations makes risk management the most crucial issue for decision-makers, especially in developing countries. New technologies provide effective solutions to support engineers in managing risks. PurposeThis study aims to develop a Decision Support System (DSS) adapted to the healthcare constraints of developing countries that enables the provision of decisions about risk tolerance classes and prioritizations of risk treatment. MethodsFailure Modes and Effects Analysis (FMEA) is a popular method for risk assessment and quality improvement. Fuzzy logic theory is combined with this method to provide a robust tool for risk evaluation. The fuzzy FMEA provides fuzzy Risk Priority Number (RPN) values. The artificial neural network is a powerful algorithm used in this study to classify identified risk tolerances. The risk treatment process is taken into consideration in this study by improving FMEA. A new factor is added to evaluate the feasibility of correcting the intolerable risks, named the control factor, to prioritize these risks and start with the easiest. The new factor is combined with the fuzzy RPN to obtain intolerable risk prioritization. This prioritization is classified using the support vector machine. FindingsResults prove that our DSS is effective according to these reasons: (1) The fuzzy-FMEA surmounts classical FMEA drawbacks. (2) The accuracy of the risk tolerance classification is higher than 98%. (3) The second fuzzy inference system developed (the control factor for intolerable risks with the fuzzy RPN) is useful because of the imprecise situation. (4) The accuracy of the fuzzy-priority results is 74% (mean of testing and training data). ConclusionsDespite the advantages, our DSS also has limitations: There is a need to generalize this support to other healthcare departments rather than one case study (the sterilization unit) in order to confirm its applicability and efficiency in developing countries.

Identifying constraints and limits to climate change adaptation in Austria under deep uncertainty

Although humanity has always been adapting to a changing environment, the accelerated rate of climate change in combination with continued socioeconomic development and the delay in climate action result in deep uncertainties, further challenging policy, and decision making. A main are of concern, triggered by the increasing frequency and intensity of climatic hazards are growing uncertainties regarding the effectiveness of prevailing adaptation strategies, as well as constraints and eventually limits to adaptation. The existing literature is largely conceptual and focusses on the Global South, where evidence for reaching adaptation limits already exists. In this study, we aim to uncover whether Austria, a Global North country, faces intolerable risks from climate change and experiences adaptation constraints that may trigger limits to adaptation. As there are still considerable uncertainties involved in quantifying potential adaptation limits, we use a social science approach to collect first empirical evidence on this crucial issue. We identify and discuss sources of concern based on semi-structured interviews (n = 26) with climate change adaptation and disaster risk management experts. Our results indicate that although Austria may currently not face physical constraints, which could lead to “hard” adaptation limits, it is nevertheless essential to upgrade existing adaptation strategies for more severe climatic events that may impose “soft” adaptation limits at the local and individual level. Many of these perceived soft adaptation limits are linked to constraints in imagination, awareness, and knowledge, but also to confining decision-making processes and the locked-in focus on technical adaptation measures, which cannot be scaled up indefinitely. To overcome these constraints and avoid adaptation limits, we suggest more inclusive stakeholder involvement in adaptive planning and the design of climate strategies by fostering bottom-up or participatory processes and integrating disaster risk management and climate change adaptation more strongly within polycentric risk governance approaches. Our insights can be seen as a precursory scoping study for the establishment of comprehensive decision making under deep uncertainty approaches in Austria and beyond, since at least many Global North countries share similar constraints and uncertainties regarding technological, economic, and political trends.

Social‐ecological systems approach for adaptation to climate change

AbstractAdaptation to climate change has become part of national development programs (e.g., National Adaptation Planning). Though communities are adapting to climate change across the world, this perspective argues that understanding social and ecological systems requires greater attention to enhance resilience for achieving and moving beyond the Sustainable Development Goals (SDGs) in response to climate change across the world. In addition, based on a systematic literature review, this perspective identifies key research gaps and addresses relevant key challenges and future research direction for social and ecological systems (SES) adaptation to climate change. Ultimately, this may also help move from the existing limits to adaptation (intolerable risks through adaptive actions) concept to social‐ecological limits to adaptation and offers an opportunity to integrate adaptation to climate change in development planning by considering both SES.

Gun Laws and Gun Deaths: An Empirical Analysis and Theological Assessment

The current state of gun violence in the United States involves an uneven distribution of firearms’ lethal violence that undermines the common good by creating intolerable risks of gun death for certain communities and certain people. Building on Catholic commitments to the dignity of every human life and the importance of solidarity as a counterbalance to structural sin, this article explains how Catholics can respond to this problematic status quo in a fashion that aligns with their faith convictions. The article draws on empirical data about the correlations between firearm availability and firearm mortality rates both internationally and within the United States to lay the foundation for a more nuanced evaluation of gun control laws, consistent with the expectation that Catholics will engage political life thoughtfully and with prudential judgment.

At last, empirical elicitations of the magnitudes of those risks (and costs!) too small to matter and those too large to abide

Scholars, decision-makers, and pundits have long tossed around words and numbers meant to demarcate those health/safety risks that are too small to matter at all (called, variously, “trivial” or “de minimis” or “insignificant”), or risks that are so large as to be abhorrent (“unacceptable,” “intolerable,” and the like). But there has been nothing approaching a consensus about how large or small these important probabilities are, and worse, there have been no serious attempts to explore these concepts via any carefully-elicited preferences from laypeople themselves. Perhaps even more concerning, the dominant paradigm—cost-benefit analysis (CBA)—requires balancing of (monetized) risks against the costs of controlling them, but the parallel concepts of de minimis costs and intolerable costs have never been formally considered. As a result of these lapses, all attempts to consider equity or justice in the distribution of how risks and costs are borne are an absurdity, despite claims to the contrary. This article reports on a pair of elicitations involving 1350 laypeople. In one elicitation, a careful set of background and contextual explanations and a structured series of questions probed where each subject perceived lifetime excess mortality risk (from involuntary exposure) to become “so small you would not spend a moment thinking about it,” and where it becomes so large that “you would strongly object, as an ethical matter, to ever having to face it.” With a separate sample, we asked the parallel questions with regard to regulatory costs imposed by the government in the name of risk reduction. Although there was significant interindividual variation in responses, the central tendency of each of these four science-policy-values “goalposts” was as follows: (1) de minimis risk—a lifetime excess chance of premature death of 1 in 770,000; (2) intolerable risk—1 chance in 570; (3) de minimis cost—$25 per year; and (4) intolerable cost—$775 per year. These results offer, for the first time, a principled and evidence-based starting point for further refinement of which risks or costs to individuals can/should be disregarded in setting policy, and which must dominate policies regardless of how total “monetized lives saved” and total dollar costs compare to each other when viewed simplistically. We offer several prescriptions for how CBA might change, and how environmental/health/safety policy might improve, to take account of these fundamental thresholds in how risks and costs actually impose burdens on citizens. Both those interventions that impose intolerable costs while only reducing diffuse and trivially small risks, and those failures to intervene (sufficiently) that perpetuate intolerable risks for the sake of avoiding trivial and eminently manageable costs, are inefficient, unjust, and are thus unethical.

Methodology for risk management in dams from the event tree and FMEA analysis

Some studies that analyze the risk of dam failures estimate that between 2016 and 2025 about 30 major tragedies should be expected. Failure records between 1900 and 2014 indicate that there is an average of three ruptures every two years, considering only the failures that were officially registered and investigated. It can be said that the potential for dam failures will be driven by the economy, since cost has been the main variable considered in the design, construction, operation, monitoring and closing plan of these structures. As companies reduce investments in maintenance, risk management and failure prevention, there is an incentive for economic recovery, competitiveness of product value and debt reduction, required by investors. The result has been a decrease in specialized labor, to the point that companies no longer have sufficient knowledge about the engineering and operational skills that apply to tailings and water management. Learning from the dams’ tragedies is practically non-existent, in Brazil and worldwide, leading to catastrophic environmental and social consequences. Failures will occur as long as they are viewed and treated as unpredictable, thereby lacking risk management. The proposed risk management method, presented in this paper, considers the information of inspection and instrumentation, identifying risks from event trees, separately, intolerable, tolerable and acceptable risks. The intolerable risks are conducted for FMEA-type failure analysis, where severe, intermediate and mild failures are assessed. The objective is to enable the development of an assertive and effective action plan for dam safety management.

Emergency assistance in situations of abuse, neglect, and self-neglect: exploring the complexity and challenges

ABSTRACT Health and social care professionals are often called upon to provide emergency intervention without the adult’s consent in situations of abuse, neglect, and self-neglect. Little is known about this process despite implications related to health care costs and individual rights. In this qualitative study, 17 health care professionals with experience enacting emergency legislation in BC were interviewed to better understand what leads to an emergency response and how these professionals carry out their role. Five components emerged in the provision of emergency assistance: assessing intolerable risks, assessing incapability, balancing ethical values, exploring resources, and consulting/collaborating. Attention is drawn to the significance of social location, including age, socio-economic, and Indigenous background for influencing the process, sometimes in unintended ways. The challenges in providing emergency interventions may result in social inequities and delay in providing care at times. The importance of bringing a reflexive and intersectional lens to providing interventions is highlighted.

Safety and risk analysis at railway crossings of north-south Addis Ababa light rail

Purpose Railway-level crossings (RLCs) are the point of intersection between rail and road users and are therefore hotpots of road-rail user conflict and catastrophic collisions. The purpose of this study is to assess the risks associated with RLCs and suggest probable reduction measures. Through questionnaires and visual inspection, the authors identify the safety risks, hazards and hazardous events at some railway crossing of Addis Ababa light rail transit (AA-LRT) north-south (N-S) route. The identified risky events are then categorized based on As Low As Reasonably Practicable (ALARP) principle and generic risk ranking matrix. The authors then examine existing safety management measures at railway crossing and assess the need for additional safety management. Five major crossings on the 16.9 km (10.5 mi) N-S line, starting from Menelik II Square to Kality, were considered for the study. This study is carried out by data collection from about 145 stakeholders and the application of statistical data and risk analysis methods. The major findings of this study and the recommendations for improvement are suggested. Design/methodology/approach The research followed a case study approach. Through questionnaires and visual inspection, the authors identify the safety risks, hazards and hazardous events at some railway crossing of AA-LRT N-S route. The identified risky events are then categorized based on ALARP principle and generic risk ranking matrix. Collected data was then analyzed using SPSS to deduce relationships. Findings The study findings reveal human factors as the greatest cause of accidents, injury or death. About 22% of hazards identified by category are human factors, whereas 20% are because of technical problems. Intolerable risks stand at 42%, whereas the tolerable risks are at 36% according to risk classification results as per the ALARP model. Because the process of risk management is a long-term cycle, its importance should not be missed at any time. Research limitations/implications Because of design considerations of RLCs and the difference in generalized human behaviors for people of a given region, the results are limited to AA-LRT RLCs. This study opens a discourse for detailed evaluations, qualitative and quantitative analysis into the categorized identified hazards. There is also room for additional research into the performance of RLCs aimed at formulating standard necessary features that should be included on RLCs for proper risk control especially in emerging economies. Originality/value The research paper is original and has not been submitted for consideration to other journals.

Risk Analysis for High Pressure Gas Pipeline Construction Schedule

In article authors focus on preparation of construction works schedule for high pressure gas pipeline in urbanized area and implementation of risk analysis in estimation of realistic completion date. In the first step, the pipeline was divided into couple of sections with different construction methods. During evaluation open cut methods, HDD and microtunneling methods were verified and for every approach specific types of risk were identified. Since number of potential risks was significant authors decided to apply the method for ranking the risks and introducing most important potential complications in the construction schedule. After risk identification authors prepared set of impact categories, varying for negligible few days delays to disastrous three months or more delays. Moreover for potential risks a list of probabilities were elaborated to described risk is plausible to happen several times during project execution or is rather likely to occur every couple of similar projects. Combination of sets of possible impacts and sets of probabilities resulted in a project specific risk matrix. Risk matrix was the first tool used for ranking of all risks, especially when regions of intolerable risks and risks requiring mitigation plan were drawn in the matrix. Based on professional literature, and their own experience for every potential risk, authors estimated the risk level. Knowing this in the next step all risks were sorted according to decreasing value of risk level and for risks within intolerable area or within area requiring emergency back-up plan. Authors verified if those plausible risks indeed require a schedule reserve or some other solution may be applied. If schedule reserve was a reasonable solution the relevant additional construction time was estimated, having in mind the schedule impact level of reviewed risk. In the end construction schedule was prepared, which includes the risk analysis for all construction methods.

Risk Assessment and Governance Strategy of Production Safety Accidents in Jinwan District of Zhuhai City—Based on Integrated Application of Risk Matrix and Borda Count Methods

Based on the literature research and the actual situation of investigation in Jinwan district of Zhuhai city, the risk factors of production safety accidents in Jinwan district of Zhuhai city were constructed, and the risk factors of production safety accidents are divided into 6 secondary indicators and 20 tertiary indicators. According to the risk matrix formula, the risk levels of production safety accidents in Jinwan district of Zhuhai city are evaluated from the two aspects of occurrence probability and consequence severity, and further ranked by the Borda count method. The results show that road traffic accidents, construction accidents, fire accidents, network and information security incidents, maritime traffic accidents and heavy pollution weather are intolerable risks. Finally, this paper puts forward the risk governance strategy from the aspects of advancing the construction of rule of law, strengthening responsibility, enhancing the investigation and rectification of the risk, improving emergency rescue capabilities and consummating the support safeguard system.

Managing risks in public-private partnership formation projects

While sourcing by means of Public-Private Partnerships has been lauded over recent years, increasingly risks appear to jeopardise public organisations' unique societal tasks. Integrated Risk Management has not yet been applied to public organisations getting involved in PPP in the sense of understanding risk management capabilities. This article explores risk awareness and risk management practices underpinning maintenance partnership formation by means of a dual case study of two PPP projects and a short industry survey. The results suggest that organisations face several “intolerable risks” linked to project governance and project management responsibilities: insufficient representation of qualified employees, absence of a shared performance system, assignment of responsibilities and decision-making authority, impractical or inappropriate partnership agreement, and timing of the partnership initiative. Cross-case analysis revealed the role of different levels of risk awareness and senior management involvement. Drawing on these findings, a framework for risk management for PPP formation projects is developed.

A Study on FSA Application to PRS for Safe Operation of Dynamic Positioning Vessel

The Formal Safety Assessment (FSA) is a structured and systematic methodology developed by the IMO, aimed at assessing the risk of vessels and recommending the method to control intolerable risks, thereby enhancing maritime safety, including protection of life, health, the marine environment and property, by using risk analysis and cost-benefit assessment. While the FSA has mostly been applied to merchant vessels, it has rarely been applied to a DP vessel, which is one of the special purpose vessels in the offshore industry. Furthermore, most of the FSA has been conducted so far by using the Fault Tree Analysis tool, even though there are many other risk analysis tools. This study carried out the FSA for safe operation of DP vessels by using the Bayesian network, under which conditional probability was examined. This study determined the frequency and severity of DP LOP incidents reported to the IMCA from 2001 to 2010, and obtained the Risk Index by applying the Bayesian network. Then, the Risk Control Options (RCOs) were identified through an expert brainstorming and DP vessel simulations. This study recommends duplication of PRS, regardless of the DP class and PRS type and DP system specific training. Finally, this study verified that the Bayesian network and DP simulator can also serve as an effective tool for FSA implementation.

Quality of greywater treated in biochar filter and risk assessment of gastroenteritis due to household exposure during maintenance and irrigation.

This study evaluated treatment of greywater (GW) by a biochar filter in Jordan and assessed the annual risks of infection (Pi-annual ), annual risk of disease (Pd-annual ) and disease burden (in disability-adjusted life years; DALYs) of gastroenteritis caused by Salmonella spp. and rotavirus due to ingestion of GW during system maintenance and consumption of green onions irrigated with treated and nontreated GW. The biochar filter efficiently removed 93% of biochemical oxygen demand (BOD5 ) and 85% of solids, while removal of Escherichia coli was insignificant. Treatment of GW decreased the median Pd-annual due to ingestion of GW from 1·39×10-2 to 6·0×10-3 for Salmonella spp. but did not affect Pd-annual caused by rotavirus (9·73×10-1 to 1·0). Consumption of onions irrigated with treated GW had a median Pd-annual of 1·25×10-9 to 1·2×10-8 for Salmonella spp. and 4·96×10-4 to 4·37×10-3 for rotavirus infection, which was 99·9 and 90% lower, respectively, than the risk when consuming onions irrigated with nontreated GW. The highest risks of gastrointestinal disease were thus associated mainly with direct ingestion of GW when maintaining the system. Garden produce irrigated with GW treated in biochar filter did not display intolerable risks of rotavirus-based gastroenteritis during summer season in the study area given that the produce is harvested 1 to 2days, and washed, before consumption. This study contributes to scientific-based knowledge on the suitability of biochar filters for onsite greywater treatment and confirms the microbial safety of recycling treated greywater for garden irrigation.

Medical complications during pregnancy and childbirth in women with SCI in Switzerland.

A retrospective interview study of mothers with spinal cord injuries (SCIs) who gave birth over the last 15 years. To identify the medical complications of women with SCIs during pregnancy and childbirth in Switzerland and to describe how they dealt with these complications. Swiss Paraplegic Research in Nottwil, the University of Lausanne and participants' homes. Data were collected by self-reported questionnaires and descriptive analysis was conducted. Seventeen women with SCIs who gave birth to 23 children were included. Thirteen of the women were paraplegics and four were tetraplegics. All of them practiced an independent bladder management. Three women changed their bladder management techniques during pregnancy. Five women reported an increased bladder evacuation frequency during pregnancy, and six women reported a new onset or increase in incontinence. We observed no significant increase in bowel dysfunction or skin breakdown due to their pregnancies. Ten women were hospitalised during the course of their pregnancies. Aside from urinary tract infections/pyelonephritis, women were hospitalised for falls, hypertension, pneumonia, preeclampsia, pre-term labour or tachycardia. The results of our study clearly demonstrated that, although medical complications are not infrequent during pregnancy in women with SCIs, pregnancy and delivery in this group of women are possible without posing intolerable risks to the mothers or the children. Urological problems seemed to be the most frequent complication during pregnancy.

Safety risk modeling and major accidents analysis of hydrogen and natural gas releases: A comprehensive risk analysis framework

The potential safety risk of hydrogen production is often the most important element to achieve authority approval and public acceptance. Safe application of hydrogen, especially in a large scale, will require adopting adequate risk control, which requires investment on reliable risk analysis methodology. In the present study, first of all, a reliable and comprehensive safety risk analysis methodology was developed for a hydrogen production plant in an oil refinery, that consists of two qualitative methods: Hazard and Operability (HAZOP) and Preliminary Risk Analysis (PRA), a hybrid method: Event Tree Analysis (ETA) and a quantitative method: Quantitative Risk Assessment (QRA) along with a risk and consequence simulator. A HAZOP study along with the PRA technique was used for determining main hazardous sources and carrying out a qualitative risk analysis. The incident outcomes of the identified high risk scenarios were modeled using the PHAST 6.7 simulator and the frequencies of the initial events and incident outcomes were calculated using risk assessment data directory of International Association Oil & Gas Producers (OGP) and ETA, respectively. Finally, the vulnerability areas of the incident outcomes were determined and the societal risk of hydrogen plant was shown using a ‘Frequency vs. Number of fatality’ graph, known as ‘F–N’ curves. The findings show that the maximum vulnerability distance is caused by the vapor cloud explosion (280 m, at 0.01 bar) and the jet fire (275 m, at 4 kW/m2), respectively. The societal risk of the plant fell in the As Low As Reasonable Practical (ALARP) and intolerable regions according to the F–N curve of UK HSE (Health, Safety Executive) The reformer were the highest and the heat exchanger was the lowest contributor to the total risk. Therefore, the ALARP principle should be applied to indicate the appropriate ways to reduce risks and, for the intolerable risks, the system must be modified structurally, functionally, or organizationally.

Investment into Human Risks in Railways and Decision Optimization

ABSTRACTThe Life Quality Index (LQI) is a rational way to establish a relationship among the resources utilized to improve human safety and the expected fatalities that can be avoided by safety improvement. This article uses the LQI approach to quantify the social benefits of a number of safety management plans for a railway facility such as level crossing (LC). We apply influence diagrams (IDs), which are the extensions of Bayesian Networks, to model and assess the life safety risks. In IDs, problems of probabilistic inference, economics-based utility values, and decision alternatives are combined and optimized. The optimal decision, which maximizes total benefits to society, is obtained for the LC. As low as reasonably practicable (ALARP) case, and is a widely accepted risk acceptance criteria in the railway industry. According to the ALARP, there exists a so-called tolerable region between the regions of intolerable and negligible risks. In the tolerable region, risk is undertaken only if a benefit is desired. To quantify socioeconomic benefits, one needs to have an additional risk acceptance criterion such as LQI. In this article we apply and discuss the advantages of the LQI and the IDs for a number of safety management plans for railway LCs.

Hazard Identification & Risk Assesment in New Chassis Assembly Line

Chassis assemblies in any automobile industries are vulnerable to several hazards. In order to reduce the hazards we need to study and carry out Hazard Identification & Risk Assessment in New Chassis assembly to provide engineering solutions for preventing Accidents / dangerous occurrences and to evaluate the Risk. We have conducted many inspections and observation in the chassis assembly of an automobile industry. From our observations and findings we identified nearly 20 intolerable risks in the chassis line, for which the intolerable risks are converted into tolerable through small projects and those which cannot be converted are reduced through Safe Job Procedures (SJP). All the significant risks are controlled by Occupational Health & Safety Management Program, Standard operating procedures & Operation Control Procedure. From the project, the hazard is minimized or eliminated which ensures safety in the assembly line as well as the safety of workers.

Road Safety Benefits from Bus Priority

The provision of bus priority is often a major consideration in on-street bus rapid transit design. However, the research is limited and suggests mixed outcomes. This paper explores the impact of bus priority treatments on road safety. An empirical analysis of accident data about bus rapid transit routes in Melbourne, Australia, was conducted. The analysis included an aggregate crash frequency analysis that accounted for statistical effects and a disaggregate analysis that used a safety audit and review of accident types. Overall, bus priority treatments reduced accidents, with a statistically significant reduction of 14.0%. The number of fatal and serious incidents dropped considerably (42 to 29 per annum). The disaggregate safety audit showed reductions in intolerable risks, but some concerns such as interaction of buses and traffic at bus lane setbacks (section of a curbside lane where traffic may enter to make a turn as the bus lane reaches an intersection) and greater pedestrian road-crossing distances caused by bus lanes. However, disaggregate analysis of accident type suggested that bus lanes act as a roadside buffer, reducing collisions with roadside objects and other vehicles. The shifting of stopping buses from the traffic lane into a bus lane was shown to reduce accidents. Bus lanes were thought to increase sight distances at unsignalized intersections and consequently reduce accidents with vehicles to the side. Some treatments were thought to increase traffic density, creating safety benefits through slowed traffic. These findings were statistically robust and suggest that a new perspective on planning for and justifying bus priority measures is warranted.