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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
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    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
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      <title>Uncovering Information Hidden in Crash Narratives: Enhancing Safety Reporting for Pedestrians and Bicyclists in Transit Bus Collisions</title>
      <link>https://rip.trb.org/View/2625593</link>
      <description><![CDATA[Pedestrians and bicyclists are among the least protected road users in traffic environments, disproportionately affected by traffic crashes. In 2022, the National Highway Traffic Safety Administration reported 42,795 traffic fatalities in the United States, including 7,522 pedestrians (18 percent) and 1,105 bicyclists (3 percent). Transit buses were involved in 6,731 crashes in 2022, including collisions with pedestrians and bicyclists. These statistics emphasize the critical safety risks faced by pedestrians and bicyclists, particularly in interactions with transit buses. These interactions often result in severe outcomes due to the physical characteristics of buses and the increased exposure of pedestrians and bicyclists. Despite ongoing improvements in crash reporting, existing datasets lack detailed behavioral and contextual factors that can inform targeted interventions. Structured data alone often fails to capture important elements such as pedestrian/bicyclist distraction, alcohol impairment, pedestrian crossing violations, or unusual crash scenarios. As a result, safety professionals and transit agencies face limitations when developing targeted strategies to reduce injury severity and prevent future incidents. This project addresses these deficiencies by leveraging the rich, crash narrative data in the National Transit Database Major Safety Events Dataset. This project applies advanced artificial intelligence and natural language processing methods, including text mining, topic modeling (Latent Dirichlet Allocation), hierarchical clustering, and contextual analysis, to extract meaningful patterns from thousands of crash narratives involving pedestrians and bicyclists. Initial results from over 5,600 crash narratives demonstrate that 20 distinct crash topics can be identified using topic modeling. These topics represent a wide range of behavioral and situational factors, such as pedestrian and bicyclist distraction, limited visibility, and boarding or alighting incidents. By transforming unstructured text into structured indicators, this project enhances transit safety reporting and provides new insights to inform safety practices for pedestrians and bicyclists involved in bus-related crashes.]]></description>
      <pubDate>Mon, 17 Nov 2025 16:09:53 GMT</pubDate>
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      <title>Causal Factors and Mitigation of Transit Bus Collisions



</title>
      <link>https://rip.trb.org/View/2464330</link>
      <description><![CDATA[Providing safe public transit bus services is a core objective of all public transit agencies, local governments, and the organizations that fund and regulate public transportation. While considerable effort has been made to improve the safety of bus transit services, these efforts have not fully addressed the causal (i.e., underlying) factors of bus collisions. Causal factors may be categorized as primary, root, direct, or contributing factors. Eliminating or reducing these factors could mitigate the likelihood and severity of bus collisions and improve safety performance. 

Data and information are available on public transit bus collisions from a range of sources including the federal government, transit agencies, states, and transit risk and insurance pools. Researchers should be aware that reporting of collision data may be affected by applicable law, litigation, and the apportionment of liability. Additionally, identifying the causes of public transit bus collisions from these data is challenging due to variability in data collection methods and definitional inconsistencies used by transit agencies and accident investigators. This variability complicates efforts to accurately determine causal factors of bus collisions, which is important to developing effective strategies to reduce the likelihood and severity of public transit bus collisions with motorized vehicles, nonmotorized vehicles, pedestrians, and fixed objects. 

Despite the considerable interest in public transit safety, research is needed on the causal factors of public transit bus collisions and effective mitigation strategies.  

The objectives of this research are to (1) identify the key causal factors of public transit bus collisions with motorized vehicles, nonmotorized vehicles, pedestrians, and fixed objects, (2) present practical strategies that can be implemented to mitigate the likelihood and severity of bus collisions, and (3) identify the roles and responsibilities of transit agencies and other relevant stakeholders to improve safety. 

This research may consider the following matters regarding causal factors and mitigation strategies: environmental; human (including bus operators, other vehicle operators, and pedestrians); infrastructure; operating environment; public education and awareness; regulation and enforcement; training, procedures, policies, and reporting requirements; vehicle attributes and performance characteristics; and working conditions.]]></description>
      <pubDate>Tue, 26 Nov 2024 05:42:18 GMT</pubDate>
      <guid>https://rip.trb.org/View/2464330</guid>
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      <title>Moving the Bus Safely Back into Traffic, Phase II</title>
      <link>https://rip.trb.org/View/1324980</link>
      <description><![CDATA[The difficulty experienced by transit buses in moving back into traffic safely from bus pullout bays has become a serious problem due to potential hazards between buses merging from pullout bays and the surrounding traffic. Previous studies have determined the need to closely examine the engineering side of the Yield to Bus (YTB) program and to develop effective countermeasures to address the issue. Phase I of this project focused on the comprehensive literature review, field observation, and data collection of three aspects: bus signing and lighting configuration, road signs, and YTB regulations. The Phase I project has determined the best practices of signing and lighting configurations on the rear of buses and roadside signs to assist transit buses to safely re-enter the traffic stream, and identify the needs for further research to evaluate the recommended countermeasures from Phase I. Specifically, the major recommendations including further research from Phase I for on-bus devices are as follows: (1) conduct a comprehensive data collection for evaluating the latest on-bus YTB Light Emitting Diode (LED) flashing signs on the back of buses, (2) assess safety and operational benefits of on-bus LED flashing yield signs, and (3) develop recommendations and implementation of an effective public awareness program to increase public awareness of YTB laws. In 2004 a crash study was conducted to examine all reported bus crashes during the period of 1998 to 2002 on the State Highway System. The results of this report indicated that 47 percent of all bus crashes were rear end collisions. In an attempt to reduce these types of crashes Phase 1 of this research was proposed and accomplished. Phase I of this research project was completed in November, 2007, which presented a comprehensive overview of the existing signage, lighting configurations, and existing YTB laws that were used to help buses merge back into traffic from bus pull-out bays. General engineering recommendations were developed in these three areas based on the statewide bus operators survey, field observations, and preliminary crash data analysis. The specific countermeasures included the implementation of the latest YTB LED flashing signs on the back of buses and advanced road signs and/or beacons. It is necessary to evaluate recommended countermeasures on moving buses safely back into traffic, as well as to assess safety and operational benefits to transit buses and surrounding vehicles by implementing the recommended countermeasures.]]></description>
      <pubDate>Wed, 01 Oct 2014 02:16:25 GMT</pubDate>
      <guid>https://rip.trb.org/View/1324980</guid>
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      <title>A Qualitative Analysis of Bus Simulator Training on Transit Incidents--A Case Study in Florida</title>
      <link>https://rip.trb.org/View/1228465</link>
      <description><![CDATA[The objective of this research project will be to study the impact of simulator training on transit incidents with a specific focus on Florida public transit agencies. The specific research will be to: (1)Provide a brief history of simulator training in the transit industry; (2)Provide a summary of how simulators are being incorporated into Florida's transit properties; (3)Analyze, track and trend incident data pre and post simulator procurement; (4)Identify the impacts simulator incorporation has on incidents; and, (5)Qualitatively measure those impacts.]]></description>
      <pubDate>Thu, 03 Jan 2013 13:21:32 GMT</pubDate>
      <guid>https://rip.trb.org/View/1228465</guid>
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