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Page 49
Suggested Citation:"Chapter 5 - Conclusions." National Academies of Sciences, Engineering, and Medicine. 2020. Current Practices in the Use of Onboard Technologies to Avoid Transit Bus Incidents and Accidents. Washington, DC: The National Academies Press. doi: 10.17226/25716.
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Suggested Citation:"Chapter 5 - Conclusions." National Academies of Sciences, Engineering, and Medicine. 2020. Current Practices in the Use of Onboard Technologies to Avoid Transit Bus Incidents and Accidents. Washington, DC: The National Academies Press. doi: 10.17226/25716.
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Page 51
Suggested Citation:"Chapter 5 - Conclusions." National Academies of Sciences, Engineering, and Medicine. 2020. Current Practices in the Use of Onboard Technologies to Avoid Transit Bus Incidents and Accidents. Washington, DC: The National Academies Press. doi: 10.17226/25716.
×
Page 51
Page 52
Suggested Citation:"Chapter 5 - Conclusions." National Academies of Sciences, Engineering, and Medicine. 2020. Current Practices in the Use of Onboard Technologies to Avoid Transit Bus Incidents and Accidents. Washington, DC: The National Academies Press. doi: 10.17226/25716.
×
Page 52
Page 53
Suggested Citation:"Chapter 5 - Conclusions." National Academies of Sciences, Engineering, and Medicine. 2020. Current Practices in the Use of Onboard Technologies to Avoid Transit Bus Incidents and Accidents. Washington, DC: The National Academies Press. doi: 10.17226/25716.
×
Page 53
Page 54
Suggested Citation:"Chapter 5 - Conclusions." National Academies of Sciences, Engineering, and Medicine. 2020. Current Practices in the Use of Onboard Technologies to Avoid Transit Bus Incidents and Accidents. Washington, DC: The National Academies Press. doi: 10.17226/25716.
×
Page 54
Page 55
Suggested Citation:"Chapter 5 - Conclusions." National Academies of Sciences, Engineering, and Medicine. 2020. Current Practices in the Use of Onboard Technologies to Avoid Transit Bus Incidents and Accidents. Washington, DC: The National Academies Press. doi: 10.17226/25716.
×
Page 55

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49 Over the past decade, bus collision and fatality rates have followed a generally increasing trend, while bus injury rate trends have slightly decreased. Casualty and liability costs rates have also trended upward over the past decade. Transit agencies around the country are facing the challenges of reducing transit bus collisions and the injuries, fatalities, and liability expenses associated with these collisions. The examination performed for this synthesis and industry experiences reflected in the literature review show that many transit agencies are proactively instituting a number of approaches to address these collisions, including the piloting and use of collision avoidance technologies, such as forward collision warning (FCW), emergency braking, lane departure warning (LDW), and electronic stability control (ESC). To reduce the likelihood of pedestrian collisions while turning, agencies have piloted various technologies that detect vulnerable road users obstructed from the operator’s field of view by the bus’s A-pillar or its turning procedures. These tech- nology applications display warning alerts to pedestrians in the form of flashing lights, audible announcements of possible dangers, or both. Other technologies provide displays in the operator workstation to allow operators unobstructed views of their surroundings. Transit agencies often implement collision mitigation measures, like collision avoidance technology applications, in a holistic manner; the inclusion of additional training, bulletins, and other agency modifications makes it difficult to establish the effectiveness of one countermeasure and report a return on investment from collision avoidance technologies. Additionally, it is challenging to predict the monetary savings associated with reduced near-miss events. The purpose of this study was to document the current practices in the use of the various onboard technologies on transit buses to prevent incidents and accidents, with a primary objective of determining whether these technologies are effective in actual practice. A literature review, a survey of 55 transit agencies (44 respondents), and seven detailed case example inter- views were conducted to report on the state of the practice. The summarized survey responses are representative of 44 various-sized transit agencies from 24 U.S. states and the District of Columbia. When asked specifically about collision avoidance technologies installed on their transit buses, 30 percent of the agencies have implemented some sort of rear bus treatment to mitigate rear-end collisions, and 23 percent have implemented pedestrian warning technology on their buses. Thirty-two percent of the responding agencies have not implemented any type of collision avoidance technology on their transit buses. Among the responding agencies that did procure some type of collision avoidance tech- nology, 46 percent indicated that the transit vehicles were modified at the transit agency by vendor technicians, agency personnel, or both, while 4 percent indicated that the manufacturer prewired the transit bus during final vehicle assembly. C H A P T E R 5 Conclusions

50 Current Practices in the Use of Onboard Technologies to Avoid Transit Bus Incidents and Accidents The most significant barriers to implementation of collision avoidance technologies on transit buses are cost and return on investment concerns, retrofitting challenges, and union or operator resistance. Of the 55 percent of respondent agencies that surveyed their employees for feedback on the collision avoidance technology, 36 percent had mostly positive feedback, 29 percent had mixed reactions, and 14 percent had mostly negative feedback. In terms of vendor agreements, 86 percent of the agreements included terms for trouble- shooting, maintenance, or technical support, while 74 percent did not include any terms for upgrading the technology. The potential for upgrading is an important element, as these technologies are evolving at a rapid pace. Lessons Learned Case example agencies provided a number of lessons learned in reducing transit safety risks using advanced collision avoidance and warning systems. Consistently, agencies share certain qualities and characteristics, including highly functioning safety cultures: • All case example agencies approach safety in a holistic, agency-wide manner, in which multiple approaches are applied to address safety concerns. • While case example agencies reported using many means to identify safety risks, all made use of – Data trend analysis, – Internal safety reviews, – Some form of employee reporting, and – Customer reports/complaints. • All case example agencies showed a proactive commitment to safety through their willingness to pilot various technologies to mitigate or prevent bus accidents and incidents. • All case example agencies emphasized the importance of conducting pilots for enough time to determine if the technology is effective and feasible for the agency, and they urged other agencies to consider the possibility of vehicle interface challenges and delays in equipment installation. • All case example agencies piloted or implemented at least one collision avoidance technology, many of which provide pedestrian detection alerts. • All case example agencies recognized the value of their frontline employees and provided opportunities for employee input concerning the technologies. The literature review, survey responses, and case example experiences highlight additional lessons learned that can be used to guide other public transit agencies when considering any of these technologies. Delays occur along the steps of piloting and implementing a new technology, and agencies may have to modify original project schedules. Case example agencies established that the schedules for procurement, testing, and deployment are often underestimated. They suggested that transit agencies interested in testing or deploying a technology understand that there could be significant delays within each phase of the project. GoTriangle representatives suggested that agencies invest at least 6 months of pilot time and allow bus operators to drive multiple vehicles outfitted with the technology and operate within different operating environments. They suggested that this practice might result in more accurate driver feedback. Agencies may need to negotiate carefully with vendors to ensure that agreements meet agency needs. Some agency representatives characterized vendors as inflexible in their contract- ing requirements. While 86 percent of survey respondents reported that agreements included terms for troubleshooting, maintenance, or technical support, 74 percent reported that those agreements did not include any terms for upgrading the technology. Background research

Conclusions 51 and industry input establish that upgrading is an important element, as these technologies are evolving at a rapid pace. Case example agencies recommended that peer agencies work closely with vendors and negotiate allowances for system upgrades. In addition, they also establish the importance of training bus operators on the technology. Vendors should provide initial training to bus operators or providing train-the-trainer sessions to ensure operators understand the capabilities of the technology, what visual or audible alerts mean, and how an operator can effectively respond. Systems that provide driver alerts can be distracting. The findings from the literature review and responses from a few survey respondents and case example sites suggest that technologies that provide alerts to drivers are often viewed as a distraction. Nevertheless, some studies suggest that the use of “white noise” or verbal alerts rather than beeps or other alarms has been accepted. The Metropolitan Transit Authority of Harris County (METRO) asked technology vendors to use voice announcements in lieu of audible beeping alerts in response to driver feedback. Those technologies that provide audible alerts to vulnerable road users outside the transit bus are often described as a nuisance. Interestingly, one respondent agency stated that it proactively installed a turn warning/collision detection system on its electric buses. Due to the relatively silent running of these buses, the warning system was viewed as a positive approach to ensuring vulnerable road users are aware of turning buses. The interviews with personnel case example transit agencies revealed frustration related to technology vendors that were unable to reduce the number of false positive alerts issued to drivers. False positive alerts are a problem not only because they distract drivers also because of the more significant concern that alerts will be ignored and the risk for collision events increased. This report provides examples of agencies that successfully worked with vendors to reduce the false positives. The literature review and case examples reflect benefits associated with these technology deployments. Several research reports capture the benefits of collision avoidance technologies, both active technologies and those passive systems that provide alerts to bus operator, and onboard camera applications. Following a 2016 collision avoidance warning system pilot coordinated by the Washington State Transit Insurance Pool for its members, it was esti- mated that the total annual net benefits from collision claims reduction due to the technology would increase from $1.1 million in year 5 of the pilot to $2.1 million in year 14. While buses equipped with the system logged 352,129 miles and 23,798 operating hours, they had no collisions with bicyclists or pedestrians during the pilot. In addition, the authors reported a large reduction in near-miss events. Research has also shown that these systems improve operators’ situational awareness and sensitivity to conditions that may trigger a warning. It has been suggested that operators could be conditioned to anticipate and correct triggering conditions, avoiding potential collisions. TCRP Synthesis 123 reported that, as a result of the placement of onboard camera units on buses, claims and litigations against the Southeastern Pennsylvania Transportation Authority (SEPTA) have declined and SEPTA has saved $40 million annually (Thomson, Matos, and Previdi 2016). More advanced camera systems tied to onboard driver monitoring systems are reported to more effectively identify near misses and risky driver behaviors and to be useful as training aids to improve driver skills and reduce risky behaviors. Battelle’s Enhanced Transit Safety Retrofit Package (E-TRP) piloted at the Greater Cleveland Regional Transit Authority (RTA) resulted in an 18.8 percent improvement in operator reaction time and a 16 percent improvement in operators’ responses to pedestrian warnings. While the Battelle E-TRP pilot did not result in any documented cost savings to the agency, the total and preventable collision rates consistently decreased from 2016 to 2018.

52 Current Practices in the Use of Onboard Technologies to Avoid Transit Bus Incidents and Accidents Since 2015, following the installation of the Protran Safe Turn Alert System, SEPTA saw a 54 percent decrease in left-turn pedestrian knockdowns, a 50 percent decrease in right-turn pedestrian knockdowns, and a 41 percent decline in total pedestrian knockdown incidents. SEPTA indicated that these reductions were due not only to the implementation of the system but also to the initiation of its “Bus/Pedestrian Collision Mitigation Program.” Case example agencies note the importance of data tracking and trending. Tracking and trending data to guide the implementation of safety mitigation measures were defined as beneficial by 37 percent of the respondent agencies that provided some sort of model practice. One agency specifically uses hot-spot mapping to identify locations where collisions or near collisions have occurred to allow for focused intervention methods such as ride checks, radar checks, and coaching opportunities. Some respondents mentioned the specific benefits of driver monitoring technologies that activate automatically upon changes in forces due to evasive maneuvering or a collision event. Survey respondents highlighted the value of intervening with targeted refresher training using the data collected from the driver monitoring programs. Additionally, the video collected from these driver monitoring technologies has been reported as beneficial in complaint investigation, contributing to decreased liability payouts. All case example agencies described advanced data collection, monitoring, and safety risk assessment processes within their agencies. A number of those agencies have already begun the organization-wide institution of safety management systems and recognize the necessity for comprehensive, ongoing data collection, analyses, and monitoring in support of safety risk management and safety assurance functions, as well as the prioritization of agency resources to address areas of risk. Many of the technologies used by case example sites and survey respondents generate signi- ficant amounts of data. There are challenges associated with utilizing this data to track and trend alert generating events, causal or contributing factors, and other elements. Some of the most significant challenges involve • The type of data available and how to use data to effectively track performance and safety improvements; • Accessibility of the data if vendors “hold” the data and transit agencies must negotiate the level of accessibility and the data they require; • Storage and server capacity if agencies have access to the data; and • The lack of agency personnel qualified to manage and analyze the data. Some agencies suggested that, when negotiating vendor agreements, agencies must address data accessibility and storage. There are also internal considerations that must be addressed before data generation begins. Safety Risk Assessment Safety risk assessments are a standard practice described by survey respondents and further discussed by each of the seven case example agencies. Assessments were commonly performed utilizing accident reports; employee safety reporting; comprehensive data collection, perfor- mance measurement, and tracking trends; customer feedback and safety reporting; and internal safety reviews. Approximately 50 percent of survey respondents indicated that they identify risks through employee close-call or near-miss safety reporting. Dallas Area Rapid Transit (DART) contracted with a third party to review collision data and accident reports from 500 bus collisions. Based on the analyses and associated recommendations, the agency implemented its Collision Avoidance Countermeasure project. SEPTA, through its

Conclusions 53 robust data collection and analyses processes, identified pedestrian knockdowns as a critical concern. In response, SEPTA utilized a third party to analyze specific pedestrian knockdown incidents and provide recommendations for mitigation alternatives. One recommendation was to reduce the size of the left side mirror on SEPTA buses. This modification resulted in zero knockdown events the year following its implementation. While neither the DART nor the SEPTA examples resulted in the implementation of active collision avoidance technologies, they were reported as highly effective. Additional information on these programs is presented in Appendix C. Greater Bridgeport Transit (GBT) recognized the value of customer complaints in identify- ing areas of safety risk; it therefore investigates customer complaints related to safety concerns using the same methods used to perform accident reviews. These customer complaints related to safety concerns are included as elements of risk and are included in GBT’s risk management processes. Use and Acceptance of Technologies Case example agencies have actively solicited and obtained feedback from their employees on the deployed technologies to gauge acceptance, any issues experienced, and overall useful- ness. In general, many of these agencies have had favorable responses to the technologies. In response to their survey efforts, case example agencies suggested that other agencies gather feedback through multiple distribution methods, as electronic survey forms did not result in high response rates. Several agencies provided suggested methods for increasing survey response rates and gathering more employee feedback on the technologies through alternative means. Methods included providing incentives to those who complete acceptance surveys and estab- lishing focus groups for frontline employees or other transit agency personnel responsible for the operation or maintenance of the vehicles on which technologies were deployed; employees responsible for the maintenance, updating, and troubleshooting of technology hardware or software; and other support employees. Other agencies such as SEPTA gather operator feed- back from direct face-to-face conversations. There are several indications from the literature review, survey responses, and case example participants that the ability to overcome issues with the alerts and false positives generated by these technologies will translate into higher employee acceptance. Survey respondents and case example agencies consistently emphasized the importance of union involvement as soon as logistically possible to gain consensus and buy-in. Constraints and Challenges Survey respondents reported that constraints and challenges associated with the imple- mentation of new technologies include concerns over the costs associated with procuring the technologies; accessing, controlling, and managing the data; and the levels of service and resources provided by vendors. A focus on data flexibility and requesting more data than an agency anticipates will be needed may help to reduce the burden of the data challenges and constraints. Additional challenges and constraints are related to retrofitting transit buses, excessive false negatives and false positives, nonworking equipment or software, and bus operator and union resistance. Survey respondents and case example participants also stated that vendors can be inflexible in their contracting requirements, which can lead to scheduling delays or vendor reselection. In addition, the temporal limitation of pilots means that there may not be enough time to track performance measures in a meaningful way and that there may not be enough data to

54 Current Practices in the Use of Onboard Technologies to Avoid Transit Bus Incidents and Accidents result in statistically significant analyses and findings. A number of survey respondents indicated that it was very difficult to document safety improvements resulting from the technologies, although 47 percent of respondents indicated that they did have documented improvements. DART also discussed the time limitations with pilots or demonstrations, noting that challenges with the installation and initial operability of system hardware and software take time to correct. These time constraints often result in agencies having only a few months of technology testing and evaluation, which they suggested is not enough time to verify the usefulness of the technology. Further Research The topic of transit bus collisions involves many complex variables, many of which could be improved through effective and actionable research and knowledge transfer. The actions of other vehicle drivers (e.g., those operating automobiles, scooters, and bicycles or motorcycles) and pedestrians that result in collisions with transit buses are critical points for investigation. Evaluations of public outreach programs and other strategies designed and implemented to increase the awareness of the public would be helpful. These programs could include those targeted to automobile or other motorized vehicle drivers, pedestrians, and cyclists, cautioning them of the dangers of distraction and other contributing factors that are present in collisions with transit buses. As demonstrated in the Battelle-led pilot at RTA and reflected in the literature review, the increasing ubiquity of connected vehicle and onboard collision avoidance technologies in personal vehicles and current autonomous and connected vehicle pilots in the transit industry show promise in the ever-evolving landscape of available strategies deployed to reduce collisions. Research associated specifically with vehicle-to-vehicle communication between late-model personal vehicles and transit buses would be beneficial. In addition, the industry would benefit from an expanded discussion of the safety aspects of these advanced systems and any associated liabilities. Aside from the need for expanded research related to connected vehicle communication with transit buses, other technologies that are currently incorporated in the personal and commercial vehicle market could potentially benefit transit bus safety as well. The transit bus industry could benefit from additional research on expanding additional applications of collision warning systems and autonomous emergency braking technologies from personal vehicles to transit buses. Because of the lag time associated with air brakes in a transit bus, the increased weight of the bus compared with a personal vehicle, and the additional consideration of forces experienced by the bus passengers, the expansion of automatic emergency braking on transit buses will likely require further research. The industry could benefit from research or model practices on how to improve the acceptance of collision avoidance technologies on transit buses by frontline employees through (1) effective methods to obtain employee feedback and (2) ensuring employee input from the earliest stages, when the agency is considering certain technologies to counter existing areas of risk. Vendors and transit agencies could benefit from additional research to increase the feedback response rates from operators, maintenance technicians, and training personnel to gain a holistic under- standing of the challenges and benefits experienced by the entire agency. The additional research could also include considerations of placebo effects that may be experienced. The synthesis team thoroughly examined and reported vendor negotiation and contracting challenges presented by case example and survey respondents. In summary, the public trans- portation industry would benefit from a comprehensive guidance report, a “how-to” guide,

Conclusions 55 or recommended practices that address the procurement of technologies and the many aspects of technology vendor negotiations and contracting. The suggested guide could focus on performance-based procurement language. The review of APTA’s (2013) “Standard Bus Procurement Guidelines: A Standardized Request for Proposal Contract Form for the Transit Industry” may provide an opportunity to incorpo- rate recently developed and marketed technology features in the suggested request for proposal technical contents. LDW systems have been widely accepted by the personal vehicle market and have led to improved rates of single vehicle and sideswipe collisions (Chiarenza et al. 2018). Transit bus agencies have pushed back on the usefulness of LDW systems given the number of lane changes and pullouts that are typically navigated on a bus route. Inadequate lane widths, however, could be contributing to transit bus collisions with pedestrian, cyclist, and other vehicles; and LDW systems could reduce these incidents. In addition, the industry may benefit from research that examines lane width design standards used by state and local governments and that suggests areas for improvement to effectively accommodate the space requirements for transit buses. There has been considerable research performed on the safety risks associated with direct vision (generally related to field of view) and indirect vision technology limitations identified through the initial literature review for this synthesis project. “Blind spots” and the risks that can contribute to increased collisions with other vehicles, pedestrians, and bicyclists have been the topic of research specifically for heavy-goods vehicles. Transport for London has sponsored a number of these research activities and based part of its Bus Safety Standard on the findings associated with that research (TfL and TRL 2018). While not specifically the focus of this synthesis study on onboard technologies to reduce transit incidents, future research on these vision topics and the identification of associated recommended practices or design elements to mitigate reduced vision would benefit the industry. Finally, further research would help to standardize bus operator workstation designs to eliminate or mitigate issues related to blind spots and to improve drivers’ wellness through, for example, better seat designs (ATU 2017a).

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Transit agencies around the country are facing the challenges of reducing transit bus collisions and the injuries, fatalities, and liability expenses associated with these collisions.

The TRB Transit Cooperative Research Program's TCRP Synthesis 145: Current Practices in the Use of Onboard Technologies to Avoid Transit Bus Incidents and Accidents documents the current practices in the use of the various onboard technologies on transit buses to prevent incidents and accidents, with a primary objective of determining whether these technologies are effective in actual practice.

The examination shows that many transit agencies are proactively instituting a number of approaches to address these collisions, including the piloting and use of collision avoidance technologies, such as forward collision warning (FCW), emergency braking, lane departure warning (LDW), and electronic stability control (ESC).

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