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80 Shared Use of Railroad Infrastructure with Noncompliant Public Transit Rail Vehicles: A Practitioner's Guide the direction of technological research and development, and investment decision making. Any demonstration project should include a data collection plan and consider collecting an exten- sive set of cost and operating data. Key to the success of the demonstration project and for shared-track proponents in general is statistics confirming that risks to passengers in shared-track installations are no higher than a comparable conventional commuter rail system. In addition to the standard federal and state requirements on incident reporting, the demonstration project should collect statistics about inci- dents on shared-track lines with the goal of making a general safety case for this method of oper- ations in the future. Control center databases and vehicle event recorders can provide some of the raw data. Among the key events to record are: Train control technology failures, including failsafe events and any events that do not fail safe or where some other active intervention is required to prevent an incident. Incidents prevented (i.e., accidents averted) by the signal system. Other near-misses where an incident was prevented by mechanisms other than the train con- trol system (and whether the incidents might have failed-safe had the other mechanism not functioned). Standard statistics on passenger injuries, fatalities, and property damage if any accident should occur. Post-accident analysis of vehicles and systems should be carried out to identify any les- sons learned. Grade crossing incidents, particularly actual vehicle strikes that result in railcar damage and grade crossing incidents where the enhanced braking rate of light rail vehicles is successful in preventing a collision, or instrumental in limiting injuries or damage. Detailed operating statistics such as mileages and operating hours should be kept, such that accident rates could be normalized against any number of standard denominators. Suggestions for Demonstration Projects It is recommended that the shared-track transit systems currently operating in San Diego and Southern New Jersey be designated as demonstration systems for the development and promul- gation of the American approach to shared-track transit operations. The transit systems in the two cities represent two different approaches to the safe management of concurrent shared-track operations on opposite coasts of the nation. San Diego Trolley, Inc. The older San Diego system has developed a tightly scripted manual track warrant based approach to allow freight trains at the end of their diurnal period to operate on tracks connected and adjacent to tracks used by light rail cars at the start of the passenger service day. The system does not feature any technologies that ensure fail-safe train separation. The 25-year-old system ran concurrent freight and passenger operations successfully on shared track for the first decade of its operation before such practices were outlawed by federal regulation. Present investments in technologies and specialized infrastructure to ensure fail-safe train separation on the lines are modest. The organizational culture of the line is dominated by transit perspectives, in that San Diego Trolley is designed and operated as a traditional U.S. light rail transit system. Procedures and technologies for monitoring and controlling train movements do not strictly conform to standard U.S. railway operating practices. San Diego presents an opportunity to explore how existing shared-track systems can be upgraded with investments in technology and management systems to backstop the manual pro- cedures presently used for very limited concurrent operations. This should lead to the imple- mentation of management techniques and control systems that allow light rail and freight trains