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Shared Use: Progress and Evolution 79 ator of the shared-track demonstration can take to reduce risk. These parameters are summa- rized here. Recognized Risk Factors Accident rate variability with volume and type of rail traffic. Frequency, nature and proximity of freight traffic. Single or double tracks, yard operations. Operating speeds of the light passenger rail equipment. Consider secondary collisions (effects on standees is a particular concern). Reduced fire hazard from less fuel and improved protection for the fuel tank on typical DMU equipment. The number of cars in the consist. Collision effects on the articulated joint. Collision effects on power module or propulsion components. Number of grade crossings, volume and nature of highway traffic. Potential Risk Reduction Measures Upgrade the track maintenance class to reduce the likelihood of a derailment. Lower the operating speeds of freight. Time of day track restrictions. Add intrusion detection and other hazard detection devices. Failsafe train separation. Protection from freight siding roll-outs. Automatic train protection. Grade crossing warning system technology. Extremely high braking rates and redundancy of brake system on DMUs and LRVs. Well developed operating rules and procedures with training and enforcement program. Provision of CEM design including frangible and crush-zone elements in vehicle, in addition to interior features that offer more impact attenuation for passengers. Ultimately, equivalent safety drives mitigation of risk. Risk reduction alternatives may involve federal compliance with negative cost or operational impacts, or adoption of systems that alle- viate specific hazards and reduce risk to levels consistent with those attained via regulatory com- pliance. To achieve a practical demonstration project of concurrent shared-track operations under the federal waiver paradigm: 1. Equivalent safety needs a precise and widely accepted definition that has an objective mean- ing to policymakers and technical staff; and 2. Risk mitigation measures should be quantifiable in the context of a shared-track environ- ment. These "adjustment" factors should be acceptable to a consensus of technical experts. Currently, risk assessment has been applied directly and exclusively to the rail mode, rather than comparing the results to other travel modes that would be used in absence of a shared-track system. Certainly planners and transportation specialists would like to know if relative risk increases or decreases, as a result of their plans. Further tests and demonstrations to gather technical information are critical for validation of risk assumptions, and provide experience in selecting systems, equipment, and operating prac- tices that contribute to a safe, concurrent shared-track environment. Data Collection Plan A demonstration project aims to achieve two goals: to explain the proposed technology to gov- ernment officials and the public at large and to collect data about the technology that will inform