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59 C H A P T E R 7 Introduction This chapter describes vehicle-based treatments that improve safety at the platform/vehicle interface. The treatments include the use of the following: ⢠Door threshold extensions ⢠Movable vehicle-based gap fillers ⢠Vehicle-based ramps and bridging plates ⢠Vehicle-based between-car barriers ⢠Door closure detection technologies The vehicle-based treatments are technologies that are installed on the vehicle and fill in the space between the door threshold and the platform. Examples shown are from the United States and Germany. Door Threshold Extensions One of the most common vehicle-based treatments for the platform/vehicle interface is the use of horizontal extended door thresholds to reduce the gap between the vehicle and the platform. On new vehicles, the thresholds are designed and installed during the initial manufacture of the vehicles. On many of the legacy rail transit systems, the extended vehicle thresholds were retrofitted. Figure 7.1 shows two different types of door threshold extensions. Movable Vehicle-Based Gap Fillers Vehicle-based gap fillers are mechanical systems that extend from the door threshold to the edge of the platform. They are at the same height as the platform (see Figure 7.2). These devices are used to reduce the horizontal gap between the platform and the vehicle entrance. Most are permanently installed extensions at the doorsill. These devices also must interlock with the vehicle control system, and only operate when the door is in the closed position. Figure 7.3 shows an automatic mechanical gap filler that is used at each door of a commuter train in Rostock, Germany. Vehicle-Based Ramps and Bridging Plates Vehicle-based ramps and bridging plates also deploy from the vehicle threshold area, but they land on top of the platform. A ramp is typically longer than a bridging plate. All these vehicle- based devices may be automatically deployed at all doors or only deployed at individual doors Vehicle-Based Treatments to Improve Safety at the Platform/ Vehicle Interface
60 Manual to Improve Rail Transit Safety at Platform/Vehicle and Platform/Guideway Interfaces Figure 7.1. Vehicle-based threshold extensions. Figure 7.2. Vehicle-based gap filler, NCTD. Figure 7.3. An automatic mechanical gap filler in Rostock, Germany.
Vehicle-Based Treatments to Improve Safety at the Platform/Vehicle Interface 61 when activated by entering/exiting passengers. These devices are interlocked with the vehicle control system and only deploy when the door is in the closed position. In Figure 7.4, the photo on the left shows a short bridging plate deployed with the door clos- ing before the ramp is retracted. The image on the right shows a longer ramp deployed. Both mechanisms provide level boarding between the platform and vehicle for passengers who use wheeled mobility devices. Commuter rail vehicles may have portable ramps that are stored on the vehicle. These devices require train or platform staff assistance. These are shown in Figure 7.5. Figure 7.6 shows a manual ramp that attaches at the door threshold of a train. Vehicle-Based Between-Car Barriers The ADA regulations require that there be between-car barriers when more than one car is used and level boarding is provided. The use of vehicle- or platform-based between-car barrier systems is dependent on transit agency operations and uniformity or standardization of vehicle Figure 7.4. Bridging plate (left) and ramp deployed (right). Figure 7.5. Manual ramp stored on board (left); manually deployed wheelchair ramp (right) Metro-North. [Images of Metro-North © Metropolitan Transportation Authority. Used with permission].
62 Manual to Improve Rail Transit Safety at Platform/Vehicle and Platform/Guideway Interfaces lengths. Between-car barriers were introduced to reduce the risk of passengers tripping or fall- ing into the gap between vehicles on trains with two or more cars. The gap is due to the space between vehicles that is a result of the coupling devices and the frontal profile of the vehicle. Vehicle-based between-car barriers may not be appropriate due to frontal profile, exterior material, or structural design. Other factors that preclude the use of vehicle-based between-car barriers include track geometry or rail operations. Transit agencies that change the number of vehicles in a train consist during the day for peak hour and non-peak hour service indicated that vehicle-based barrier systems can also increase hazards for the train crews who couple and de-couple trains (19). The between-car pantograph gates shown in Figure 7.7 were initially designed in 1914 for operators in New York City; the fundamental concept of the paddle design has not changed in over a 100 hundred years. Another type of vehicle-based barrier used in Toronto is shown in Figure 7.8. San Diego Trolley operators reported incidents of people riding or jumping through the couplers. San Diego developed placards that are placed on the coupler (see Figure 7.9). These placards were designed and installed to discourage people from jumping through or riding the coupler between the vehicles. Door Closure Detection Technologies Vehicle doors with sensitive edges are a safety feature on passenger rail transit vehicles. A com- mon goal of all the sensitive door edge systems is to prevent a train from moving if there is a small object caught in the door. The edge of the door has sensors that detect small objects caught in a door when it is closing. The most sensitive sensors can detect an object as light as a dog leash. The activated sensors send signals through mechanical or electrical interlock systems that prevent the train from moving. Some detection systems have door push back mechanisms that will permit a passenger to push the door apart to release a caught object; doing so will prevent the train from moving. There is a range in the level of force required to push the doors apart. Figure 7.6. Manual vehicle-based wheelchair ramp.
Vehicle-Based Treatments to Improve Safety at the Platform/Vehicle Interface 63 Figure 7.7. Vehicle-based between-car barriers. [Images of NYC Subway © Metropolitan Transportation Authority. Used with permission]. Figure 7.8. Between-car barrier used in Toronto, Canada. Figure 7.9. Between-car barrier warning placards in San Diego, California.
