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22 Proper shoes or boots with rubber soles must be worn River LINE (no high heels, sandals, sneakers, or steel-toed shoes). Employees must not wear clothing or shoes that will Roadway workers are required to wear a high-visibility vest hinder them in any way during the performance of their or other approved garment, approved footwear, hard hat or duties. approved head covering, and safety glasses when on or about Raincoats longer than knee length are prohibited. the track (8, p. 3). Proper work gloves or leather gauntlets are needed when engaged in maintenance work, track cleaning, installation WARNING AND PROTECTIVE DEVICES of light banks, and the like. AND TECHNOLOGY When a worker wears special clothing, particularly hoods and ear protection, care must be taken so that the All of the systems involved in the study use some form of individual is fully aware of the working environment, warning lights, audible devices, or portable trip or stop paying special care to all types of traffic in all types of equipment to enhance the level of protection afforded to a weather conditions. work site. Exception--Orange outer garments with high-visibility reflective strips, which have been approved by the Safety Department, may be worn on the ROW in place of an Flags and Warning Lights approved vest. Traditionally, "flagging" was done with colored flags, hence Supervisors are required to: the name. Similar to the universal application of colors to railroad and road signaling, red means stop, yellow is caution Maintain an adequate supply of PPE for worker safety; or proceed at a reduced speed according to agency rules, and Issue the approved PPE to employees as necessary, as green is an indication to resume normal operating speeds for part of their uniform; the line or area. Over time these flags, which are still used by all Provide PPE (i.e., flagging equipment, hard hats) for systems in outdoor, daylight conditions, have been supplanted special details; in tunnel and after-sunset situations by colored portable Provide appropriate training in use and care of PPE warning lights that can be powered using hard-wire power or (i.e., respiratory and hearing protection) and provide batteries. appropriate fit testing for respiratory protection; Maintain a Material Safety Data Sheet (MSDS) List for These flags or lights can be held by a flagger or watchperson; protection against hazardous chemicals and materials; hung along the track; placed in the gauge or along the track and on the ground; or placed in or on top of cones in the gauge or Administer and ensure compliance with all procedures along the track; according to each system's rules and rules for associated with the rule book (6, pp. 4344). specific types of flagging. These flags and lights communicate to train operators specific orders, based on the rules, to reduce speed, stop, proceed at reduced speed, or proceed at normal Maryland Transit Administration speed (see Figure 8 for typical flagging signal colors and meanings or applications, and Figure 9 for examples of flags Employees working on or about MTA light rail tracks must and lights). follow these rules: Wear approved safety vests properly fastened over outer Toronto Transit Commission clothing to ensure high visibility; Wear approved hardhat (ANSI Z89); A successful practice highlighted in interviews with safety, Wear approved safety glasses (ANSI Z87). Head cover- operations, and maintenance personnel was the TTC's Track ing must not interfere with seeing, and sunglasses, hats, Level Safety Team's initiative to implement the use of or any other attire must not restrict vision or distort color blue light warning devices as a signal to train operators perception. Sunglasses are prohibited at night. that workers are at track level, between stations. Based on Wear approved hard sole shoe that provides adequate pro- positive feedback, the program has evolved significantly tection (ANSI Z41). Sandals, cloth, canvas, wedge type, over time. high heel, athletic, or recreational shoes are prohibited. Jewelry, if worn, must not constitute a safety hazard or Initially, all crews were required to place a blue flashing light impair an employee's ability to perform his or her duties in the track bed 50 ft from the end of a station. The purpose in a safe and efficient manner; of the light was to alert train operators to the presence of While operating or working around noisy equipment, workers at track level between the station they were depart- employees can only use earplugs or hearing protection ing from and the next station. This safety practice was further if there is adequate track protection against approaching enhanced with the posting of blue speed-limit signs along the trains (7, pp. 1.81.10). track bed in advance of low visibility sections of track, such

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23 Object Color Meaning/Application Light or Flag Red Stop Light or Flag Yellow Reduce speed (typically ten (10) miles per hour or less) and be prepared to stop within half the sight distance Light or Flag Orange Reduce speed (typically ten (10) miles per hour or less) and be prepared to stop within half the sight distance White Light With appropriate arm motions can be used to signal trains to stop, reduce speed, proceed, or back up White Disc Used to communicate directions from watchmen to work crews, including "Clear the track" and "Resume work" Light or Flag Green Resume normal operating speed for the area and/or conditions FIGURE 8 Examples of flagging signal colors (Courtesy: MBTA). FIGURE 9 Examples of flags and lights. (Clockwise from above left ) Red (stop) flag placed in cone in gauge of track; flagger using red flag to stop an oncoming train; green flag in cone and green light on station platform indicating that trains are clear of a work site and can resume normal operating speed; battery-powered warning light, most commonly used underground or after sunset (Courtesy: MBTA).

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24 as blind curves. The signs remind operators to reduce train Workers Ahead," will hear an audible "beep" tone in the speed to 15 mph when they have observed a blue light, in operating cab, and will see a blue "WAW" LED flashing on case workers are present. TTC is now testing an automated the radio unit. The operator can press a "Cancel" button to Work Area Warning (WAW) system, developed in-house by silence the tone, but the text message and the flashing blue LED the Signals Engineering and Communications Department, cannot be cleared or stopped by the operator. The operator on the Sheppard Subway line. will proceed according to all work zone rules and regulations, being prepared to stop in the event that the crew or equipment The WAW system establishes standard locations at each is unable to clear track level safely. Once the train enters the station and integrates the placement of the warning light with next station; all alarms and notifications will be canceled a radio-frequency identification (RFI) tag. WAW builds on (see Figure 10). the tag system technology used to execute customer station announcements, to supply automated track worker visual and The TTC reported that it can implement the WAW system audible warnings to train operators. Each station is equipped at relatively low cost because it uses existing communications with a blue light tag placed in a yellow holder mounted in a infrastructure. Ultimately, TTC plans to evolve the WAW standard location on the station wall. The work crew obtains system in the following ways: approval to enter track level, retrieves the blue light and RFI tag from the holder, and places it in the designated location Permanently integrate the blue lights and controllable on the track bed. As a train leaves the station, the operator RFI tag into the existing system circuitry to eliminate should observe the flashing blue light at track level and sound the need for workers to place the light and tag in the a long blast on the horn. In addition, the operator will receive gauge to establish protection. Initially, this hard-wired a text message on the cab radio display indicating "Caution configuration would be activated through an access-

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25 controlled panel at the ends of each station platform. an area where a piece of rail or switch has been removed Ultimately it would be activated and deactivated through (see Figure 12 for examples of barricades). the control center following notification from a track- level worker entering or exiting the ROW with his or her crew. Portable Train Stop A second phase would integrate the WAW into its Several systems use a relatively low-tech but proven device speed control tag system to enforce speed limits in called a portable train stop (PTS) or portable trip device. work zones. This would be done by first warning an Older systems such as NYCT, MBTA, and TTC have used operator that he or she is exceeding the speed limit, these devices for several decades. On some or all the lines on followed by the activation of a train-stop procedure in these systems, fixed train stops or trip devices are still an which the train would come to an emergency stop. This integral part of the signal system. Whether fixed or portable, would not be done by controlling or reducing a train's the principle of the device is that it is placed next to a rail and speed, as is possible in some Automatic Train Operation has an "arm" that will trip a corresponding arm on the bottom systems. of the rolling stock, which will then stop the train by activating the brakes. On the TTC system, all revenue and nonrevenue Current TTC plans project the completion of full testing on work equipment is equipped with trip arms activated by pass- the initial RFI tag-based WAW system and implementation ing a portable or fixed trip device (see Figure 13 for an exam- of system-wide installation on all subway lines in 2012. ple of a portable trip device). Audible Warning Devices The procedure for using the portable train stop in flagging and work-site protection is consistent across the agencies that Flaggers and watchpersons are always required to carry an use these devices. For example, at NYCT the PTS, designed audible warning device, most often a whistle or compressed primarily for use by flaggers, is applied to the rail to ensure air-powered horn. These are used to warn or communi- the positive stop of an approaching train if a train operator cate with other flaggers, watchpersons, or employees at the fails to acknowledge the stop signal displayed by the flagger. work site. See Figure 11 for examples of audible warning The PTS is used in connection with flagging operations only devices. after the proper display of caution lights or flags in accordance with the rules. Barricades The PTS may be used at any point on a track where a Another layer of protection, which is used most commonly in temporary train-stopping device is required. The PTS consists longer-duration work sites, is physical barriers or barricades to of two separate units, one known as the base, the other as the indicate that a track is out of service. These devices are usually stop arm. The effect of the PTS, when properly installed, is intended not only to protect the track workers but also to the same as that of the automatic stop arm located at signals. prevent a revenue train or other on-track movements from When in position, the stop arm engages the tripping device of colliding with equipment at the work site or running through the moving train, causing an emergency application of the FIGURE 11 Examples of audible warning devices. Compressed-air, hand-held horn used by flaggers (left ) and whistle that is part of required PPE for most track workers and all flaggers in the study (right ) (Courtesy: MBTA).

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26 FIGURE 12 Examples of barricades. Commercially available barricade in place (top left ); clamp-on stop flag and battery-powered red light (top right ). Bottom photo shows work area on two-track ROW protected by barrier on each track using boards chained to rails and battery-powered red lights mounted in center of gauge (Courtesy: MBTA). brakes. The PTS must be applied to the track at the same avoid unnecessary tripping of a train. Only the flagger plac- location where the flagger is stationed, and must be placed so ing a particular PTS, or the flagger's supervisor, may remove that it will engage the tripping device on the forward end of the stop arm once it has been placed in the tripping position, an approaching train. except upon orders of the Control Center desk superintendent (9, Rule 3.79). After the necessary caution lights or flags have been set up in accordance with the rules, the base of the PTS must be clamped securely to the base of the rail, with the stop arm dis- Electronic Train and Track Worker Detection Devices engaged. When ready to flag trains using the PTS, the flagger must place the stop arm securely in its proper tripping position MBTA and MTA are using devices manufactured by ProTran in the base. The flagger must display the red flag or the red that communicate to track workers and train operators the light to the full view of the operator of an approaching train. presence of an approaching train or of employees along the When conditions are safe to allow the passage of a train, the ROW. The ProTran devices were initially developed and tested flagger must remove the stop arm and perform flagging through the TRB Transit IDEA Program. Completed in 2008, operations in accordance with the rules. Transit IDEA J-04/IDEA 55 "Warning Device for Rail Transit Personnel for Approaching Trains" assisted in bringing this Under no circumstances should the stop arm be in its device from concept through prototype development and tripping position after the flagger has given a "proceed" signal evaluation phases. Site testing of the device, conducted in the to the train operator. Flaggers must exercise special care to IDEA Program, was done in Cleveland (GCRTA), Philadelphia

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27 The devices use wireless technology for advanced detection. They are not a "fail safe" feature (10). MBTA track workers who were interviewed for this study expressed concern regarding the reliability of the equipment and complained about its overall size and weight when transporting it. They did, however, welcome the extra level of warning and protection that it affords. Maryland Transit Administration Using the same equipment, MTA has taken implementation to the next step by installing transmitter/receivers in the cab of each light rail vehicle. Each employee accessing the ROW is also issued a PAD or a DFD that he or she is required to wear and use while on the ROW. The PADs and DFDs are tested at the beginning of each shift to ensure battery life and functionality. This system not only alerts ROW employees to the presence of approaching trains, but also alerts operators to the presence of employees on the ROW. Like MBTA, MTA has not altered any existing rules and procedures, but has added this technology as another layer of protection for track workers. Aside from the rule that employees must wear and use the devices when on the ROW, FIGURE 13 Example of portable trip device (Courtesy: TTC). MTA also now requires employees who experience mechan- ical failure of their device to leave the ROW and wait for a replacement PAD or DFD before returning to work. (SEPTA), and Boston (MBTA). TTC is also field testing a separate product called TrackSafe, being developed by Some MTA managers stated that there have been some Bombardier. issues with battery life in the PADs and DFDs, and that employees have complained about the bulk and discomfort associated with wearing the devices. Like MBTA however, Massachusetts Bay Transportation Authority supervisors and managers welcome the concept of an additional layer of protection (see Figure 14). According to MBTA personnel, as of March 2011, the ProTran devices are only used on the Green Line (light rail line), as a supplement to established rules for flagging and track Toronto Transit Commission protection. The device is placed along and connected to the track and transmits a signal to personal alert devices (PADs) TTC hosted a pilot of the TrackSafe product in fall 2011. worn by track workers and to a designated flagger device The goal of TrackSafe is to provide improved location aware- (DFD), a receiver worn by flaggers. ness and relevant alerts to train operators and roadway work- ers. Roadway workers are equipped with a wrist band that MBTA states in the instructional training for this equip- they use to "tag in" at a kiosk at their point of entry to track ment that: level. No other equipment is required for the roadway worker, allowing the worker to carry necessary equipment and to These products do not replace existing MBTA policies enhance safety with minimal effort. Upon check-in, the work- and procedures. They will work in conjunction with ers enter their work plan, or simply confirm a previous reser- safety procedures, adding an additional layer of safety vation they have made with the Control Center. The check-in to track workers. software also provides for "rules" enforcement, ensuring that They provide visual and audible warnings to the flaggers only authorized people can access track level. and work crew. They provide a designated employee with the option to As the roadway work crew proceeds at track level, the warn flaggers or the work crew. crew tags in at various checkpoints, creating an Alert Warning