Maryland Transit Authority Metro Rail First Responders Training Manual by Terri Wright

Module 3

Third Rail

Case Study London, 2005 On the morning of July 7, 2005, Islamic terrorists detonated three bombs in quick succession aboard the London Underground trains across the city. Later, a fourth bomb was detonated on a double-decker bus. Fiftytwo people, plus the four bombers, were killed in the attack, and more than 700 were injured. After the first three bombs went off, a system alert was declared. The London Underground began to shut down operations, ordering trains to continue only to the next station and suspending all services. Nearly an hour after the initial bombings, a fourth bomb was detonated on the top deck of a double-decker bus after it had arrived at a bus station where people who had been evacuated from the Underground were boarding buses. Several people were injured, and surrounding buildings were damaged by debris. Initially, there was confusion as to the origin, method, and timings of the explosions. Authorities believed that the explosions had been caused by a power surge on the Underground power grid; a rapid series of power failures caused by the explosions looked similar to a cascading series of breaker operations that might result from a major power surge. A committee of inquiry afterwards recommended reviewing major incident training for all frontline staff, especially those working on the Underground. It recommended that a common initial rendezvous point be permanently staffed and recommended that stretchers and first aid equipment be available at Underground stations. And in response to the evidence that some firefighters refused to walk on the tracks to reach a bombed train because they had not received confirmation that the electric current had been switched off, the inquiry recommended a review into how emergency workers confirm whether the current is off after a major incident

n Damaged Underground train after a bombing at Aldgate tube station, London, England in July, 2005.

INTRODUCTION third rail A rail, located along side the running rail, that supplies the power to propel the railcars.

See Video 3-1 Overview of the Third Rail

The MTA trains and stations are powered by electricity. Electricity is supplied to the Metro stations by traction power substations. Metro trains run on rails called “running tracks,” but there is another rail—called the third rail (or contact rail)—that provides the electrical power to the trains. This third rail requires expertise, caution, and special attention. We will discuss the third rail in this module.

L e a rnin g O b j e ctiv e s The goal of this chapter is to help you work safely in the vicinity of energized and de-energized third rails. After reading this module and viewing the associated videos, you will be able to:

• Describe the principles of the basic electric circuit in the MTA system • Explain the role of the third rail • Identify the sections of a third rail • Safely step over the third rail from a clear area and from rail side • Explain how feeder breakers are tripped in main line and yard track areas by OCC, Yard Tower, or Traction Power personnel • Verify that power has been removed or restored to the third rail • Identify and operate an emergency trip station in the main line or the yard • List the information to report to MOCC after activation of the emergency trip button • List the steps to take if a person comes into contact with the third rail • React safely if stray current is detected • List the precautions to take near UPS battery rooms.

traction power substations (TPSS) Substations that convert conventional electric power from AD to DC to energize the third rail and power to propel the railcars.

Traction power The power used to propel the railcars.

Third rail power The power used to propel the railcars.

6 Module 3 • Third Rail

Traction Power Substations Traction power substations (TPSS) can be found at all Metro stations. These substations convert conventional electrical power from AC (alternating current) to the DC (direct current) that energizes the third rail to power the traction motors that propel the railcars. Traction power is also known as third rail power. (Figure 3-1). TPSS can be located in a variety of places: above or below ground, inside or outside of the right of way, or inside a station or attached to a station (Figure 3-2). In addition to those substations located at each Metro station, traction power substations are located at the Metro Yard and at the McDonough Road

Figure 3-1 Line art that shows the power coming from the municipal power grid, to the TPSS, and on to the third rail. Each leg of power should be labeled. The municipal side will be labeled “xx volts AC” while the traction power side will be labeled “750-volts DC”

n Traction power substation

service building. The Baltimore Gas & Electric Company (BGE) provides two separate power feeds to each substation. The power feeds are converted to direct current (DC) for traction power and to lower alternating current voltages (AC) for station power. We will discuss the AC or station power components of the TPSS in Module 4

Basics of Electricity Electrical current is the movement or flow of electrically charged particles from the source (positive side) to the ground (negative side.) A pathway, or circuit, is required for the energy to flow from one point to another. As long as the circuit is complete between the supply and return, it is considered to be a closed circuit. Any break in the line is considered to be an open circuit, and the electrical flow stops at that point. When the circuit is open, the energy available in the energized side of the circuit is called potential. Potential is measured as the difference

in energy between the energized side of an open circuit and the ground. We have all seen a bird perched on a high voltage power line with no ill effect. The reason the bird can sit there is that he is part of the circuit, and the wire is a much better conductor than the bird, so the energy continues its flow through the wire. But if the bird were to land with one claw on the wire and the other claw on a ground wire, it would provide a quick path for the energy to reach ground, and would be instantly electrocuted. (continued)

! Safety Alert Traction power substations contain high voltage up to 13,200 volts. For this reason, access to these substations is restricted to Metro traction power personnel.

ground The side of an electrical circuit that returns the power back to the source, or earth.

potential The difference in energy between the energized side of an open circuit and the ground side.

traction power substations 7

current collector shoe The metal object located near the wheels of the train that directly contacts the third rail to transfer electrical energy from the rail to the railcar.

! Safety Alert Contacting the third rail with any part of your body, even a fingertip, can result in instant death.

Coverboard The fiberglass cover that runs the entire length of the third rail. This coverboard helps prevent anything from falling directly onto the third rail.

8 Module 3 • Third Rail

When we want the electrical energy to do work, whether lighting a bulb, making heat, or turning a motor, the appliance we want to energize is introduced into the circuit between the energized side and the ground side, allowing electricity to flow through the appliance while maintaining a closed circuit and taking advantage of the moving electricity. In the Metro system, electricity is converted to other forms of energy such as heat, light, and mechanical power. Electricity is supplied by the substation and applied to the third rail, which is then transferred to the train motor by means of a current collector shoe. The current collector shoe works as the bridge between the third rail and the traction motors that propel the train, thus maintaining a closed circuit. The electricity flows through the motor, which is converted into mechanical energy that propels the wheels of the train and moves the train down the track. The electrical current then returns to the substation via the train wheels and running rails. This continuous path comprises an electrical circuit (Figure 3-3). If something conductive (such as the human body) comes into contact with the electrical circuit described above, it actually becomes part of the circuit and electrical current will

flow through it. Electrical current is measured in amperes. Less than one ampere (100ma) of electrical current can kill a person. Because the third rail power has to deliver enough energy to move several trains heavily loaded with people, the available current, or potential, between the third rail and the running rail measures in the thousands of amperes. The potential between the third rail and the running rail, or even bare ground, is more than capable of delivering instant death to anyone who completes the circuit.

Figure 3-1 A train motor electrical circuit, including the third rail and running rail. Include simple diagram of train motor circuit w/ third rail and running rail as part of the circuit

Third Rail Power Traction power, also known as third rail power, is used to propel the railcars. Electrical power is sent from the Baltimore Gas and Electric Company (BGE) at 13,200 volts AC, and is converted to 750 volts DC at the traction power substation. This electrical current then travels via underground cables that come up out of the ground periodically and attach to a specific piece of a third rail. The third rail is a massive conductor, and should always be considered energized. The third rail is located alongside of the running rail. It is a segmented rail that comes in many different lengths based on the system needs. The third rail has a fiberglass coverboard and sits on insulated pedestals about 4 inches higher than the running rails (Figure 3-4). The electrical current from the third rail is transferred to the train by a current collector shoe (Figure 3-5) that touches the third rail. Current collector shoes will be covered in more detail in Module 6, Railcars.

News Reports of Third Rail Electrocutions These news reports describe the deadly consequences that can result from coming into contact with the third rail. April 26, 2010 — Transit Worker Dies After Being Electrocuted by Third Rail on Queens Elevated Track Monday A veteran transit worker was electrocuted Monday when he slipped and fell on the third rail on a rain-soaked stretch of elevated tracks in Queens.

Because there are current collector shoes on either side of the train at the wheels, energy is transferred from one side to the other. This means that if the collector shoe is touching the third rail on one side of the train, the shoes on the other side are also energized. Contact with these shoes can result in electrocution.

August 10, 2010 — (Sun-Times Media Wire Chicago) Man Electrocuted After Falling onto Blue Line Tracks A 31-year-old man was electrocuted Monday after he lost balance while standing on a CTA Blue Line platform on the West Side and fell onto the third rail.

Figure 3-4 The third rail is located outside of the running rail. It is a segmented rail that comes in many different lengths based on the system needs. The third rail has a fiberglass coverboard and sits on insulated pedestals about four inches higher than the running rails

July 4, 2011 — Boy Electrocuted Fetching Football from Railway Tracks A teenage boy has died while trying to retrieve a football from a railway line in Merseyside (England). The boy went onto the tracks between Rock Ferry and Green Lane stations in Wirral at about 1815 BST on Sunday. British Transport Police (BTP) said that the boy, 16, was electrocuted by the third rail, which runs between the tracks. He was taken by ambulance to Arrowe Park Hospital where he was pronounced dead.

! Safety Alert

Figure 3-5 The electrical current from the third rail is transferred to the train by a current collector shoe.

The running rail used in the metro system is a continuous welded steel rail that acts as the “negative return” of the electric traction power system by completing the power circuit. As a rule, standing or walking on the running rails should be avoided. This is especially the case when a piece of running rail is broken (Figure 3-6). Not only could a broken rail shift without warning, the possibility exists that a voltage potential could be present on the broken running rail. The third rail should be de-energized before working in any area that contains a broken piece of running rail.

third rail power 9

See Video 3-2 for a demonstration of third rail energy.

Each section of third rail on the main line is fed from two separate feeder breakers—a “north” breaker and a “south” breaker. These breakers are located in two different, but adjacent substations (Figure 3-7). Note that both breakers must be tripped (or opened) to de-energize this third rail section. The only exception to this arrangement is at the end of line— at the Johns Hopkins station and the Owings Mills tail tracks, where a third rail section may only be fed by one DC feeder breaker, and therefore requiring that only one breaker be tripped to de-energize the third rail section.

Figure 3-7 In this illustration, the third rail section on main line Track 2 is fed from breaker 2N at substation “A” and from breaker 2S at substation “B.” Both breakers must be tripped (opened) to de-energize this third rail section.

Main line third rail sections are identified by section and track numbers. This information is engraved on an ID plate located on top of the third rail coverboard (see Figure 3-8a). In this example, the 2201 designates a section of rail on track 1 and the C represents the specific piece of rail within that 10 Module 3 • Third Rail

section. Metro yard third rail sections are identified by feeder and section numbers, engraved on an ID plate located on top of the third rail coverboard (Figure 3-8b). In this example, the YF6 means yard feeder breaker #6 and the D indicates that specific piece of rail.

Figure 3-8 Third rail sections are identified by ID plates attached to the third rail coverboard. (a) Main line third rail sections are identified by section and track number 2201C. (b) Metro Yard third rail sections are identified by feeder and section number YF6D.

Skill Sheet 3-1 Stepping Over the Third Rail When it is not convenient or practical to walk around a third rail section, stepping over the third rail is permissible (even when energized) if it is done properly and safely.

When approaching the third rail from a clear area:

See Video 3-3

for a demonstration of stepping over the third rail.

1 Look on the immediate and other side of the third rail for any obstructions, grade changes, or tripping hazards. 2 If obstructed, continue along the rail until you find an unobstructed area. 3 Lift one leg over the third rail and place it between the third rail and the closest running rail. When your footing is secure, shift your weight to that leg. 4 Lift your other leg over the third rail and step between the two running rails.

When approaching the third rail from the rail side: 1 Place one foot between the running rail and the third rail and look for any obstructions, grade changes, or other tripping hazards on the far side of the third rail. 2 If obstructed, continue until you find an unobstructed area, making sure you walk between the running rails and not between the running and third rail. 3 When your footing is secure and you are sure there are no tripping hazards on the far side of the third rail, shift your weight to that leg. 4 Lift one leg over the third rail and step into the clear area. 5 Lift your other leg over the third rail, step into the clear area, and continue walking.

third rail power 11

! Safety Alert Black and yellow caution tape placed on the third rail coverboard indicates that a potential tripping hazard or obstruction exists at that particular location (Figure 3-9). When stepping over the third rail, choose a location without caution tape or obstructions.

Figure 3-9 Third rail with an obstruction and marked with caution tape.

Removal of Third Rail Power

hot sticks Device used to determine whether a third rail is energized.

Removing power from a section of the third rail requires opening (or tripping) the corresponding feeder breaker(s) that feed that particular section. In main line track areas, this can be done remotely by the Metro Operation Control Center (MOCC) or locally within the substation by traction power personnel. In Metro Yard track areas, this can be done remotely by Yard Tower or locally within the substation by traction power personnel. Third rail power removal or restoration must be verified by direct measurement at the third rail by using an appropriate measuring device such as a set of hot sticks (see Skill Sheet 3-2). It should be noted that traction power for main line Tracks 1 and 2 are separate (see Figure 3-7). Track 1 may be de-energized while Track 2 is energized, or vice versa.

Skill Sheet 3-2 Verifying Third Rail Power Removal or Restoration To verify that third rail power has been removed or restored: 1 Obtain a hot stick and electrical safety gloves from the Station Control Center (SCC) booth or the traction power substation. . 2 After donning the safety gloves, verify that your hot stick is working properly by testing it on a known energized section of third rail. 3 Do not use the hot stick on third rail end approaches. Some approaches are insulated from the third rail and do not have power. 4 Apply the negative lead of the hot stick to the running rail first, and then apply the positive lead to the third rail. Be sure to make solid contact with the rails (If there is rust on the top of the third rail, scratch the top of the third rail to make good solid contact, as shown in Video 3-3). Remove the leads in the reverse order, first removing the positive lead from the third rail and then the negative lead from the running rail.

12 Module 3 • Third Rail

hot stick device

See Video 3-4 for a demonstration of verifying third rail power removal or restoration

Emergency trip stations (ETS)

Emergency Trip Stations Main Line Trip Stations Emergency Trip Stations (ETS) are located approximately every 800 feet along the main line right-of-way and at both ends of each station platform in the nonpublic area. An All ETS boxes are identified by a blue light on top of the box or cabinet (Figure 3-10a); the blue light is a locating marker, and has no bearing on the status of third rail power. ETS boxes are track specific for either Main line Track 1 or Track 2. ETS boxes or cabinets contain a Wayside Emergency Telephone (WET) for communicating with the MOCC, a red button for de-energizing the third rail, and a green indicator light that illuminates when the third rail is de-energized (Figure 3-10b). The red button is used to trip breakers in the substation to remove third rail power (Figure 3-10c). A diagram of the green and red buttons on the WET phone is shown in Figure 3-11.

Cabinets located every 800 feet along the main line right of way and at both ends of each station platform that contain a wayside emergency telephone, a red button for deenergizing the third rail, and a green indicator button that illuminates when the third rail is de-energized.

Wayside emergency telephone (WET) Telephones located in emergency trip stations that communicate directly with the OCC.

c Figure 3-10 a) An above ground ETS box identified by its blue light. b) An open ETS box with a red push button for de-energizing the third rail, a green light that illuminates when the third rail is de-energized, and a WET phone. c) An open ETS in an underground station with a red push button, a green indicator light, and WET phone.

Figure 3-11 A detail showing the emergency trip button to deenergize the third rail. When the third rail is de-energized, the green light will turn on.

emergency trip stations 13

! Safety Alert The emergency trip button should be pushed only when there is an imminent threat to someone’s life or safety.

When an emergency trip is generated, either by pushing an ETS button or by MOCC, the corresponding feeder breaker(s) are automatically tripped and “locked out.” The emergency trip “lock out” feature must be reset (by MOCC or Traction Power personnel) before the associated breakers can be closed to restore power. When an ETS button is activated, it must be followed up with a call to MOCC. Use the WET phone in the cabinet to inform MOCC of the following: • Your identity, including your name and department • Your location, including the station, chain marker, and building

address

• The reason you activated the ETS • What action the OCC needs to take.

Yard Trip Stations

» Emergency trip buttons

Figure 3-12 There are three emergency trip buttons in the Metro Yard.

There are three emergency trip buttons for quickly de-energizing third rail sections in the Metro Yard (Figure 3-12). These buttons are located on the side of the Wabash Rail Shop building, on the wall facing the Metro Yard. Two of the buttons are at each end of the building, and the third button is in the middle of the building (Figure 3-13). Pushing any one of these buttons will deenergize all third rail sections in the entire Metro Yard. If an emergency trip button has been activated in the Metro Yard, Yard Tower must be informed immediately about the situation.

Skill Sheet 3-3 Rescuing a Person in Contact with the Third Rail If a person comes into contact with an energized piece of third rail, follow these steps: 1 Remove third rail power at an emergency trip station. 2. C ontact MOCC (if on main line), Yard Tower (if in the metro yard), or SCC booth (if in the station), and tell them to call for EMS to respond. 3. B reak the victim’s contact from the third rail. Without touching the victim or the any of the rails, use a dry, nonconductive material or device, such as a piece of clothing or a plastic or wooden object and quickly pull the victim away from the rail.

! Safety Alert DO NOT BECOME PART OF THE ELECTRICAL CIRCUIT! Do not attempt this unless you can clearly secure the nonconductive device to any part of the patient’s body or extremities without touching the patient. 4 If available, use a Class-C fire extinguisher to extinguish any fires if the patient is burning. 5 Start CPR only after the patient is no longer contacting the third rail.

14 Module 3 • Third Rail

See Video 3-5 for a demonstration of rescuing a person in contact with the third rail.

! Safety Alert

Other Third Rail CONCERNS Stray Current The normal return path for third rail current is via the running rails (not earth ground), However, electrical current will take the path of least resistance. If a situation arises where the current “sees” the normal return path as a higher resistance than going into the ground, it will go into the ground. For example, current can be conducted by a metal object that comes into contact with the rails or railcars, or if someone makes contact with one of these items. Although the voltage level may not be lethal in a case like this, the shock can cause involuntary muscle movement that could cause a person to fall. If you encounter a situation where a metal object is resting against a running rail or railcar, treat it as if it is energized.

Emergency Power and Battery Rooms In the event of a power failure, the uninterruptible power supply (UPS) provides emergency reserve power to emergency lighting and other critical loads. (Figure 3-14a). The UPS gets its emergency reserve power from a large bank of lead acid batteries (Figure 3-14b) located in a separate room near or adjacent to the room in which the UPS machine is located. Lead acid batteries produce hydrogen gas fumes, but not at dangerous levels during normal operating conditions. However, if the batteries malfunction or the UPS battery room’s ventilation system does not operate properly, highly flammable or explosive hydrogen gas can accumulate at dangerous levels. UPS battery rooms are equipped with gas detectors that will sound an alarm if dangerous levels of hydrogen gas are reached (Figure 3-14c).

Do not use bare hands to remove the object. Instead, use a nonconductive object or wear gloves to pull it free from the potential electrical circuit before picking it up. Note: if a metal object is in contact with the third rail, DO NOT attempt to remove it without fist de-energizing that third rail section. This is something that should be reported to OCC so that the proper department can take the proper actions to remove the item.

uninterruptible power supply (UPS) Rooms containing a large bank of lead acid batteries that supply power for emergency lighting and other critical loads in the event of a power failure.

Figure 3-14 a) The uninterruptible power supply (UPS) battery room. b) Bank of lead acid batteries. c) Gas detectors will sound an alarm if batteries emit dangerously high levels of hydrogen gas fumes.

! Safety Alert • N ever do anything that could produce a spark or flame in a battery room. An explosion could occur. • B attery rooms are equipped with gas detectors. Never enter a battery room if the gas detector has sounded an alarm. • Make sure the Fire Department is notified if an alarm is activated.

other third rail concerns 15

Key Points ✔ The Metro trains and stations are powered by electricity.

Traction power substations contain up to 13,200 volts of electricity, which is converted to the 750 volts of DC power that is delivered to the trains via the third rail, through the collector shoes. The circuit is completed when the energy flows through the traction motors to the wheels, then to the running rails. The third rail is always energized with high DC power and is a constant hazard to anyone who comes into contact with the rail.

✔ The third rail runs alongside the running rails on insulated pedestals about

4 inches higher than the running rails and has a fiberglass coverboard over its entire length. The running rails are continuous welded steel and act as the negative return, or ground, for the electrical circuit. Except for the tail line sections, each section of the main line is fed from two separate feeder breakers. The breakers on either side of the third rail section must be opened before the section is de-energized.

✔ Opening the feeder breakers can be done remotely by the MOCC, or by

Yard Tower if the track is in the Metro Yard track area. Third rail power removal or restoration should be confirmed by using a measuring device such as a hot stick.

✔ It is important that the proper procedures are followed anytime you must

step over a third rail. The main points of these procedures involve making sure there are no trip hazards, that you have sure footing, and that you never have both feet between the running rail and the third rail. In most cases, black and yellow caution tape on the third rail coverboard indicates that a potential tripping hazard exists in that particular location.

✔ Emergency Trip Stations (ETS) contain a Wayside Emergency Telephone

(WET) for communicating directly with the OCC, a red button for deenergizing the third rail and a green indicator light that illuminates when the third rail is de-energized. When tripped, the corresponding feeder breakers are automatically locked out and must be reset by MOCC or Traction Power personnel before the associated breakers are closed to restore power. There are three emergency trip buttons in the Metro Yard area that will de-energize all third rail sections in the entire Metro Yard area. Notify Yard Tower immediately about the situation if you trip one of these buttons.

✔ Stray current can also be a problem if a metal object comes into contact with the rails or railcars. While seldom lethal, the small shock one could receive when touching the object could startle the person, causing him/ her to stumble and fall into the third rail, or to drop anything they may be carrying at the time.

✔ Emergency

power is available through uninterruptible power supplies (UPS) for powering emergency lighting and other critical loads. These UPS systems are located in rooms that are monitored for dangerous hydrogen gas build-up. Never do anything that could produce a spark in a UPS room, and never enter a UPS room when the alarm is sounding. Make sure the Fire Department is responding if an alarm is activated in a UPS room.

16 Module 3 • Third Rail

Assess Your Understanding

Answering the following questions will help you determine whether you understand the module. If you have trouble with the questions, review the content on the specified pages. 1 What are the principles of the basic electric circuit in the MTA system? [Pages xx – xx] ____________________________________________________________________________ ____________________________________________________________________________ ____________________________________________________________________________

2 What is the role of the third rail?

[Pages xx – xx] ____________________________________________________________________________ ____________________________________________________________________________ ____________________________________________________________________________

3 How are third rail sections identified?

4 How do you step over the third rail from a clear area and from rail side? [Pages xx – xx] ____________________________________________________________________________ ____________________________________________________________________________ ____________________________________________________________________________

5 How are feeder breakers tripped in main line and yard track areas by OCC, Yard Tower, and Traction Power personnel? [Pages xx – xx] ____________________________________________________________________________ ____________________________________________________________________________ ____________________________________________________________________________

6 How do you verify that power has been cut or restored to the third rail? [Pages xx – xx] ____________________________________________________________________________ ____________________________________________________________________________ ____________________________________________________________________________

7 How do you identify and operate an emergency trip station in the main line or the yard? [Pages xx – xx] ____________________________________________________________________________ ____________________________________________________________________________ ____________________________________________________________________________

8 What information should you report to OCC after activation of the emergency trip button? [Pages xx – xx] ____________________________________________________________________________ ____________________________________________________________________________ ____________________________________________________________________________ ____________________________________________________________________________ ____________________________________________________________________________

assess your understanding 17

9 What should you do if a person comes into contact with the third rail? [Pages xx – xx] ____________________________________________________________________________ ____________________________________________________________________________ ____________________________________________________________________________ ____________________________________________________________________________ ____________________________________________________________________________

10 What should you do if stray current is detected? [Pages xx – xx] ____________________________________________________________________________ ____________________________________________________________________________ ____________________________________________________________________________

11 What precautions should you take near UPS battery rooms? [Pages xx – xx] ____________________________________________________________________________ ____________________________________________________________________________ ____________________________________________________________________________

Glossary Terms

indicates a video is available.

Coverboard The fiberglass cover that runs the entire length of the third rail. This coverboard helps prevent anything from falling directly onto the third rail. Current collector shoe The metal object located near the wheels of the train that directly contacts the third rail to transfer electrical energy from the rail to the railcar. Emergency trip stations (ETS) Cabinets located every 800 feet along the main line right of way and at both ends of each station platform that contain a wayside emergency telephone, a red button for de-energizing the third rail, and a green indicator button that illuminates when the third rail is de-energized. Ground The side of an electrical circuit that returns the power back to the source, or earth. Hot sticks Device used to determine whether a third rail is energized. Potential The difference in energy between the energized side of an open circuit and the ground side. Third rail A rail, located along side the running rail, that supplies the power to propel the railcars Third rail power The power used to propel the railcars Traction power substations (TPSS) Substations found at Metro stations that . . . Traction power The power used to propel the railcars Uninterruptible power supply (UPS) room Rooms containing a large bank of lead acid batteries that supply power for emergency lighting and other critical loads in the event of a power failure. Wayside emergency telephone (WET) Telephones located in emergency trip stations that communicate directly with the OCC. 18 Module 3 • Third Rail

Chart 3-1 Access Gate Locations by Chain Marker Main Line 2 by Chain Marker

Main Line 1 by Chain Marker

694

678

688

658

668

641

653

621

631

611

581

579

571

579

571

568

Chart 3-2 Drive-Through Gates 1 C M 400 T1 Spring and Park Ave. 2 C M 426 T1 Cedar Rd and Rocklaho Rd 3 C M 429 T1 East end of Milford Mill Metro Parking Lot. 4 C M 455 T1 Upland Road 5 C M 492 T1 Kingston Road and McHenry Road 6 229 Portal Entrance.

reference charts 19