800 RAIL GRADE CROSSINGS Traffic Engineering Manual TABLE OF CONTENTS … · 2014-01-17 · 800...

800 RAIL GRADE CROSSINGS Traffic Engineering Manual

(January 20, 2012) October 23, 2002 8-1

TABLE OF CONTENTS

Part 8 - RAIL GRADE CROSSINGS

800 GENERAL ...............................................................................................8-3

801 SIGNING..................................................................................................8-3 801-1 General ................................................................................................................8-3 801-2 STOP Signs at Highway-Rail Grade Crossings ................................................. 8-3

801-2.1 General............................................................................................ .... 8-3 801-2.2 Grade Crossings Identified for Lights and Gates .............................8-3 801-2.3 Grade Crossings Not Approved for Lights and Gates ........................8-4

802 MARKINGS ............................................................................................ 8-5 802-1 General .................................................................................................................... 8-5 802-2 Railroad Pavement Marking Symbol ................................................................... 8-5

803 ILLUMINATION ...................................................................................... 8-7

804 FLASHING LIGHT SIGNALS, GATES & TRAFFIC CONTROL SIGNALS 804-1 General ........................................................................................... 8-9

804-2 Definitions .............................................................................................................. 8-9 804-3 Railroad Preemption of Traffic Signals .............................................................8-11 804-3.1 General .....................................................................................................8-11 804-3.2 When to Preempt .....................................................................................8-11 804-4 Highway-Rail Grade Crossing Warning System Interconnection Design

Guidelines ............................................................................................................8-12 804-4.1 Purpose .....................................................................................................8-12 804-4.2 Operation ..................................................................................................8-12 804-4.3 Traffic Signal Interface .............................................................................8-12 804-4.3.1 Traffic Signal Controller .........................................................8-12 804-4.3.2 Nomenclature and Terminals ...............................................8-14 804-3.3.3 Harness ..................................................................................8-14 804-4.3.4 Preemption Input Test Switch Panel .....................................8-14 804-4.3.5 Indicator Panel .......................................................................8-15 804-4.4 Traffic Signal Controller Unit ....................................................................8-16 804-4.5 Railroad Interface .....................................................................................8-17 804-4.6 Interconnect Cable ...................................................................................8-18 804-4.7 Testing.......................................................................................................8-19 804-4.8 Working Drawings ....................................................................................8-19 805 RUMBLE STRIPS ................................................................................. 8-21

830 PLANNING / PROGRAMMING ............................................................ 8-23 830-1 General ..................................................................................................................8-23 830-2 Grade Separation Program .................................................................................8-23 830-3 New or Upgrade Highway Traffic Signal Projects ...........................................8-23 830-4 New or Upgrade Railroad Warning System Projects ......................................8-24

840 DESIGN INFORMATION ...................................................................... 8-25 840-1 General ..................................................................................................................8-25 840-2 Design of Locations with Railroad Preemption ...............................................8-25 840-2.1 General....................................................................................................8-25 840-2.2 Railroad Warning Devices ......................................................................8-25


8-2 October 23, 2002 (January 20, 2012)

840-2.3 Highway Traffic Signal ............................................................................ 8-26 840-2.4 Intersection Geometrics and Configuration ........................................... 8-28 840-3 Design of Pre-Signals.......................................................................................... 8-29 840-4 Design of Queue Cutter Signals ........................................................................ 8-30

850 CONSTRUCTION................................................................................. 8-31

860 MAINTENANCE / OPERATIONS ......................................................... 8-31

880 RESEARCH.......................................................................................... 8-33 880-1 General .................................................................................................................. 8-33 880-2 Buckeye Crossbuck ............................................................................................ 8-33

895 REFERENCE RESOURCES ................................................................ 8-35 895-1 General .................................................................................................................. 8-35 895-2 Related ORC References .................................................................................... 8-35 895-3 Railroad Grade Separation Program Policies and Procedures Manual ....... 8-35 895-4 Railroad-Highway Grade Crossing Handbook ..............................................8-35

895-5 AREMA Communication & Signal Manual of Recommended Practice ................................................................................................................. 8-35

896 FORMS INDEX ..................................................................................... 8-37 896-1 Highway-Rail Grade Crossing Warning System Railroad Configuration and Timing Requirements ......................................................... 8-39

898 FIGURES INDEX .................................................................................. 8-41 898-1 Example of an Interconnection Warning Label ............................................... 8-43


Revised January 20, 2012 October 23, 2002 8-3

Part 8 – RAIL GRADE CROSSINGS

800 GENERAL

OMUTCD Part 8 addresses traffic controls at highway-rail grade crossings and highway-light rail grade crossings. Very few, if any routes under ODOT’s jurisdiction involve traffic control at highway-light rail transit grade crossings. Part 8 of the Traffic Engineering Manual (TEM) provides additional guidance for use of traffic control devices at these crossings. See TEM Part 4 (Signals) for additional information about traffic controls at rail grade crossings, including Signal Preemption and Warning System Interconnection design guidelines. The FHWA Railroad-Highway Grade Crossing Handbook (Section 895-4) also provides useful guidance when evaluating and prioritizing improvements to highway-rail grade crossings.

801 SIGNING

801-1 General Signs used at highway-rail grade crossings are addressed in OMUTCD Chapter 8B. 801-2 STOP Signs at Highway-Rail Grade Crossings

801-2.1 General

ORC Section 4511.43 defines the obedience required to a STOP sign and ORC Section 4511.61 allows erection of STOP signs at railroad crossings where approved by ODOT.

Prior studies have indicated that: STOP signs at highway-rail grade crossings are generally not effective; driver compliance to these devices is poor; the use of these devices creates contempt and disrespect for all STOP signs; and that STOP signs at highway-rail grade crossings are often responsible for an increase in rear-end collisions at these crossings. Therefore, it is ODOT’s policy to disapprove the installation of STOP signs at highway-rail grade crossings, except for very unusual or exceptionally hazardous locations.

The purpose of this section is to identify the principles and guidelines which shall be used in determining if a highway-rail grade crossing approach shall have STOP sign control.

801-2.2 Grade Crossings Identified for Lights and Gates

When a highway-rail grade crossing has been identified by the Ohio Rail Development Commission (ORDC) or the Public Utilities Commission of Ohio (PUCO) as warranting flashers and gates, temporary STOP signs shall be installed at the crossing unless it is determined that the STOP signs presents more of a hazard to the traveling public than the crossing.

The location shall be evaluated considering the following:

1. The condition of any traffic control devices in immediate proximity of the crossing.

2. Cross-corner sight distances for both approaches to the crossing.

3. Geometrics and approximate relative elevations, if relevant.

4. Location of all traffic control devices (standard and non-standard).


8-4 October 23, 2002 Revised January 20, 2012

5. Location and type of visual obstructions.

6. Average daily traffic (provided on diagnostic survey form).

7. Other corrective action, such as rumble strips, site view improvements or illumination, that illumination that could be used instead of STOP signs.

On ODOT-maintained highways, ODOT shall evaluate whether placing STOP signs at a particular crossing presents some overriding highway safety issue. If not, the STOP signs shall be installed.

For requests involving highway-rail grade crossings on other highways, the process is under review. The jurisdiction should contact OTE, ORDC or the PUCO.

If the location is currently signed with a Buckeye Crossbuck, ODOT or the local public agency, as appropriate, shall instruct the railroad company to remove the YIELD shields prior to installation of the STOP signs. Also, where feasible, when a STOP sign is installed, a Stop Ahead sign (W3-1 or W3-1a) shall be placed in conjunction with the Railroad Advanced Warning Sign (W10-1).

When the flasher and gates are installed, the STOP and Stop Ahead signs shall be removed.

801-2.3 Grade Crossings Not Approved for Lights and Gates

As noted in Section 801-2, ORC Section 4511.61 allows the installation of STOP signs at highway-rail grade crossings only with the approval of the Director of Transportation.

It was agreed that for the life of the Buckeye Crossbuck experiment (Section 880-2) no changes would be made in the traffic control at highway-rail grade crossings in the State, except for the process described in Section 801-2.2 for temporary STOP signs at crossings approved for installation of lights and gates.

Although this experiment has been concluded, other action is being considered on a national level that would involve the signing at highway-rail grade crossings, and work on preparation of new guidelines for installation of STOP signs at these crossings has been suspended pending discussion with FHWA regarding these changes.



802 MARKINGS

802-1 General The general standards for markings at rail grade crossings are addressed in OMUTCD Chapter 8B and Figures 86 through 8B-9. 802-2 Railroad Pavement Marking Symbol As noted in OMUTCD Figure 8B-6, the highway-rail grade crossing pavement marking symbol consists of the “RXR and two 24-inch wide transverse lines.” However, for contract plan payment purposes, the “railroad symbol marking” is described in CMS Item 641.08 as including the crossbuck, two “R”s, two transverse lines and a stop line. The symbol is also illustrated in SCD TC-71.10. The highway-rail grade crossing alternative (narrow) pavement markings shown in OMUTCD Figure 8B-7 should not be used on ODOT-maintained routes unless a narrow roadway makes the standard symbol impractical.



Intentionally blank.



803 ILLUMINATION

When an engineering study determines that better nighttime visibility of the train and the highway-rail grade crossing is needed, illumination at and adjacent to the highway-rail crossing may be installed. Standards and guidelines for highway lighting highway-rail grade crossings are in Part 11 of this Manual. Illumination at these grade crossings is also addressed in the American National Standard Practice for Roadway Lighting (RP-8-00), available from the Illuminating Engineering Society of North America (IESNA) (see Table 197-3).



804 FLASHING LIGHT SIGNALS, GATES & TRAFFIC CONTROL SIGNALS

804-1 General Signals and gates used at highway-rail grade crossings are addressed in OMUTCD Chapter 8C. The interconnection and preemption of Highway Traffic Signals with Highway-Rail Grade Crossing Warning Systems are addressed in OMUTCD Chapter 8C.10, but substantial additions and clarifications are contained in the TEM Parts 1, 4, and 8 for use within the State of Ohio. In Part 8 also see Chapters 830 and 840 for additional information about preemption and interconnection with highway-rail grade crossing warning systems. 804-2 Definitions “To promote understanding of common terminology between highway and railroad signaling issues,” OMUTCD Section 1A.13 provides definitions of a number of related terms, such as preemption, interconnection, simultaneous preemption, advance preemption, advance preemption time, minimum track clearance distance, clear storage distance, right-of-way transfer time, queue clearance time, separation time, maximum preemption time, minimum warning time, and pre-signal. Section 1501-3 also provides other definitions. This Section includes several more definitions, and for clarification, provides additional information about several of the OMUTCD definitions: Minimum Track Clearance Distance (MTCD) – is defined in OMUTCD Section 1A.13 as: “for standard two-quadrant railroad warning devices, the minimum track clearance distance is the length along a highway at one or more railroad or light rail transit tracks, measured from the highway stop line, warning device, or 12 feet perpendicular to the track centerline, to 6 feet beyond the track(s) measured perpendicular to the far rail, along the centerline or edge line of the highway, as appropriate, to obtain the longer distance. For Four-Quadrant Gate systems, the minimum track clearance distance is the length along a highway at one or more railroad or light rail transit tracks, measured either from the highway stop line or entrance warning device, to the point where the rear of the vehicle would be clear of the exit gate arm. In cases where the exit gate arm is parallel to the track(s) and is not perpendicular to the highway, the distance is measured either along the centerline or edge of the highway, as appropriate, to obtain the longer distance.” The MTCD is indicated by the shaded area:



Clear Storage Distance – is defined in OMUTCD Section 1A.13 as: “…the distance available for vehicle storage measured between 6 feet from the rail nearest the intersection to the intersection stop line or the normal stopping point on the highway. At skewed grade crossings and intersections, the 6-foot distance shall be measured perpendicular to the nearest rail either along the center line or edge line of the highway, as appropriate, to obtain the shorter distance. Where exit gates are used, the distance available for vehicle storage is measured from the point where the rear of the vehicle would be clear of the exit gate arm. In cases where the exit gate arm is parallel to the track(s) and is not perpendicular to the highway, the distance is measured either along the centerline or edge line of the highway, as appropriate, to obtain the shorter distance.” The following diagram illustrates this clear storage distance:

Design Vehicle – is defined in OMUTCD Section 1A.13 as “the longest vehicle permitted by statute of the road authority (State or other) on that roadway.” ORC Section 5577.05(C)(6) prescribes the maximum length of combination vehicles as sixty five feet.

Diagnostic Team – is defined in 23 U.S.C. 646.204(d) as: “a group of knowledgeable representatives of the parties of interest in a railroad-highway crossing or group of crossings.” The diagnostic team includes the highway agency or authority with jurisdiction, the regulatory agency with statutory authority and the railroad. Their charge is to determine the need and selection of traffic control devices at a highway-rail grade crossing in accordance with ORC Sections 4511.61, 4513.40, 4907.47, 4907.471, 4907.476, 4907.48, 4907.49, 4907.52 and 4955.33. Constant Warning Time System – is defined as a type of equipment designed to detect both the motion of a train and the approximate speed of the train in order to predict the arrival of the train at the crossing and to provide a relatively uniform warning time in accordance with a pre-set value. Indicator Panel – is defined as an electrical enclosure, mounted on the traffic signal support, strain pole, or similar location, that provides a visual indication of railroad preemption status.



Interface Panel – is defined as an electrical device panel located within the traffic signal cabinet that contains all necessary relays, connectors, wires and labels to implement the required interconnection between traffic signal equipment and railroad crossing equipment; this includes devices used to drive the indicator panel. Railroad Dwell Interval – is defined as the component of highway traffic signal preemption that follows the Track Clearance Green Interval for the duration of the train movement through the highway-rail grade crossing. Railroad Warning System – is defined as the active traffic control devices and train detection circuitry installed at a highway-rail grade crossing for the purpose of warning road users of the approach of a train. Track Clearance Green Interval – is defined as one interval of the highway traffic signal preemption sequence when the signal faces which control the movement of motor vehicles through the Clear Storage Distance and the Minimum Track Clearance Distance display CIRCULAR GREEN and GREEN ARROW indications. Train Control Signal – is defined a signal operated by the railroad that is analogous to a roadway traffic signal. It informs a train operator when to proceed, stop, slow down, etc. 804-3 Railroad Preemption of Traffic Signals 804-3.1 General

Railroad preemption is a special control mode designed to clear motor vehicles from, or prohibit motor vehicles from entering, a portion of the roadway known as the Minimum Track Clearance Distance (MTCD), which crosses over or is in close proximity to railroad tracks or rails. Railroad tracks or rails include those rails operated in semi-exclusive rights-of-way for the use of light rail vehicles or streetcars.

The preemption and interconnection of traffic signals with a railroad warning system requires a systems approach in order to ensure the proper functioning of the individual systems as a combined system. No single standard system of traffic control devices is universally applicable for all highway-rail grade crossings. The need for preemption and its corresponding operation is developed through a diagnostic team which conducts an engineering study to determine the appropriate system. See Section 804-4 for a standardized design guideline to define the requirements of the interconnection between the railroad and traffic signal controller. See Form 896-1 for a standardized form to transmit preemption functional and time requirements to the railroad company.

804-3.2 When to Preempt OMUTCD Section 8C.09, states:

“If a highway-rail grade crossing is equipped with a flashing-light signal system and is located within 200 feet of an intersection or midblock location controlled by a traffic control signal, the traffic control signal should be provided with preemption in accordance with Section 4D.27.” “Coordination with the flashing-light signal system, queue detection, or other alternatives should be considered for traffic control signals located farther than 200 feet from the highway-rail grade crossing. Factors to be considered should include traffic volumes, vehicle mix, vehicle and train approach speeds, frequency of trains, and queue lengths.”



The specific distance between the railroad and the adjacent intersection which establishes the need for preemption has varied over the years. The 1948 Manual on Uniform Traffic Control Devices recommended interconnection where the distance was within 500 to 1000 feet. In 1961, the distance was shortened to the present 200 feet. The predominant factor to consider when determining whether or not to preempt is the queue length. Field observation of queue length during critical traffic periods can provide guidance. Queue arrival and dissipation studies or capacity analysis may be beneficial in further refining the observed queue lengths. The vehicle usage over the crossing may also form a basis to determine whether to preempt or not. Vehicles which haul hazardous materials, school buses or public transportation vehicles may further influence the decision to preempt at locations which fall just outside the maximum distance and queuing length observations.

804-4 Highway-Rail Grade Crossing Warning System Interconnection Design Guidelines

804-4.1 Purpose

The purpose of this design guideline is to define the required interface between a highway-rail

grade crossing warning system and a traffic control signal for the purpose of railroad preemption. It

defines the standard interface to provide the operation as specified by the Ohio Rail Development

Commission (ORDC) for each interconnected highway-rail grade crossing.

804-4.2 Operation The interface shall provide the following functions:

1. Advance Preemption. This circuit will notify the traffic signal controller of an approaching train

prior to the operation of the active warning devices.

2. Simultaneous Preemption. This circuit will notify the traffic signal controller of an approaching

train at the point the active warning devices begin their operation. This circuit is commonly

known as an “XR” circuit.

3. Island Occupied. This circuit will notify the traffic signal controller of the occupancy of the

island circuit by the train.

4. Gate Down. This circuit will notify the traffic signal controller when the gate(s) controlling

access to the track(s) is lowered to within 5 degrees of horizontal.

5. Gate Up. This circuit will notify the traffic signal controller when all gates at the crossing are

raised. This circuit is commonly known as the “GP” circuit.

6. Traffic Signal Health. This circuit will notify the railroad warning system whenever the traffic

signal has entered conflict flash or the power has failed.

804-4.3 Traffic Signal Interface

804-4.3.1 Traffic Signal Controller

The traffic signal controller shall be provided with either a relay based interface, a solid state

interface using DC isolator cards or a serial data interface using the IEEE 1570 protocol. If not

specified on the plans, a basic controller unit with a cabinet relay interface shall be provided.

The interface shall function as follows:



1. Advance Preemption. This circuit will notify the traffic signal controller of an approaching

train prior to the operation of the active warning devices. Two relays or both channels of

an isolator card are required. The railroad will return a normally open and a normally

closed circuit. Preemption will be initiated when the normally closed circuit opens. The

normally open circuit closes when preemption is initiated indicating the proper functioning

of the supervision circuit.

2. Simultaneous Preemption. This circuit will notify the traffic signal controller of an

approaching train at the point the active warning devices begin their operation. One relay

or one channel of a DC isolator card is required. The railroad will return a normally closed

circuit which opens when the railroad warning devices begin to operate.

3. Island Occupied. This circuit will notify the traffic signal controller of the arrival of the train

at the island circuit. One relay or one channel of a DC isolator card is required. The

railroad will return a normally closed circuit which opens when the train occupies the

island circuit.


access to the track(s) is lowered to within 5 degrees of horizontal. One relay or one

channel of a DC isolator card is required. The railroad will return a normally open circuit

which closes when the gate(s) controlling access over the crossing approaching the

intersection is lowered.

5. Gate Up. This circuit will notify the traffic signal controller when all gates at the crossing

are raised. One relay or one channel of a DC isolator card is required. The railroad will

return a normally closed circuit which opens when all the gates at the crossing are raised.

6. Traffic Signal Health. This circuit will notify the railroad warning system whenever the

traffic signal has entered conflict flash or the power has failed. This is an output from the

traffic signal controller to the railroad control equipment. It shall be 12 VDC which is output

whenever the traffic signal is not in flash and power is on. If the traffic signal is in flash or

the power is off, the output shall be 0 VDC. A simple method is to use a 12V transformer

and rectifier connected to the coil of the signal bus control relay or mercury contactor. The

intent is that the traffic signal health output will be de-energized even if the signal bus

contactor output remains closed. The output should be fused.

7. An output shall be included to provide for the operation of illuminated blank-out signs. The

signs shall be illuminated whenever the controller unit is in railroad preemption as

indicated by an output circuit provided by the controller unit. A solid state relay, Crydom

part number D1210 or equal mounted on the interface panel or unused loadswitch

element shall be used to illuminate the blank-out signs.

8. If a relay interface is provided, the relays connected to the railroad equipment shall

operate at 24 VDC. A 24 VDC isolated NEMA TS-2 power supply (such as Reno A&E

Model CPS-TS2) shall be provided and connected to the preemption isolation panel

assembly to power the relays and indicator lights. The power supply outputs shall not be

connected to any other voltage source or common such as logic ground, ac neutral or

earth ground. The power supply shall be capable of providing enough current to

simultaneously energize all of the relays and illuminate all of the indicators at maximum

temperature plus a 20 percent de-rating. The power supply shall be capable of providing a

carryover of 50ms at full load. The input and the output of the power supply should be



appropriately fused and the power supply should be fully isolated with no grounded

conductors. 24 VDC relays should be Magnecraft 788XBXM4L-24D or equal which

include an internal LED indicator. In this document, “or equal” means a pin-for-pin

interchangeable equivalent. 120 VAC relays shall be Magnecraft 788XBXM4L-120A or

equal which include an internal LED indicator. Relays shall be installed in an appropriate

socket, Magnecraft 70-463-1 or equal. Hold down clips, Magnecraft 16-1351 or equal

shall be provided for each relay. Adequate terminals, numbered or labeled and identified

on the wiring diagram shall be provided for all field connections and all internal

connections. The relays and terminals shall be mounted on a suitable aluminum panel

located in an area accessible for inspection and connection.

9. If a solid state interface is provided, the isolator cards shall be mounted in a separate 4

position rack. Three Model 242 DC isolator cards and a 24 VDC, 5 Amp power supply

card shall be provided. The power supply shall be capable of providing carryover in the

event of primary power loss for a minimum period of 35 ms at full rated load. Adequate

terminals, numbered or labeled and identified on the wiring diagram shall be provided for

all field connections and all internal connections. The terminals shall be mounted on a

suitable aluminum panel located in an area accessible for inspection and connection. The

rack shall be mounted in an area suitable for viewing of the card mounted indicators and

for removal and insertion of cards. The input configuration should be as follows:

Card 1 Input 1 – Advance Preempt Normally Closed

Card 1 Input 2 – Advance Preempt Normally Open

Card 2 Input 1 – Simultaneous Preempt

Card 2 Input 2 – Island

Card 3 Input 1 – Gate Up

Card 3 Input 2 – Gate Down

804-4.3.2 Nomenclature and Terminals

The nomenclature and terminals shall be as indicated on the interface panel wiring diagram.

Terminals shall utilize a “cage-clamp” design such as manufactured by WAGO Corporation

or equivalent. Terminals which provide “side wipe” connections or set screws are not

acceptable. See Subsection 804-4.6 for additional information regarding terminal numbers.

804-4.3.3 Harness The appropriate harness (MS D, C11 or other) for the specific controller unit provided shall be

furnished and connected to the preemption interface panel.

804-4.3.4 Preemption Input Test Switch Panel A preemption input test switch panel with six test switches shall be provided and mounted in a

convenient location within the controller cabinet. The railroad circuits shall be connected

through the test switch panel to directly simulate the input from the railroad. Each switch shall

be labeled exactly as indicated below by use of a silk screened legend or an engraved plastic

plate. Rub-on, adhesive or other markings which are not permanent are not acceptable. The

following switches shall be provided: 1. Advance Preemption Test – This switch shall be DPDT and arranged such that the up

position is normal and the down position is test. When up, the two advance preemption



circuits from the railroad should pass through the test switch. When down, the advance

preempt normally closed circuit shall be open and the advance preemption normally open

circuit shall be closed. This switch shall be labeled “ADVANCE PREEMPTION NORMAL”

for the up position and “ADVANCE PREEMPTION TEST” for the down position.

2. Simultaneous Preemption Test – This switch shall be SPDT and arranged such that the

up position is normal and the down position is test. When up, the simultaneous preemption

circuit from the railroad shall pass through the test switch. When down, the simultaneous

preemption circuit shall be open. This switch shall be labeled “SIMULTANEOUS

PREEMPTION NORMAL” for the up position and “SIMULTANEOUS PREEMPTION

TEST” for the down position.

3. Island Circuit Test – This switch shall be SPDT and arranged such that the up position is

normal and the down position is test. When up, the island preemption circuit from the

railroad shall pass through the test switch. When down, the island preemption circuit shall

be open. This switch shall be labeled “ISLAND CIRCUIT NORMAL” for the up position and

“ISLAND CIRCUIT TEST” for the down position.

4. Gate Up Test – This switch shall be SPDT and arranged such that the up position is

normal and the down position is test. When up, the gate up preemption circuit from the

railroad shall pass through the test switch. When down, the gate up preemption circuit

shall be open. This switch shall be labeled “GATE UP CIRCUIT NORMAL” for the up

position and “GATE UP CIRCUIT TEST” for the down position.

5. Gate Down Test – This switch shall be SPDT and arranged such that the up position is

normal and the down position is test. When up, the gate down preemption circuit from the

railroad shall pass through the test switch. When down, the gate up preemption circuit

shall be closed. This switch shall be labeled “GATE DOWN CIRCUIT NORMAL” for the

up position and “GATE DOWN CIRCUIT TEST” for the down position.

6. Traffic Signal Health Test - This switch shall be SPDT and arranged such that the up

position is normal and the down position is test. When up, the traffic signal health preemption circuit to the railroad shall pass through the test switch. When down, the traffic signal health preemption circuit shall be open. This switch shall be labeled “TRAFFIC SIGNAL HEALTH NORMAL” for the up position and “TRAFFIC SIGNAL HEALTH TEST” for the down position.

804-4.3.5 Indicator Panel

An indicator panel shall be provided for mounting on the signal support or strain pole adjacent

to the controller. The indicator panel shall be fabricated from stainless steel and shall be

provided with 6 LED indicators.

1. Indicator lights shall be 1-inch diameter, waterproof with LED lamps meeting NEMA 4X

and IP66 requirements. Units shall be Dialight series 556 or approved equivalent.

Indicators shall be provided for the following:

Advance Preempt – Normally Closed – Green (556-1604-304F)

Advance Preempt – Normally Open – Yellow (556-1704-304F)

Simultaneous Preempt – Red (556-1504-304F)

Island – Orange (556-1904-304F)

Gate Up – Blue (556-1804-304F)



Gate Down – White (556-1004-304F)

2. The indicators shall be arranged in two columns of three. The arrangement, when viewed

from the front shall be:

AP – NC GU AP – NO GD SP ISL

3. Enclosure shall be Hoffman A8064C HEMC SS or equivalent NEMA 4X stainless steel

enclosure with stainless steel or aluminum internal terminal panel. Suitable terminal strips

shall be provided on the internal terminal panel for connection of the indicators to the

home run cable to the controller.

4. A hub plate or suitable bracket shall be provided on the bottom of the enclosure for

mounting and cable entry.

5. The indicator panel shall be attached to the signal support or strain pole nearest the grade

crossing control equipment cabinet or bungalow and shall be oriented so as to face the

railroad cabinet or bungalow so as to provide an unobstructed view of the indicators. The

indicator panel shall be mounted no less than ten feet above roadway level. The indicators

should also be so located so as to provide a minimal visibility to roadway users at or

approaching the intersection.

6. A seven conductor IMSA signal cable shall be installed between the indicator panel and

the interface panel.

7. The indicator common shall be connected to the +24 VDC output from the preemption

rack power supply or from the relay panel power supply.

8. Where DC Isolator cards are used for the interconnection interface, the indicators shall be

connected to their respective isolator inputs from the railroad circuits.

9. Where a relay isolation panel is used for the interconnection interface, the indicators shall

be connected to their respective relay inputs from the railroad circuits in accordance with

the typical wiring diagram.

7. A warning label shall be provided and installed by the agency responsible for the

maintenance of the traffic signal on the interior of the cabinet indicating the

interconnection of the two systems (see Figure 898-1)..

804-4.4 Traffic Signal Controller Unit

As of this release, three traffic signal controller units have been approved for use with railroad

preemption within Ohio. These units and possible interfaces are indicated in the following table:

Controller Unit Relay

Interface Solid State Interface

IEEE 1570 Interface

2070 L with City of LA TSCP V X

(With C11)

X

(With C11) X

Econolite ASC/3 X X NO



Siemens with SEPAC X X NO

X = Allowable Any other controller unit proposed for use with railroad preemption must be provided to ODOT for

extensive testing prior to consideration. The controller unit must include all equipment necessary to

fully exercise all of the preemption functions.

Refer to TEM Part 4 for additional controller unit requirements.

804-4.5 Railroad Interface

Unless otherwise specified, the railroad bungalow shall be provided with suitable relay contacts

and one control relay for the interface. The interface shall function as follows:

1. Advance Preemption. This circuit will notify the traffic signal controller of an approaching train

prior to the operation of the active warning devices. One Heel-Front-Back contact on the

Advance Preempt relay is required.

2. Simultaneous Preemption. This circuit will notify the traffic signal controller of an approaching

train at the point the active warning devices begin their operation. One Heel–Front contact on

the XR or equivalent relay is required. The Advance Preemption Relay Heel shall be

connected to the Simultaneous Preemption Relay Heel. The XR circuit shall be connected in

such a way that the Simultaneous Preempt Relay can never be down with the XR relay up.

This is commonly circuited by having the XR relay as a repeater of the preempt relay.

3. Island Occupied. This circuit will notify the traffic signal controller of the arrival of the train at

the island circuit. One Heel–Front contact is required.


access to the intersection over the track(s) is lowered. The normal position of this relay is down

until the gate down contact closes and picks up the relay. One Heel–Front contact of the gate

down relay is required. If more than one gate controls access over the crossing approaching

the intersection, then both mechanisms must indicate that they are lowered prior to picking up

the gate down relay. In accordance with AREMA 16.30.10, the Gate Down Heel-Front contact

shall be wrapped by a Heel-Back contact on the Island relay.

5. Gate Up. This circuit will notify the traffic signal controller when all gates at the crossing are

raised. One Heel–Front contact on the GP or equivalent relay is required.

6. Traffic Signal Health. This circuit will notify the railroad warning system whenever the traffic

signal has entered conflict flash or the power has failed. The railroad will provide a traffic

signal health relay which will normally be energized by this input. One contact of the advance

preempt relay shall be in series with the XR relay. This contact shall be wrapped by a Heel–

Front on the traffic signal health relay. Whenever the traffic signal health relay is down, the

operation of the railroad warning devices shall be extended by the advance preemption time.

If requested by the railroad, consideration will be given to the use of the IEEE 1570 serial data

interface in lieu of the relay interface described above in this Subsection 804-4.5. Final

determination as to the use of the IEEE 1570 jointly rests with ORDC and ODOT based on the

availability of a traffic signal controller unit which supports the IEEE 1570 interface.



The railroad, in accordance with its standards, may elect to provide a junction box on the exterior of

the signal bungalow or as a stand-alone enclosure near the edge of the right-of-way for the

termination of the interconnect cable. As an alternate, the railroad may coordinate installation with

the traffic signal installer to bring the interconnect cable directly into the railroad bungalow for

termination on the terminal board or within a faraday cage.

If a traffic control signal is located on both sides of the crossing and two independent

interconnection circuits are required, the railroad shall supply isolated relay contacts for each

interconnection circuit. All functions may share common relays with the exception of “Gate Down.”

Additionally, two traffic signal health relays will be required, one for each intersection.

If the railroad has determined to provide non-motion sensing circuits such as DC or Style C circuits,

then a means should be provided to cancel the operation of the warning devices and

corresponding preemption request in the event a train stops within the approach to an

interconnected warning system. Either an automatic timing circuit or a cutout and a restart

pushbutton switch shall be provided for use by the train crew. Operating rules shall require the

crew to operate the cut-out or allow the timing circuit to deactivate the warning devices and

preemption operation whenever the train is stopped not occupying the crossing for a period of five

minutes or greater. If a cut-out pushbutton switch is provided, its operation shall be canceled by

operation of the restart pushbutton switch or the occupancy of the island circuit. A cut-out circuit or

automatic timing circuit shall not function if the island is occupied.

A warning label shall be provided and installed by the railroad on the interior of the bungalow

indicating the interconnection of the two systems (see Figure 898-1).

Upon completion of the project and release of the as-built drawings, the railroad shall furnish a

copy of every sheet of the signal wiring diagrams which contain information necessary to verify the

approach length, minimum warning time, advance preemption time and maximum authorized train

speed applicable to the project at the time the project is placed in-service. The plan sheets should

be provided in .pdf format to the ORDC project manager.

804-4.6 Interconnect Cable

The interconnect cable between the railroad and the traffic signal controller shall be a 6 pair #19

gauge IMSA 19-2 or REA PE-39 communication cable in accordance with ODOT CMS Item

732.19.

The interconnect cable shall be continuous without splices between the two systems.

The assignment of the conductors shall be as follows:

Pair Wire Color Function Interface Panel

Terminal Number

1 1 Blue Advance Preempt Normally Closed Positive 1

1 2 White Advance Preempt Normally Open Positive 2

2 1 Orange Simultaneous Preempt Positive 3

2 2 White Preempt Negative 4

3 1 Green Island Positive 5

3 2 White Island Negative 6



4 1 Brown Gate Down Positive 7

4 2 White Gate Down Negative 8

5 1 Slate Gate Up Positive 9

5 2 White Gate Up Negative 10

6 1 Blue Traffic Signal Health Positive 11

6 2 Red Traffic Signal Health Negative 12

804-4.7 Testing

Testing on the railroad interconnect shall be performed in accordance with ODOT CMS 632.28

Parts A, C, D, E and F. Personnel from the railroad will be required to assist in the completion of

tests C, D, E, and F to assist in isolating the cable in the railroad enclosure and then performing

functional testing.

804-4.8 Working Drawings

The preemption interface panel and associated equipment in the traffic signal controller shall

comply with ODOT CMS Item 625.06.



805 RUMBLE STRIPS

Rumble strips (see TEM Chapter 1415) may be used as an audible and vibratory warning device at highway-rail grade crossings after all other appropriate standard traffic control devices have been considered. Rumble strips at highway-rail grade crossings shall be designed in accordance with the guidelines established by the Office of Traffic Engineering (OTE) and the Office of Roadway Design (available upon request from OTE).



830 PLANNING / PROGRAMMING

830-1 General This Chapter is intended to provide planners and designers assistance in the planning phase of a project or work assignment. There are a lot of tools available for temporary traffic control and this information is intended to help in making the choice of which tool to use and how. As needed, information will also be provided about other considerations involved in the planning phase. See Chapter 804 for additional information and guidelines on railroad preemption of traffic signals and interconnection with grade crossing warning systems. 830-2 Grade Separation Program The Railroad Grade Separation Program was developed to mitigate the impacts of increased rail traffic in Ohio. It is governed by a subcommittee of the Transportation Review Advisory Council (TRAC). The subcommittee appointed a technical advisory group (TAG) comprised of representatives from ODOT, ORDC, PUCO, the Ohio Emergency Management Agency (OEMA), FHWA, and the CSX and Norfolk Southern Railroads. This committee prepares the initial feasibility study. This in turn is ranked by the subcommittee of the TRAC for final acceptance. Details of the process are found in the Railroad Grade Separation Program Policies and Procedures Manual (Section 895-3). 830-3 New or Upgrade Highway Traffic Signal Projects When a new or upgrade project for a highway traffic signal is planned and it has been determined that preemption is required, it is of the utmost importance to involve the railroad as quickly as possible. In virtually every case, the implementation of preemption will require additional warning time above the minimum time of twenty seconds required by OMUTCD Section 8C.08 from the railroad. The project planner or designer should coordinate with the ORDC and/or PUCO to establish a diagnostic team inspection at the proposed location (see Section 804-2). Once the diagnostic inspection has been held and the preemption operation and timing requirements have been established, the railroad will be able to provide an estimate of cost for the work required (see Section 804-3 and 804-4). The following items should be considered in the project planning process: 1. The time required for the estimate process may take several months. In many cases, once the

diagnostic team inspection has been completed, the railroad will be required to determine the impact not only at the proposed project location, but also at adjacent crossings. In many cases, the diagnostic team will be required to view the railroad requirements on a “corridor” basis. This may be necessitated based on the number of crossings impacted and the type of train detection circuits already in place.

2. The railroad shall determine the types of circuitry which will operate properly based on the

condition of the track. In certain cases, track conditions or crossing surfaces may create limitations which will prohibit the use of certain train detection systems. This may necessitate the need to provide special design considerations to address proper operation of the train detection system.

3. The cost required to provide the required warning time may greatly exceed the cost of the traffic

signal or roadway project. 4. When facing significant costs to provide the required warning time, changes at the intersection may

play a significant role in reducing project costs. 5. Railroad signal material procurement and construction time may be lengthy. Generally, these

projects must be completed within nine months, but in certain cases, site specific needs create delays outside the control of the railroad which may further add to the time required to complete



the project. 6. Remember that crossing consolidation and closure may be an alternative. 7. Any new traffic signal or upgrade to an existing traffic signal that is or will be interconnected shall

require the installation of a backup power system to maintain operation of the traffic signal during periods of commercial power outage. The backup power supply should have sufficient capacity to assure continued operation of the traffic signal for a minimum period of 8 hours.

830-4 New or Upgrade Railroad Warning System Projects When a new or upgrade project for a railroad warning system is planned, the ORDC or PUCO, upon notification of the project, will contact the appropriate roadway authority to schedule a diagnostic team inspection (see Section 804-2). If a new or upgrade project for a railroad warning system is proposed by another government agency or a private developer, the agency or developer must establish contact with the ORDC and PUCO to initiate the diagnostic team inspection. If, during the course of the diagnostic team inspection it is determined that a highway traffic signal may require preemption, a plan will be developed to establish the need for preemption and identify any traffic signal upgrades which may be necessary. Some of the items which will be considered will include the following:

1. What are the capabilities of the existing traffic signal equipment and is it capable of providing preemption operation in accordance with the requirements of the TEM?

2. Is the current phasing and signal operating plan capable of displaying the track clearance

green interval?

3. Are the vehicular signal faces capable of displaying the appropriate indications during the preemption sequence?

4. What provisions exist for pedestrians within the intersection?

5. Are turn prohibitions required during preemption?

6. Does the proposed operation create a “yellow trap” condition during the transition into preemption?

7. Are geometric changes to the intersection necessary or desirable?

8. Should certain pedestrian movements be prohibited?

9. Can U-Turn movements add additional delay to the effective beginning of the track clearance green interval?

See Section 804-3 and 804-4 for additional information railroad preemption of traffic signals and highway-rail grade crossing warning system interconnection design guidelines, respectively.



840 DESIGN INFORMATION

840-1 General Design information regarding highway-rail grade crossings is found in the L&D Manual Volume One, Section 700, and in AASHTO’s A Policy on Geometric Design of Highways and Streets, Chapter 9. For projects involving railroads, it is important to get early coordination with the railroad companies and ORDC. Additional information about the coordination needed when planning new or upgrade highway signal projects and railroad system warning projects is provided in Chapter 830. See Chapter 804 for additional information, including definitions, and guidelines on railroad preemption of traffic signals and interconnection with grade crossing warning systems. 840-2 Design of Locations with Railroad Preemption

840-2.1 General When planning the design of a highway traffic signal which is to be interconnected with and preempted by a railroad warning system, the following items must be addressed and resolved prior to completion of the design. See Chapters 804 and 830 for more information. Also, definitions of some of the terms used here are provided in Section 804-2.

840-2.2 Railroad Warning Devices

The following information is required from the railroad in order to proceed with a railroad warning device project. Ideally, the request for this information should be submitted to the railroad prior to the diagnostic team meeting. Having this information available at the time of the diagnostic team inspection will expedite the data collection process and aid in the process or determining the proper train detection circuitry (see Chapters 804 and 830).

1. The railroad company responsible for the design and maintenance of the railroad warning

system. ORDC can provide this information upon request.

2. The Maximum Authorized Speed (MAS) of trains using the line.

3. Do passenger trains use the line or are there plans to add passenger service to the line?

4. If passenger trains use the line, is there a station stop in place or planned for 3 miles either side of the crossing?

5. Is the line equipped with train control signals?

6. If the answer to the above question is yes, how are the signal controls handled? a. Overhead line circuits

b. Underground cable

c. Coded track

d. Data radio

7. Does the line support the installation of constant warning time circuitry?

8. Are there any overlapping grade crossings located within 2 miles either side of the proposed



location? 9. If the answer to the above questions is yes, provide the following information:

a. The name and DOT number of each overlapping crossing

b. The type of train detection circuitry installed at each overlapping crossing

c. The frequencies of all equipment installed at any overlapping crossing.

d. The Minimum Warning Time provided for each overlapping crossing.

10. Are there any wayside signals located within 2 miles either side of the proposed location?

11. Are there any control points or interlockings located within 2 miles either side of the proposed

location?

12. If the answer to the above question is yes, identify the following: a. The configuration and signal layout at the interlocking.

b. If the interlocking is a railroad crossing at grade, how is the interlocking controlled?

c. What is the maximum speed through any diverging routes?

d. Are there any pending changes to the control point or interlocking which would impact this

project?

13. Are there any switching moves or unusual operating issues conducted within 2 miles either side of the proposed location?

14. What is the Gate Delay time? The gate delay time is the number of seconds the flashing lights

operate prior to the descent of the gate.

15. What is the Gate Descent time? The gate descent time is the period of time in seconds required for all gates controlling the movement of motor vehicles into the MTCD moving toward the signalized intersection to be fully lowered.

840-2.3 Highway Traffic Signal

The public agency responsible for the design and maintenance of the highway traffic signal must be consulted in order to address and resolve numerous issues regarding the design and operation of the highway traffic signal and the intersection geometrics. The following items should be addressed with the public agency as a part of the preemption planning process. Having this information available prior to the diagnostic team inspection will expedite the process (see Chapters 804 and 830).

1. The proposed phasing for the traffic signal may require modification in order to provide proper

operation during the preemption sequence. The following items must be addressed regarding the traffic signal phasing: a. Are the movements over the track capable of being operated independently of other

movements? If the signal is proposed to operate with concurrent movements crossing the track, separate phases must be provided even though the movements normally occur simultaneously.

b. Are pedestrian movements planned? If so, have pedestrian pushbuttons or other pedestrian detectors been provided for every pedestrian movement?



2. The proposed signal displays for the traffic signal may require special considerations. The following items must be addressed regarding the traffic signal displays:

a. During the track clearance green interval, a GREEN ARROW shall be displayed to motor

vehicles exiting the MTCD. This indication is required even if it is not displayed during the normal or non-preempted sequence.

b. In many cases, the entrance into the track clearance green interval will create a yellow trap condition. Refer to Section 403-8 for additional information regarding yellow trap.

c. Have provisions been made to address turning movements toward the tracks during

preemption? OMUTCD Section 8B.08 states:

“At a signalized intersection that is located within 200 feet of a highway-rail grade crossing, measured from the edge of the track to the edge of the roadway, where the intersection traffic control signals are preempted by the approach of a train, all existing turning movements toward the highway-rail grade crossing should be prohibited during the signal preemption sequences.”

Engineering judgment is required to determine the appropriate measures to be used to address turning movements toward the tracks. As a general rule, the shorter the CSD, the greater the need to prohibit turning moves toward the tracks during preemption. The intent is to keep the intersection clear of motor vehicles during the preemption sequence.

Turning movements may be prohibited during preemption through the use of illuminated LED “blank-out” signs, additional railroad warning devices, protected only signal displays, or a combination of any of these devices. Any blank-out sign used to establish a turn restriction during railroad preemption should contain the illuminated word TRAIN in 4- inch white letters below the symbol.

d. The use of countdown pedestrian signals shall be evaluated to determine their operation

during the transition into preemption. If the RWTT provided does not provide for the full Pedestrian Change interval, then strong consideration should be given to using conventional non-countdown displays or other means to provide notification to pedestrians regarding the approach of the train.

3. Use of Pre-Signals - The design of Pre-Signals is specified in Section 840-3. It should be

noted that pre-signal use may decrease the capacity of the signalized intersection. As a result, careful consideration should be given to the use of pre-signals and the overall impact on the intersection. Improper use of pre-signals may result in driver disregard and a decrease in credibility. The use of pre-signals at a highway-rail grade crossing shall be considered if one or more of the following conditions is satisfied. a. Where the CSD is less than 80 feet and there is little opportunity for a design vehicle to

make a right turn on red due to geometric limitations or infrequent gaps in conflicting traffic.

b. Where frequent numbers of vehicles using the crossing are carrying hazardous materials.

c. On a multi-lane approach where overhead obstructions or other physical constraints limit the number of railroad flashing lights to less than one pair per lane.

4. Use of Queue Cutter Signals - The use of queue cutter signals (see Section 840-4) should be

considered as an alternative to interconnection and preemption where the CSD exceeds 450 feet. A queue cutter signal is installed and located in a manner similar to a pre-signal, but it is



not connected to or operated as a part of the signalized intersections. A queue cutter signal requires its own controller and vehicle detection system. The length of the queue determines when the queue cutter signal changes. Its normal state is green. Only when a train approaches or a queue forms approaching the MTCD does the indication change to red. Queue cutter signals and their associated control systems require careful planning and design to assure that appropriate fail safe principles are used. A fail-safe vehicle detector (Reno A&E U-1400 or equivalent) must be used to provide a self-check function to verify proper queue detector operation. This is due to the fact that the queue cutter is the only device which will keep the queue clear of the tracks when a train approaches. A queue cutter signal is interconnected with the railroad warning system for advance preemption. Queue cutter signals may also be effective in other applications where a downstream restriction creates a queue to form toward the MTCD.

5. The operation and timing of the traffic signal require consideration in order to avoid conflicts with the preemption operation. The following items should be considered:

a. If the traffic signal is proposed to operate in a coordinated system, preempted locations should be designed so as not to utilize pedestrian recall on any phases. In addition, the use of rest in walk should never be implemented.

b. The traffic signal timing information is necessary in order to calculate the preemption time requirements. This information must be available prior to the diagnostic team inspection.

c. In order to properly implement railroad preemption, special functionality is required in

the controller unit and the operating software. Refer to Section 403-10 for additional information regarding the controller unit railroad preemption functionality.

840-2.4 Intersection Geometrics and Configuration

Certain intersection geometrics can have a significant impact on the design and installation of railroad warning devices as well as some of the time required for preemption. The following items should be considered as a part of the geometrics and configuration of the intersection:

1. The length of crosswalks is a key component in determining the right-of-way transfer time

(RWTT). Because the pedestrian change interval is a function of crosswalk length, it can be costly to provide the required period of time. Consideration should be given to the potential use of pedestrian refuge islands or right turn channelization where crosswalks exceed 60 feet in length.

2. The crosswalk parallel and closest to the railroad track is the most critical in the transition to track clearance green. Strong consideration should be given to the elimination of this crosswalk in order to reduce the RWTT.

3. Another factor in determining RWTT is the amount of minimum green time provided during the

transition into track clearance green. The appropriate design and placement of vehicle detection should be provided in order to minimize the need for extended minimum green intervals.

4. The length of the gates used at highway-rail grade crossings is limited to 32 feet. Where

multiple lanes are proposed at a highway-rail grade crossing, consideration should be made to providing center islands in order to permit the installation of a median gate. This will reduce the overall length of a single gate arm.

5. The right turn radius can also have a significant impact on gate arm length. Where a large

radius is required, consideration should be given to the installation of a separate channelized right-turn lane with a separate gate in order to reduce gate arm length.



840-3 Design of Pre-Signals Pre-signals can be used to stop motor vehicles approaching the intersection before such vehicles reach the railroad crossing. Pre-signals are typically considered only when one or more of the conditions listed in Section 840-2.3, item 3, is satisfied. Use of pre-signals for longer clear storage distances must carefully consider the violation of driver expectancy for stopping traffic well in advance of the normal stopping point for the intersection as well as the inherent inefficiency of pre-signal operation. The placement of pre-signals does not replace the need for a proper track clearance green interval. 1. The stop line location must be 40 feet in advance of the pre-signals to comply with OMUTCD

Section 4D.15. Pre-signals can be located upstream or downstream from the railroad crossing. Locating the pre-signals downstream from the crossing (between the crossing and the intersection) should be considered so that the stopping point for the pre-signals is the same as the stopping point for the railroad warning device(s). As a general rule, driver compliance with a downstream pre-signal is greater than driver compliance with an upstream pre-signal. Note that at locations where the angle of the tracks is skewed or more than two tracks exist, the placement of a downstream pre-signal may create a condition where drivers stop on the tracks for the pre-signal. This generally occurs where the stop line to pre-signal face distance is greater than 70 feet. In this case, either an upstream pre-signal should be provided or the pre-signal should be eliminated.

2. The pre-signals and support structures shall be located to maintain visibility of the railroad flashing

lights. In some cases, downstream pre-signals may require the use of horizontally aligned signal heads.

3. As required by OMUTCD Section 8C.09, a STOP HERE ON RED (R10-6) sign shall be installed

near the pre-signal or stop line. 4. Whenever a pre-signal is utilized, one or more NO TURN ON RED (R10-11) sign(s) is/are

required. A pre-signal identifies a separate stopping point on the roadway in advance of the signalized intersection requiring the prohibition of right turn on red.

5. The pre-signal intervals should be progressively timed with the downstream signal intervals to provide adequate time to clear vehicles from the track area and the downstream intersection with each cycle of the normal traffic signal operation. Vehicles that are required to make a mandatory stop at the crossing, such as school buses and vehicles hauling hazardous materials, should be considered when determining the progressive timing to ensure they will not be stopped within the minimum track clearance distance. Vehicle detection for the through phase(s) should be placed on the roadway in advance of the pre-signal. Consideration should be given to installation of vehicle detection within the clear storage distance to extend the pre-signal green clearance interval to prevent vehicles from being trapped within the minimum track clearance distance.

6. Left-turn phasing considerations shall be carefully evaluated when using pre-signals. In many cases the pre-signals will need to include signal faces for the through phase as well as the left- turn phase if leading left-turn phasing is used. The use of a lagging left-turn phase to provide the progressive clearance interval may require that the left turn opposing the track clearance be a protected only left-turn phase in order to prevent a yellow trap condition. As an alternative, the opposing movements may be split.

7. The downstream traffic signal faces at the roadway intersection that controls the same approach

as the pre-signal shall be programmable-visibility heads or louvered as appropriate to prevent vehicles stopped at the railroad crossing stop line from seeing the distant green signal indication during the track clearance interval. The downstream signal heads shall be mounted on rigid supports or tethered to maintain the effectiveness of the programmed visibility or louvers.



840-4 Design of Queue Cutter Signals A queue cutter signal is a traffic signal installed at a highway-rail grade crossing in a manner similar to a pre-signal. A queue cutter signal differs from a pre-signal in that it is not connected to or operated as a part of a downstream signalized intersection. The queue cutter signal is a form of coordination between the railroad warning system and a downstream signalized intersection which operates independently of the intersection. The use of a queue cutter signal is beneficial whenever the normal advance preemption time is so lengthy that it is not practical to obtain. Generally, a queue cutter signal is installed where the CSD exceeds 450 feet. It is interconnected with the railroad warning system with a 3 to 5 second advance preemption time. A queue cutter signal consists of the following elements: 1. A “safety critical” vehicle detection system using self check capabilities shall be used to activate the

queue cutter control system. This system is necessary due to the fact that the queue cutter signal is the only device keeping the MTCD clear of vehicles and the system must be known to be operating at all times.

2. The vehicle detection system shall detect the buildup of a queue of vehicles before the queue

reaches the MTCD. This requires placement of the detectors sufficiently far enough downstream from the crossing to detect the lack of a gap, provide for a yellow change interval and permit a design vehicle which has lawfully crossed the stop line (entered at end of yellow) to have adequate room to cross over and clear the MTCD.

3. A queue cutter signal control system shall have battery backup which is capable of operating for a

period of time equal to or greater that the associated railroad warning system. 4. Any fault of the queue cutter system shall result in a flashing red display.

5. The stop line location must be 40 feet in advance of the queue cutter signals to comply with

OMUTCD Section 4D.14. Queue cutter signals can be located upstream or downstream from the railroad crossing. Locating the queue cutter signals downstream from the crossing (between the crossing and the intersection) should be considered so that the stopping point for the queue cutter signals is the same as the stopping point for the railroad warning device(s). As a general rule, driver compliance with a downstream queue cutter signal is greater than driver compliance with an upstream queue cutter signal. Note that at locations where the angle of the tracks is skewed or more than two tracks exist, the placement of a downstream queue cutter signal may create a condition where drivers stop on the tracks for the queue cutter signal. This generally occurs where the stop line to queue cutter signal face distance is greater than 70 feet. In this case, an upstream queue cutter signal should be used.

6. The queue cutter signals and support structures shall be located to maintain visibility of the railroad

flashing lights. In some cases, downstream queue cutter signals may require the use of horizontally aligned signal heads.

7. A STOP HERE ON RED (R10-6) sign shall be installed near the queue cutter signal or stop line.



850 CONSTRUCTION

This Chapter has been reserved for information regarding construction related information regarding highway-rail grade crossing situations.

860 MAINTENANCE / OPERATIONS

This Chapter has been reserved for information regarding maintenance and/or other operational information regarding highway-rail grade crossing situations.



880 RESEARCH

880-1 General This Chapter is reserved for information about pertinent research regarding traffic control at highway-rail grade crossing. 880-2 Buckeye Crossbuck The final report on this experiment, evaluating the Buckeye Crossbuck at public, passive highway-rail grade crossings, was issued in December 2000. For copies of the report contact the Office of Research Development. A recommendation to amend the MUTCD to include the Buckeye Crossbuck as an alternate design was submitted to FHWA. However, FHWA is considering other changes to the signing at highway-rail grade crossing signing and it was decided that the Buckeye Crossbuck would not be included in the MUTCD.



895 REFERENCE RESOURCES

895-1 General Various reference resources that may be useful have been noted in Sections 193 and 194. Additional specific resource references are noted herein. 895-2 Related ORC References The following are some specific ORC references that may be helpful regarding Railroad Crossings: 4511.61 Stop Signs at grade crossings 4511.62 Drivers duties relating to railroad grade crossings 4511.63 Vehicles required to stop at grade crossings; exempt crossings 4511.64 Slow-moving vehicles or equipment crossing railroad tracks 4513.40 Warning sign before safety device at street crossing 4955.33 Crossbuck signing; additional reflective signs; experimental signs 4955.36 Removal of obstructive vegetation at crossings 5515.06 Procedure to remove buildings or other obstructions near railroad crossings 895-3 Railroad Grade Separation Program Policies and Procedures Manual As noted in Section 193-23, the Railroad Grade Separation Program Policies and Procedures Manual provides information on the program history, an overview of the annual process to select projects, the initial feasability study process, project development activities, and financial and project management 895-4 Railroad-Highway Grade Crossing Handbook As noted in Section 193-11, the Railroad-Highway Grade Crossing Handbook, published by FHWA, presents guidelines for prioritizing improvements to railroad-highway grade crossings and information on the various types of improvements that can be made to the crossing. The handbook also provides guidelines to determine which crossing improvement is the most cost effective for the site. 895-5 AREMA Communication & Signal Manual The AREMA Communication and Signal Manual of Recommended Practice is a valuable resource to gain additional understanding and insight into the design and operation of railroad warning systems. This publication is available through AREMA (American Railway Engineering and Maintenance-of-Way Association) from the organization’s website at http://www.arema.org/.



896 Forms Index

896-1 Highway-Rail Grade Crossing and Timing As noted in Subsection 804-3.1, Form 896-1 is issued by the Ohio Rail Development Commission (ORDC) to establish railroad configuration and timing requirements for the railroad.



Form 896-1. Highway-Rail Grade Crossing Warning System Railroad

Configuration and Timing Requirements

OHIO DEPARTMENT OF TRANSPORTATION OHIO RAIL DEVELOPMENT COMMISSION HIGHWAY-RAIL GRADE CROSSING WARNING SYSTEM INTERCONNECTION RAILROAD CONFIGURATION AND TIMING REQUIREMENTS

Railroad: __________________________________________________________ DOT: __________________________ Crossing Name: ___________________________________________________________ Date: __________________________ Issued By: __________________________________________________________ This crossing warning system is proposed to be interconnected with an adjacent highway traffic control signal. In some cases, the warning system may be interconnected with two highway traffic control signals, usually one on each side of the grade crossing. The #2 interconnect circuits are only required if indicated below. The purpose of this document is to advise the railroad of the number of interconnection circuits required and the type and timing requirements of each circuit. The railroad should refer to the Chapter 804 of the ODOT Traffic Engineering Manual (TEM), Subsection 804-4.5 for details concerning the requirements of the interface to be provided by the railroad.

TYPE OF INTERCONNECTION INTERCONNECT #1 INTERCONNECT #2

ADVANCE *

SIMULTANEOUS

NOT REQUIRED

* Advance Preemption Time Per AREMA 3.3.10



898 Figures Index

898-1 Example of a Interconnection Warning Label As noted in Subsections 804-4.3.4 and 804-4.5, Figure 898-1 displays an example of the warning label used on the inside of the signal controller cabinet and the railroad bungalow to indicate the interconnection between the two systems.



Form 898-1. Example of an Interconnection Warning Label

WARNING!WARNING!WARNING!WARNING!

Highway-Rail Grade Crossing Warning System

and Highway Traffic Signals

are Interconnected.

BEFORE MODIFICATION is made to any operation which

connects to or controls the timing of an active railroad warning system and/or timing and phasing of a traffic signal the appropriate party(ies) shall be notified and, if necessary, a joint inspection conducted.

U.S. DOT/AAR Crossing Number: __________________________

1. Highway Agency: ____________________________________

Phone Number: _____________________________________

2. Railroad: ___________________________________________

Phone Number: _____________________________________

3. Other: _________________________________________

Phone Number: __________________________________

(An alternate might also use florescent orange or yellow background with black letters.)

800 RAIL GRADE CROSSINGS Traffic Engineering Manual TABLE OF CONTENTS … · 2014-01-17 · 800...

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