A block which must not be occupied by more than one train.
Accelerometer
A device which measures a trains rate of speed change.
Active Dynamic Braking
Using the traction motors as generators whose output is dissipated in a massive resistor bank. The effect being to consume the trains momentum in generating electricity.
Adhesion
The amount of pulling or retarding force a wheel is capable of exerting on the rail without slipping or spinning. The base coefficient of friction between the wheel and the rail are the determining factors. These factors are affected by the load on the wheel, wheel and rail condition and external factors such as oil, rust & weather.
Air Flow Indicator
An instrument that measures the air flow through the automatic brake valve to the brake pipe.
Alertness Device
A device that initiates a penalty brake application when the engineer does not maintain the required frequency of movement. - A "deadman" type of safety device.
Angle Cocks
Valves controling air flow from one car to another on the air hoses between those cars.
Alignment Control Couplers
Specially equipped couplers that limit lateral movement and reduce lateral forces on the track. These couplers minimize rail turnover, wheel climb, and jackknifing.
Articulated Car:
A car constructed by permanently connecting two or more platforms with an articulated joint (two platforms share a common truck).
Automatic Block Signal
A block signal which is activated by track circuit or in conjunction with interlocking or controlled point circuits. This block signal automatically indicates track condition and block occupancy.
Automatic Block Signal System (ABS)
A system in which the use of each block is governed by an automatic block signal, cab signal, or both.
Automatic Cab Signal System (ACS)
A system that allows cab signals and the cab warning whistle to operate automatically.
Automatic Train Stop (ATS)
A device on an engine which will cause a penalty application of the brakes if the engineer fails to acknowledge a cab signal change to a more restrictive indication.
"B" End of Car
The end where the hand brake is located, unless otherwise identified.
Bad Order
When a defective car is found by a car inspector, he tacks a small card labeled "bad order" in bold lettering on or near the door of the car. That car may not be moved from the terminal where the inspection occurred until the necessary repairs are made.
Belt Line
A railroad with trackage within and/or around a city, operating as a pickup, delivery and transfer facility for truck lines and industrial plants.
Bleeder
The valve by which air is bled from the auxiliary air tank reservoir on a car.
Blended Braking
Using a combination of service braking and dynamic braking.
Block
A length of track with defined limits on which train movements are governed by block signals, cab signals, or Form D's.
A lever, plug, ring, or other method of controlling that restricts the operation of a switch or signal.
Block Signal
A fixed signal displayed to trains at the entrance of a block to govern use of that block.
Block System
A block or series of consecutive blocks within ABS, ACS, CTC, or interlocking limits.
Blue Signal
A clearly distinguishable blue flag, blue light, or blue tag by day, or blue light or blue tag by night. When displayed, it signifies that workers are on, under, or between equipment.
Bolster Stop
A device that, when properly installed, limits the lateral movement of a drawbar.
Bolt-Lock Switch
A hand-operated switch equipped with a pipe connected locking device that is designed to shunt the signal system before the switch points are operated.
Brake Cylinder Release Valve
The valve that initially bleeds brake cylinder pressure. If held open, it will bleed auxiliary and emergency reservoir pressures.
Brake Pipe Gradient
The difference in brake pipe pressure between the locomotive (or source of supply) and the rear car of the train. Inverse Gradient: The temporary condition when the brake pipe pressure is higher at the rear of the train than at the head end of the train (for example, at the beginning of a service brake application). False Gradient: The temporary gradient that exists when the system is less than fully charged (for example, the exaggerated difference between the head end and rear end after a release). Normal Gradient: The gradient that exists when the system is fully charged.
Branch Line
A line serving one or more stations beyond the point of junction with the main or another branch line.
Buff Force
Compressive coupler forces that occur during a slack bunched condition.
Bulletin Order (BO)
A publication used to notify employees of changes to rules, procedures, or other instructions affecting the movement of trains. BO's are issued periodically by the designated officer.
Cab Signal
A signal that is located in the engine control compartment which indicates track occupancy or condition. The cab signal is used in conjunction with interlocking signals, and with or in lieu of block signals.
Cab Signal System (CSS)
A system that allows cab signals and the cab warning whistle to operate.
Camp Car
Any on-track vehicle, except a wreck train, that is used to house railroad employees.
Car Shop Repair Track Area
One or more tracks within an area in which the testing, servicing, repairing, inspecting, or rebuilding of cars is under the exclusive control of mechanical department personnel.
Classification Tracks
A system of tracks designed to facilitate classification switching by providing for the arrangement of freight cars according to their kinds, contents and destinations.
Conductor (Cndr)
A crew member on an engine who's primary duty does not include operation of the train. The conductor is required to inspect the train if a detector is tripped.
Conductor and Engineer (C&E)
The abbreviation is used as the designation of a recipient on a Form D when the Form D is conveyed or delivered to a train whose movement will be governed by the Form D.
Consist
The make-up of a freight train by types of cars and their contents.
Control Operator
Employee assigned to operate a CTC or interlocking control machine or authorized to grant track permits.
Control Station
The Dispatcher's office, or the location where the Operator is on duty, from which remote control signal appliances or switched are operated.
Controlled Point (CP)
A station designated in the Timetable where signals are remotely controlled from the control station.
Controlled Siding (CS)
A circuited siding in which both ends are controlled and governed by signals under the control of a Dispatcher or Operator.
Controlled Signal
A fixed signal, capable of displaying Stop indication, that is controlled by a Dispatcher or Operator.
Crossover
A combination of two switches connecting two adjacent tracks. When lined, the switch combination allows movements to cross from one track to the other.
Crow's Nest
The cupola or box-like structure raised above the roof of a caboose from which a trainman may see along the train while it is in motion.
Current of Traffic
The assigned direction of movement on a Rule 251 main track, as specified in the Timetable.
Cycle Braking
The process of applying, releasing, and reapplying train brakes to control speed without completely recharging the train brake system.
Dead Engine Device (DED)
A device near the locomotive control valve used when a locomotive unit is handled dead-in-train (hauled like a car).
Dead-in-Train
Hauling locomotive(s) in a train without the MU cable and air hoses coupled and cut in.
Demurrage
Tariff charges assessed for detaining freight cars beyond their specified time limit.
Derail
A track safety device designed to guide a car off the rails at a selected spot as a means of protection against collisions or other accidents.
Dispatcher (Dspr)
The person in charge of all movements with their designated region (i.e. the Pittsbugh East Dspr is in charge of the trackage from Alto to Conpit). The Dspr is also in charge of issuing Form D's.
Distant Signal
A fixed signal used to govern the approach of a train to a home signal.
Disturbed Track
A section of passable track that has a temporary speed restriction imposed because various defects or track maintenance has affected the integrity of the track.
Division
A geographical unit of operation in charge of a superintendent under whose direction the three essential functions coming under "operations" are carried out. These functions are the maintenance of way and structures, maintenance of equipment, and transportation of freight and passengers.
Division Notice (DN)
A publication issued periodically by the designated officer, which contains instructions or information which do not affect the movement of trains.
Draft Force
Pulling force (tension) on couplers and draft gear during a slack-stretched condition.
Draft Gear
A cushioning device that transmits draft or buff forces between the coupler and the car or locomotive.
Draw Bar Forces
The longitudinal forces at the couplers between cars or locomotives. The forces may be draft or buff, depending on train operation.
Dual Control Switch
A power-operated switch also equipped for hand operation.
Effective Locking Device
A switch padlock that is vandal or tamper resistant, and can be unlocked only by the class, group, or craft of employees that applied it.
Effective Securing Device
A device applied to secure a manually operated switch or derail for the protection of Roadway Workers. The device must be vandal and tamper resistant, and designed to be applied, secured, uniquely tagged, and removed only by the class, group, or class of employees for whom the protection is provided.
Electrically Locked Switch
A hand-operated switch equipped with an electrically controlled device that restricts the movement of the switch.
Emergency Application
A reduction in brake pipe pressure at a rate sufficient to cause control valves to move to the emergency position.
End of Train Telemetry Device (ETD)
A system of components that determines the rear car brake pipe pressure and transmits that information to the display on the head-of-train telemetry device (HTD).
Engine (Eng)
A unit or combination of units propelled by any form of energy, and operated from a single control, used in train or yard service. The word "engine" may also be used to identify control cars.
Engine Servicing Track Area
One or more tracks within an area in which the testing, servicing, repairing, inspecting, or rebuilding of engines is under the exclusive control of mechanical department personnel.
Engineer (Engr)
The member of the crew designated and qualified to operate a train over the territory to be traversed.
Extra Board
A list of employees who may be assigned to train crews (1) when extra trains are run, (2) when regular crews have not had sufficient rest time before they can legally be required to return to duty, or (3) when relief men are required on regular crews.
Extra Gang
The crew of track laborers assigned to maintenance work at various points on a railroad right-of-way. These employees may live in camp (bunk) cars where they are provided lodging and meals at a nominal cost.
Extra Train
A train not designated by a Timetable schedule.
Fixed Signal
A signal at a fixed location that affects the movement of a train.
Flagman
Usually, the brakeman assigned to duties at the rear end of the train.
Flares (Fuses)
Combustible torches which burn (red, yellow or green) for ten to fifteen minutes as warning signals to other trains when touched off and placed or thrown on the ground by train service employees.
Foreman (Frm)
A person who is in charge of a Roadway Crew. A Frm is authorized to control train traffic through a section of trackage which has been designated by Form D as obstructed for maintenance.
Form D
See Movement Permit Form D.
Form D Control Ssystem (DCS)
A block system, signaled or non-signalled, in which the movement of trains outside of yard limits is authorized by Form D.
Freight (Frt)
Any type of consist other than persons which makes up the load of a train.
Frog
The "X" shaped portion of a switch or diamond; also an implement to rerail car wheels.
General Order (GO)
A publication used to summarize changes to the Timetable and other instruction manuals. GO's contain revision pages for the Timetable, and are issued periodically by the designated officer.
Grade
The ratio of elevation gained or lost per distance traveled expressed as a percent "%". The base is 100 Ft. so a 1% grade represents a 1Ft. elevation change in 100Ft. of travel. Light Grade = 1% or less Heavy Grade = 1% to 1.8% Mountain Grade = 1.8% or greater Cresting Grade = A long ascending Grade that changes with enough magnitude to require a change in train handling procedures.
Head Man
The freight train brakeman who rides in the locomotive cab.
Home Signal
A fixed signal governing the entrance to an interlocking or controlled point.
Hot Box
Overheated wheel journal or wheel bearing which usually causes journal packing to burn and smoke.
Hump Yard
A switching yard on an incline where, after movements by the engine, the cars are shunted by gravitational pull to their destination in a yard.
Indepentent Application and Release Control
Controls independent brakes on multiple locomotives from a single control.
Industrial Track (Ind)
A track other than a main track, running track, siding, or yard track, upon which movements must be made at Restricted Speed.
Interchange
A track on which various cars are delivered or received from one railroad to another.
Interlocking (Int)
An interconnection of signals and signal appliances such that their movements must succeed each other in a predetermined sequence, assuring that signals cannot be displayed simultaneously on conflicting routes.
Interlocking Appliances
The parts of an interlocking that are capable of movement (i.e. switches, derails, locks, movable point frogs, movable bridges, etc.)
Interlocking Limits
The trackage between the opposing home signals of an interlocking.
Interlocking Signals
The fixed signals of an interlocking.
Interlocking Station
A location from which an interlocking is operated.
Junction (Jct)
A location designated by the Timetable where two or more railroad lines converge.
Light Engine Move
Movement of engines from one location to another, as an Extra, to balance out power requirements between terminals, or serve as Emergency Power for a train that died, or serve as pushers returning from a push.
Mainline
That part of a railroad exclusive of switch tracks, branches, yards and terminals.
Main Track
A track designated by the Timetable upon which train movements are authorized by ABS, DCS, or interlocking.
Maintenance of Way (MW or MOW)
A location designated by Form D where work is being done by Roadway Crews.
Manifest
Fast freight usually made up of merchandise, perishables or livestock.
Marker
A reflector flag, light, or other highly visible marking device, in the red-orange-amber color range, affixed to the rear of a train to indicate that the train is complete. Markers may be communicating or non-communicating devices. As an added note, rear helper engines may serve as markers.
Mile Post (MP)
A white sign with black numbers on which the distance from a designated point is displayed. Also, MP may designate any location along the trackage given to the tenth of a mile.
Motor Car
A motor-driven railway inspection or work car which rides on the rails and is operated by maintenance of way employees to minimize time spent traveling while on duty. NOTE: Motor-Driven actually means driven by a small gasoline or diesel engine (not in the locomotive sense).
Movable Point Frog
A frog with a moving alignment allowing open flangeway for train movement.
Movement Permit Form D
A form containing written authorization(s), restriction(s), or instruction(s), issued by the Dispatcher to specified individuals.
Number (No.)
Used to designate the number of a track.
Occupied Camp Car Signal
A white circular sign with black letters, which must be supplemented by a white light at night. When displayed, it signifies that employees are in, around, or in the vicinity of camp cars.
Operator (Opr)
The person in control of a designated section of track who is accountable to the Dispatcher for movement of trains.
Overhead Bridge (OH)
Any bridge whether railroad, automotive, or pedestrian, which crosses above the trackage.
Passenger (Psgr)
A person other than crew which is being transported by a train. Also, is a designation given to any train whose primary consist is people.
Pilot
An employee assigned to a train or track car when the Engineer, Conductor, or Track Car Driver is not qualified on the physical characteristics or the operating rules of the territory traversed.
Plant
A slang term for an interlocking.
Push-Pull Train
A passenger train with a MU or control car at either end.
Retarder Yard
A switching yard in which the movement of cars, after they are released from a locomotive, are controlled by an employee in a control tower by means of stationary brakes that press on the inside of the wheel flanges of the cars - as like automotive disc brakes but in this case the rail itself is the opposing "brake shoe."
Return Movement
The movement of an uncoupled engine, engines, or leading portion of a train, directed back toward the remaining stationary portion of the same train.
Reverse Movement
A movement opposite the direction previously authorized.
Roadway Worker
Any employee of a railroad, or of a contractor to a railroad.
Rule G
Railroad work rule against the use of intoxicants.
Rules-in-effect
The specific operating rule or group of operating rules that govern the use of tracks, as designated in the Timetable.
Running Track
A designated track on which movements may be made by signal indication or at Restricted Speed under the authority of an employee designated in the Timetable.
Schedule
The part of the Timetable that prescribes direction, number, frequency, and times for movement of designated trains.
Scheduled Train
A train designated by Timetable schedule.
Semi-Automatic Switch
A hand-operated switch that is designed to be trailed through in either position. The switch points stay in the position last used.
Siding
A track adjacent to a main track, and is used for meeting or passing other trains.
Signal Aspect
The signal appearance, which conveys an indication as viewed either (1) from the direction of an approaching train, or (2) on the cab signal display unit in the engine control compartment.
Signal Indication
The required action conveyed by the aspect of a signal.
Slide Fence
A fence which is placed along trackage to warn of rock slides. If the fence is activated, it changes the aspect of the signals governing that block to Stop.
Speed Control
A device on an engine which will cause a penalty application of the brakes if the engineer fails to reduce the train's speed to the speed required by the cab signal indication.
Speeds
Normal Speed: The maximum authorized speed. Limited Speed: For freight trains, not exceeding 40 MPH. For passenger trains, not exceeding 45 MPH. Medium Speed: Not exceeding 30 MPH. Restricted Speed: Within interlocking, not exceeding 15 MPH. Outside interlocking, not exceeding 20 MPH. Slow Speed: Not exceeding 15 MPH.
Sperry Car
Railroad car used by Sperry Rail Service to detect weakened or cracked rails.
Spotting Cars
Switching freight cars to a specified location for loading and unloading.
Spring Frog
A frog used on infrequently used switches with the diverging route flangeway closed to reduce wear on the point of the frog. The wing rail is spring loaded to allow equipment to pass through on the diverging route.
Spring Switch
A hand-operated switch that is designed to trail through in either position. The switch points automatically return to their original position after being trailed through.
Station
A place designated on the station pages of the Timetable by name.
Tariff
A published schedule showing rates, fares, charges, classification of freight, rules, and regulations applying to various kinds of transportation and incidental services.
Temporary Block Station (TBS)
A manned station that is established by Bulletin Order or Form D to control the movement of trains.
Three-Step Protection
A procedure used for the protection of workers going on, under, or between cars. (1) Apply the brake. (2) Center the reverser. (3) Put the generator field switch in the OFF or OPEN position.
Timetable
A printed booklet that contains schedules and/or special instructions affecting the movement of trains.
Tons of Operative Brake (TOB)
The measurement calculated by dividing the gross trailing tonnage of a train (not including the locomotives) by the total number of cars with operative brakes.
Track Barricade
A designated sign or obstruction fastened to a track which prevents access to the track.
Track Car (TC)
Equipment, other than trains, operated on a track for inspection or maintenance. Track cars may not shunt track circuits.
Train
An engine with or without cars, displaying a marker.
Trainmaster
An executive officer who supervises train service operations on one or more divisions or on part of a division. He also supervises the operation of trains at terminals and in yard service.
Turn-Around
A train operated from a terminal to an intermediate station and returned to that terminal in one work shift.
Undergrade Bridge (UG)
Any point where the trackage crosses above any railroad, automotive, or pedestrian right of way, or stream.
UNDESIRED EMERGENCY
An undesired emergency application of a train's air brake system. (Also known as "Dynamiter" or "Kicker".)
WAYBILL
A document for handling and accounting for a shipment of freight.
WAY CAR
A box car from which LCL (Less than carload lot) shipments are loaded and unloaded at various towns.
YARD
A system of tracks used for the making up of trains and the storing of cars.
YARD LIMITS
The main track area between Yard Limit signs as designated in the Timetable. Movements of trains must be made at Restricted Speed within Yard Limits.
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