Glossary of Terms


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Ganger
Term for person responsible for maintenance of a section of track.

Legacy
Disciplines: Infrastructure
Gangway
The intercar walking surface provided between adjoining passenger vehicles.

Preferred
Disciplines: Rolling Stock
Gantry
A signal structure spanning one or more tracks and having two or more points of support.

Preferred
Disciplines: Infrastructure, Train Control
Gantry Crane
An overhead crane spanning one or more rail tracks and roadway to allow transfer of loading from a road vehicle, or a rail wagon, to another wagon. The crane may be either running on its own rails or be rubber tyred to allow it to move around a terminal. Often referred to as RTG (rubber tyred gantry) or straddle crane.

Preferred
Disciplines: Operations
Gauge (track)
The distance between the inside running (or gauge) faces of the two rails, measured between points 16 mm below the top of the rail heads.

Preferred
Disciplines: Infrastructure
Gauge Conversion
The process of changing the track gauge from one gauge to another, e.g. broad gauge to standard gauge.

Preferred
Disciplines: Infrastructure
Gauge Corner
Transition surface separating the rail running surface from the rail side.

Preferred
Disciplines: Infrastructure
Gauge Face
The inner side of the running rail head, i.e. the side of the rail head where the track gauge is measured and could be contact by the wheel flange.

Preferred
Disciplines: Infrastructure
Refer to Running Face.
Alternative
Disciplines: Infrastructure
Related Term: Running Face
Gauge Face Angle
The angle between a line perpendicular to the sleeper plane (i.e. the plane of the track) and the line tangent to the rail gauge face where wheel flange contact occurs.

Preferred
Disciplines: Infrastructure
Gauge Indicator
Gauge indicators are a special form of signalling route indicators which indicate to the driver on a dual gauge track, which gauge of track he is being signalled towards.

Regional
Disciplines: Train Control, Operations
Gauge Point
The point on the side of the rail head 16mm beneath the top surface of the rail at which track gauge is measured.

Preferred
Disciplines: Infrastructure
Gauge Side (track)
The side of the rail within the track gauge.

Preferred
Disciplines: Infrastructure
Gauge, Guard Rail
The distance between the guarding face of a guard rail and running edge of a running rail, measured across the track at right angles to the running edge.

Preferred
Disciplines: Infrastructure
Gauntlet (track)
A section of track where the two lines of track overlap so that one rail of each track is within the rail gauge of the other.

Preferred
Disciplines: Infrastructure
GCP
Grade Crossing Predictor


Disciplines:
Abbreviated term for 'grade crossing predictor', a microprocessor-controlled system that is deployed to continually monitor the approach to level crossings. It applies a constant a.c. signal to the track and measures the level of the resulting voltage. This varies with the approaching train which alters the track impedance. The voltage and its rate of change are used to determine the train speed, train arrival time and to activate the crossing protection equipment at the appropriate time.
Alternative
Disciplines: Rolling Stock, Electrical
General Inspections
Essentially visual inspections but may include some elementary site testing and measurement. They should include the requirements of a patrol inspection in addition to inspection of all readily visible elements of the infrastructure and elements known to contain critical defects.

Preferred
Disciplines: Infrastructure, Electrical
General Purpose Flat Wagon
A wagon with a full width substantially flat deck, without side walls and with or without stanchions, bulkheads and other load support and restraint systems.

Preferred
Disciplines: Rolling Stock
General Train Inspection
An examination conducted by appropriately qualified employees (normally locomotive drivers) at those times and locations where other staff qualified to conduct a Full Train Inspection inspection are not available.

Preferred
Disciplines: Operations
Geographical Interlocking
An interlocking in which standard pre-assembled modules are provided for each signalling function, arranged and electrically interconnected in a geographical manner.

Regional
Disciplines: Train Control, Electrical
Refer to Free-wired Interlocking.
Alternative
Disciplines: Train Control, Electrical
Related Term: Free-wired Interlocking
Geographical Panel
Control panel reproducing schematically the position of the tracks and the aspects of signals etc., with their respective control switches or buttons.

Preferred
Disciplines: Electrical, Train Control
Give Up Seat
A person must vacate a seat which is designated for elderly or disabled passengers on a rail or road vehicle if asked to do so by an authorised person. The holder of a student concession ticket must vacate a seat on a rail or road vehicle on which there are no empty seats if asked to do so by an authorised person.

Other
Disciplines: ALL Disciplines
Glued Insulated Joint
An insulated rail joint in which the rails, fishplates and components are glued.

Preferred
Disciplines: Infrastructure
Gold Flashed Contact
Contact surfaces treated with a thin film of gold to provide a reliable, low resistance, clean electrical contact, particularly in low voltage circuits.

Regional
Disciplines: Train Control, Electrical
Goods Line
A running line that is not required to be signalled to the standard required for passenger trains.

Regional
Disciplines: Train Control
GPL
Ground Position Light Signal


Disciplines:
Abbreviated term for 'ground position light signal'.
Alternative
Disciplines: Train Control
Grabrail
A short rail that is generally placed in a horizontal or vertical orientation to steady or assist a person carrying out a movement or action.

Preferred
Disciplines: Rolling Stock
Grade
The rate of slope of the surface of the track in the direction of its length.

Preferred
Disciplines: Infrastructure
Grade Control Device
A wagon fitting which slows the release of the brakes. It has three positions: EX for 'exhaust' which means the brakes are operating normally, IP which is an intermediate delay position and HP which is maximum delay.

Preferred
Disciplines: Rolling Stock, Operations
Grade Separation
The crossing of a track by another track, roadway or pedestrian pathway by an underbridge or overbridge, rather than crossing at the same elevation.

Preferred
Disciplines: Infrastructure
Gradient
A measure of the rate at which the railway is inclined (rising or falling).
Gradients are signed +ve (rising) or -ve (falling) in respect of the direction of travel.

Preferred
Disciplines: Infrastructure
Grading Rings
Buried earth electrode system which encircles the structure to be protected. The purpose of the grading ring is to prevent the rise of hazardous step and touch voltage potentials.

Preferred
Disciplines: Electrical, Infrastructure
Graduated Cant Plate
A plate under the rail which changes rail cant from 1:20 on open track to zero cant at crossing work over 3 adjacent timbers. They are marked A (1:30), B (1:40) or C (1:80) to indicate the cant.

Preferred
Disciplines: Infrastructure
Green (aspect)
Displayed by a colour light signal, indicates to the driver that, in three or four aspect signalling, the next signal will be displaying a proceed aspect.
Also see Two Position / Two Aspect Signalling.

Regional
Disciplines: Train Control, Operations
Green Card
A card placed in the waybill clip of a vehicle to notify all concerned that repairs are required on that vehicle, however the vehicle may remain in traffic until it is operationally practicable to effect those repairs.

Preferred
Disciplines: Rolling Stock
Refer to 'defect card'.
Alternative
Disciplines: Rolling Stock
Groove
The flangeway gap between the running edge and check of a tramway rail, crossing or installation.

Regional
Disciplines: Infrastructure
Groove, Deep (crossing Design)
Crossingwork design with a sufficiently deep flangeway depth which ensures wheel tread contact with the running surface in the wheel transfer area.

Preferred
Disciplines: Infrastructure
Groove, Shallow (crossing Design)
Crossingwork design with a shallow flangeway depth which provides for wheel flange bearing and thus no contact of the wheel tread with the normal running surface.

Preferred
Disciplines: Infrastructure
Gross Mass
Nominal total mass of rolling stock including maximum
payload, provisioning, maximum service capacity of crew and passengers and wheels at nominal new diameter.

Preferred
Disciplines: Rolling Stock
Gross Tonne Kilometre
Gross tonne kilometres is a measure calculated by multiplying the gross weight of a train (ie the weight of the locomotives and wagons plus the payload) by the distance travelled.

Preferred
Disciplines: ALL Disciplines, Operations
Ground Fault Detector
A detector similar to a slip detector but installed vertically to detect vertical displacement of the ground, including ground heave due to related ground movement.

Regional
Disciplines: Train Control, Infrastructure
Ground Frame
A small track side interlocking machine used for manual points operation.

Preferred
Disciplines: Operations, Infrastructure
Ground Position Light Signal (GPL)
A position light signal mounted at ground level.

Regional
Disciplines: Train Control
Ground Shunt Signal
A shunting signal mounted at ground level.

Regional
Disciplines: Train Control
Ground Switch Panel
A ground frame which uses only switches and/or buttons as operating devices.

Regional
Disciplines: Train Control
GSM-R
Global System for Multiple Communications - Railways


Disciplines:
Global system for mobile communications - railways.
Regional
Disciplines: Train Control
Guaranteed Power Supply
See Secure Power Supply.

Alternative
Disciplines: Electrical
Guard
A qualified worker on a passenger train who carries out safeworking duties and is responsible for the safety and supervision of passengers. Where required, the guard assists the driver in the management of the train and its associated equipment.

Preferred
Disciplines: ALL Disciplines, Operations
Guard Edge
The side of the guard rail head which makes contact with the backs of the wheels.

Preferred
Disciplines: Infrastructure
Guard Rail
A rail (inside or outside the running rail) used to restrain lateral movement of a derailed wheelset. Used to protect structures or control the lateral movement of the wheelset on bridges or in other higher risk situations.

Preferred
Disciplines: Infrastructure
Guardrail
A rail or series of rails acting as an obstacle or barrier to a person falling from an elevated position, or to moving to a position of danger. A guardrail may also serve as a single or multiple handrail.

Preferred
Disciplines: ALL Disciplines, Rolling Stock
Guards Indicator
A lunar white light in a case inscribed Guards indicator' provided on the platform which, when illuminated, indicates to the guard of a train that the signal at the departure end of the platform is showing a proceed indication.

Regional
Disciplines: Train Control
Guards Keys
Interlocking keys, with bow handles, for securing interlocking frames at intermediate sidings on double lines.

Regional
Disciplines: Train Control, Operations
GWA
Genesee and Wyoming Australia


Disciplines:
The Rail Infrastructure Manager for the Tarcoola to Darwin standard gauge network.
Preferred
Disciplines: ALL Disciplines