Glossary

AROC / WROC (Auckland Rail Operations Centre / Wellington Rail Operations Centre)
The centres that coordinate and monitor rail operations in the Auckland and Wellington regions.

ATIS (Automated Track Inspection System)
Rail vehicle with technology that automatically monitors track condition and identifies areas that may need maintenance.

Auckland One Rail / Transdev
Rail operators that manage and deliver passenger train services under contract.

Axle load
The weight on any one axle (tonnes).

Ballast
The layer of crushed rock beneath and around railway tracks that helps hold the track in place and provides drainage.

Ballast cleaner
A machine that removes dirt and debris from ballast, helping maintain track drainage and stability.

Bogie
A twin-axle wheelset or "truck".

 Bogie Wagon
A rail wagon with twin axle wheel sets.

BOL (Block of Line) / Rail closure
A planned period when part of the rail line is closed to train services so maintenance or construction work can be completed safely.

BRT (Buses Replacing Trains)
Bus services provided when trains cannot operate, usually during planned maintenance or unexpected disruptions.

CAR / TAR (Corridor Access Request / Track Access Request)
Formal approvals that allow work to be carried out within the rail corridor or on railway tracks.

Clearance gauge
The maximum permitted dimensions of the rail vehicle and load.

Consist
The set of wagons or carriages which form the train.

Crossover
A section of track that allows trains to move from one track to another.

CWR
Continuous Welded Rail.

DEMU
Diesel Electric Multiple Unit: a two passenger car set in which one car is diesel electric powered.

Derailment
A derailment of a train that has been made up, tested and departed from the originating station.

Destressing
Heating and refastening of rail.

DM / UM (Down Main / Up Main)
The names used for the main railway tracks in each direction of travel on a rail line.

DMU
Diesel Multiple Unit: a two passenger car set in which one car is diesel powered.

Double tracked
A railway line with two parallel tracks, allowing trains to travel in both directions simultaneously.

Dropped track
A section of railway track where the track level has sunk or settled, affecting track geometry and potentially requiring speed restrictions or maintenance.

ECMT
East Coast Main Trunk line between Hamilton and Kawerau.

EM80
Rail vehicle that automatically records track geometry and notes exceedances.

EMU
Electric Multiple Unit. A two or three passenger car set in which one car is electrically powered.

ESO (Electrical Safety Officer)
A qualified person responsible for managing electrical safety around rail infrastructure.

FLB
Flashing lights and bells.

Formation
The earthworks on which the track is laid.

Gauge (track gauge)
The distance between the rails on the railway track (1067 mm or 3 ft 6 inches on NZ rail).

Heat 40
A rail safety measure introduced during extremely hot weather, when track temperatures can affect rail performance and train speeds may need to be reduced.

Heat buckling
Distortion of track alignment under high temperature conditions.

Heritage Charter Services
A train service organised for or by rail heritage enthusiasts. Heritage Operator means rail enthusiasts organising and operating such a service.

Hi-Rail Vehicle (HRV)
A road vehicle fitted with retractable rail trolleys such that it can be driven along the track and can also be driven on or off track at level crossings or other suitable places.

LE (Locomotive Engineer)
The person responsible for driving and operating a train.

Line haul
That part of the transport task that is between terminals (distinguishing from the aggregation and distribution at each end of the journey).

LX (Level Crossing)
A place where a road, pedestrian path, or cycleway crosses a railway line. Level Crossings are the only places where the public are permitted to cross the rail corridor.

Marshalling
Arranging wagons in the correct order for making up trains.

Midland Line
The East-West rail line between Greymouth and Rolleston (south of Christchurch).

MMP (Metro Maintenance Plan)
A planned programme of regular night maintenance activities designed to keep the metropolitan rail network safe and reliable with limited access windows.

MNPL
The route of railway from Marton to New Plymouth.

Mobile Track Maintenance Vehicle (MTMV)
Tampers, regulators, spot re-sleepering group, ballast cleaner, track evaluation car, self-propelled cranes and heavy hi-rail vehicles exceeding an unladen weight of 20 tonnes.

MNL (Main North Line)
The route of railway from Picton to Christchurch on the South Island.

MRL
Manukau Rail Link.

MSL (Main South Line)
The route of railway from Lyttelton to Invercargill on the South Island.

Mudspot
An area where water and fine material have weakened the track foundation, affecting track stability and ride quality.

NAL (North Auckland Line)
The route of railway from Westfield Auckland to Otiria in Northland.

Narrow Gauge
Distance between rails of less than 1.435 metres; in the case of the company, a gauge of 1.067 metres.

Net Tonne-Kilometres (NTK)
The sum of the tonnes carried multiplied by the distance travelled.

NIMT (North Island Main Trunk)
The route of railway from Auckland to Wellington.

OLE (Overhead Line Equipment)
The network of wires and supporting structures that supplies electricity to electric trains.

PNGL (Palmerston North to Gisborne Line)
The route of railway from Palmerston North to Gisborne.

PTE / PTW (Permit to Enter / Permit to Work)
Authorisations that ensure rail work can be carried out safely and under controlled conditions.

Rail corridor
The land set aside for railway infrastructure.

Rail lubricator
A track mounted device actuated by passing wagons to lubricate rails in order to reduce rail wear.

Rail network
The connected system of railway tracks, stations, signals, and supporting infrastructure used to move people and freight.

Regulator
A track machine used to ensure an even distribution of ballast.

Renewal
The replacement of an asset on a like-for-like basis.

Resleepering
The process of replacing old or damaged sleepers to improve track condition and reliability.

RNIP (Rail Network Investment Programme)
Rail Network Investment Programme.

Rolling stock
All locomotives, railcars, wagons and carriages.

RPO (Rail Protection Officer)
A qualified person responsible for ensuring workers are protected from train movements while working near tracks.

SHW (Safety, Health and Wellbeing)
The KiwiRail department that supports the safety, health, and wellbeing of employees and contractors.

Shunting
To move a locomotive, wagons or carriage onto a different track using a special railway engine designed for this purpose.

Siding
A short section of track connected to the main line, used for parking or loading trains or allowing other trains to pass.

Siding, Terminal or Depot Controller
A person responsible for the co-ordination of Rail Service Vehicle movements in a designated siding, terminal or depot outside the Controlled Network.

Signals
Railway control devices that direct train movements and help maintain safe distances between trains.

Single track
A rail route with one track, allowing traffic to move in only one direction at a time.

Sleeper
The rectangular support, traditionally timber or concrete, that sits beneath the rails and helps keep them in position.

SLW / ALW (Single Line Working / Adjacent Line Working)
Special operating arrangements used when work is taking place on or near one rail line while trains continue to run on the other line.

SPAD (Signal Passed at Danger)
Any signal which has been passed without the correct authority or where the safe-working authority has been exceeded.

SPAD A
A category "A" SPAD is a SPAD where a stop signal indication (and any associated preceding cautionary indications) was displayed correctly, in sufficient time for the train to be stopped safely at the signal.

TAIC
Transport Accident Investigation Commission, Crown investigation agency.

Tamper
A maintenance machine that lifts, aligns and packs ballast beneath railway tracks to keep them level and in the correct position.

TEU (Twenty-Foot Equivalent Unit)
Generally a 20-foot standard container unit to ISO standards.

TMP (Traffic Management Plan)
A plan that sets out how traffic, pedestrians and cyclists will be safely managed during work activities.

TPR / PSR (Temporary Speed Restriction / Permanent Speed Restriction)
Speed limits placed on sections of track. Temporary restrictions are used while issues are being addressed, while permanent restrictions apply long term.

Traction
The electrical power system used to operate electric trains.

Train
A single unit of a locomotive and wagons or carriages.

Train Control
The team that manages train movements across the rail network to ensure services operate safely and efficiently.

Trespasser
A person unlawfully on railway property including the rail corridor (without proper authorisation).

Turnout (also switch or points)
A mechanical installation enabling trains to be guided from one track to another, such as at a junction or where a siding branches off.

UNI / LNI (Upper North Island / Lower North Island)
Regional terms used to describe parts of the North Island rail network.

USI / LSI (Upper South Island / Lower South Island)
Regional terms used to describe parts of the South Island rail network.

Whistle board
A sign beside the railway track that instructs train drivers to sound the train horn when approaching a specific location, such as a level crossing.

Wheel squeal
A high-pitched noise caused by the friction between the metal train wheel and the top or side of the metal rail which can be exacerbated by various factors.

Work Trains
Trains used for maintenance purposes (generally infrastructure maintenance such as ballasting and rail renewals) that are not in revenue service.