Some GB Railway Jargon

Description of terms and ‘jargon buster’


All industries tend to develop their own shorthand, or jargon, and the railway is no exception. Perhaps matters have accelerated since the world has taken it upon itself to convert any meaningful description into a three-letter acronym and with that in mind I offer the following list in case it is helpful to bemused onlookers of GB rail wondering what on earth people are talking about.

Puzzled man

The List


Automatic Train Operation. ATO can have one of two meanings. In its wider definition it means a mode of operation of a train where movement is controlled automatically, either throughout the whole or part of its journey, or between pairs of stations. Doors may be entirely automatic or, more usually, under part or whole control of a train operator. Automatic trains usually have a member of staff on board who can intervene in case of failure, or drive the train for part of a journey (for example to and from a siding or depot) where it is not worthwhile equipping part of a line with ATO apparatus. Sometimes automatic reversing is a feature, which can be done with the train unmanned.

In its narrower definition ATO is the technical system that manages train starting, stopping and speed on an automatically driven train, and is not a safety-critical system. Safety integrity is provided by a separate safety-critical train protection system (ATP) which will stop a train if the ATO system allows the train to operate outside safety parameters.


Automatic Train Protection: ATP is an automatic system which will as a very minimum intervene to stop a train operating outside defined safety parameters. It can be applied to both manually and automatically driven trains. ATP will generally prevent a train exceeding speed limits or approaching the train in front, or an interlocking where the route is not set, within a certain distance or higher than a safe approach speed. ATP may be applied to automatic railways where normal signals are not used, or on traditional systems. Modern ATP systems provide clear indications in the cab indicating the maximum permitted speed for the line ahead so that drivers can adjust the speed of their train before reaching a section of line where speed is restricted.


Communication Based Train Control.  Signalling systems require knowledge of where the trains are in order to ensure that one train cannot approach another too closely or unsafely, and to ensure routes are locked when occupied by a train. Automatic systems have traditionally identified train locations with trackside apparatus, such as track circuits or axle counters. These identify approximate locations of trains, but with adequate resolution for the task in hand. As railways become more congested it is advantageous to have more precise information about train location, and in addition trackside equipment is a significant source of failures.

CBTC is a system where the train itself identifies its exact location using modern technology such as satellite positioning or distance monitoring via axle rotation (perhaps corrected at intervals with simple trackside location identifiers). Train location is sent continuously by secure radio to a signalling control centre where computers plot positions of all trains in an area and provide train movement authorizations only where trains can safely proceed at particular speeds for the conditions. Movement authorities are then sent continuously by secure radio to the trains to which each authority applies, and this is interpreted by the ATP system on the train (and ATO system, where fitted). By this means trains are able to operate safely based entirely on radio systems and it may not be necessary to have any traditional trackside equipment at all.


Control Period: It wasn't just Stalin's centralist regime in Russia that settled upon 5-year economic plans. On rail privatization, means had to be found to agree Railtrack's operations, maintenance and renewal funding for the next few years which in turn settled track access charges for train operators (and indirectly the government who ultimately provided much of the funding). Five years, though quite arbitrary, was a balance between adequate frequency for rebasing all this and the cost and complexity of undertaking the exercise.

Control periods began in 1994 (CP1) and the latest began in 2009 (CP4). Railway planning is made complex by the various planning horizons being of different frequency and length, and not being related to asset life, which is generally 30 years or more. Reconciling all this is a huge headache. See also ORR, HLOS and SOFA.


Department for Transport: Since 1919 a Ministry of Transport has existed by statute. It has changed its name and form on a number of occasions, and in recent years has been under the control of a Secretary of State (hence 'Department' rather than 'Ministry'). The Department presides over all forms of transport within or touching the UK, and the Secretary of State is sometimes a member of the cabinet.

Current ministers are: Lord Andrew Adonis (Secretary of State); Sadiq Khan (Minister of State, attends cabinet and is transport lead in House of Commons); Paul Clarke and Chris Mole (Parliamentary Under Secretaries of State). Lord Adonis is a full cabinet minister.


Because railways across Europe developed largely independently of each other, each has developed its own operating practices and principles. Currently there are 20 different systems in use. With the move to European interoperability (the facility for operators to operate over each others networks and to procure similar equipment) there has arisen a need to rethink these principles. It is not that cross border operations cannot be achieved under the existing processes, for they can, and they have been for perhaps a century or more. However, it requires a great deal of additional training and the complexity of modern systems means duplication of a great deal of equipment in the cab. Modern European locomotives might have to be fitted with typically three or four different systems (some are fitted with up to seven), which is expensive and inefficient.

The favoured EC solution is the European Railway Traffic Management System, ERTMS, which is a long term aspiration to allow complete interoperability across Europe using modern technology as well as reducing operating costs. What, then, is ERTMS? The answer is that ERTMS itself isn’t a system in its own right, it is more a protocol. The technical contribution comprises two different systems that work together. The first is the European Train Control System (ETCS) which is a cab-based automatic train protection system (ATP) which will provide the driver with information about the maximum speed allowed for the train and intervene if this is exceeded. This will ensure trains are always physically separated by a distance within which it can be brought to a stand. The second system is called GSM-R (which stands for Global System for Mobile communications – Railways) which is a purpose designed system to facilitate secure voice and data communications between train drivers and signallers or data centres.

ERTMS is amenable to phased introduction and has been configured to be applied at one of three different ‘levels’, Level 3 being the aspirational Europe-wide fully-configured radio controlled system.

Level 1 is the most basic application and is overlaid on existing systems that use fixed trackside signals. A device called a ‘balise’ (sometimes called a eurobalise) is fixed to the track near existing signals and repeats in the cab the information about whether or not a train can proceed (a movement authority). Trains need to be fitted with ETCS and on-board technology can calculate from information picked up from the balises the maximum speed at which a train ought to be moving at any point and intervene if necessary. On its own this introduces a large degree of interoperability across borders and projects. It may be implemented in two forms. System A simply introduces balises in conjunction with existing fixed signals. System B introduces additional balises to update more frequently and increase capacity, but it introduces more equipment and complexity (and cost) with commensurate disadvantages.

Level 2 introduces GSM-R, which will provide the necessary movement authorities via continuous data links. The balises are retained but are used to confirm exact location or transmit fixed messages, such as speed restrictions. The continuous data link means that trains are no longer reliant on fixed lineside signals (which can be eliminated to reduce maintenance) and can respond immediately to changes in the condition of the line ahead, increasing line capacity. Level 2 can be implemented in three ways. System C retains lineside signals and overlays radio communications providing continuous updates (this may be essential during transition). System D removes (or at least minimizes) lineside signals removing capacity constraints; this requires entirely new operational rules. System E is a low density application for very lightly used lines and has the advantage of removing most trackside infrastructure.

Level 3 (which is still conceptual) eliminates the traditional railway fixed-block track circuit and allows moving block technology to be introduced which continuously spaces trains apart depending on line speed and gradient, allowing a further step change in improving capacity. This is achieved by each train continuously reporting its own position by radio, eliminating any need for track circuits, axle counters or other fixed means.

ERTMS has been long in the making and deployment is also a slow process. Across Europe there are currently 10,000 route miles of track equipped (217 in the UK), and 3000 vehicles (17 in the UK). Perhaps of some interest is that there is a similar amount of track equipped outside Europe, with a further 1700 vehicles, and this includes countries as far away as India and Mexico. There is every chance that ERTMS will become a global standard in the near future.

ERTMS is a major industrial project developed by six European rail industry leaders – Alstom Transport, Ansaldo STS, Bombardier Transportation, Invensys Rail Group, Siemens Mobility and Thales – in close cooperation with the European Union, railway stakeholders and the GSM-R industry.


High Level Output Statement. A periodic statement issued by the Department for Transport specifying in broad terms the outputs desired from the railway industry during the following control period. The HLOS is supposed to indicate the approximate network size, service volume and quality of services required in order to direct the tactical thinking of the various industry players and allow them to determine the cost of such provision.

The main player in this iterative process is the independent office of rail regulation which has specific duties to ensure that Network Rail is adequately funded to meet its long term obligations, mainly through the track access charge regime. The HLOS has to be deliverable within the funds available, which presents some challenges.

HLOS aspirations also impact on future improvement projects and the delivery and deployment of new rolling stock. This is a new process and has only operated once, so far, but work is beginning to give thought to the next round which has to be complete in good time for the 2014-2019 control period.


Integrated Transport authority: Under the Local Transport Act 2008 the existing Passenger Transport Authorities in the 'conurbations' are renamed Integrated Transport Authorities. Although more powers are given to these authorities for use in certain circumstances, they are essentially the same bodies and there is no attempt to introduce compulsory bus regulation such as that existing in London. Day to day operations are, as before, undertaken by the statutory Passenger Transport Executives. ITAs therefore exist in the six Metropolitan areas of Greater Manchester, Merseyside, South Yorkshire, Tyne & Wear, West Midlands, West Yorkshire. The Act makes provision for other local authorities (County or Unitary Councils) to get together for transport planning purposes and apply for ITA status, but the legislation has not been in force long enough for this to have been done yet. The words Integrated Transport are not well defined and over many years have been viewed as hard to deliver (perhaps partly because the definition is poor and lacks consensus). Public clamour has found the words being increasingly used in support of government policy, or perhaps instead of it.


Integrated Transport Smartcard Organization: The body set up at the instigation of government to promote a common standard for cross modal smartcard ticketing across the UK. Functionally the ITSO-compliant ticketing should be at least as fully-featured as London's Oyster scheme, but technically much more versatile and extendable (Oyster is technically quite old and difficult to extend outside London. Oyster is likely to require upgrading to ITSO standards at some point).


Office of Rail Regulation: The independent body responsible for regulating the rail industry and in particular monopoly supplier Network Rail. Follow this link to longer explanation.


Public-Private Partnership: With transport funding from the government annualized and competing with other demands for public expenditure it was getting progressively more difficult to guarantee funding for London Underground projects. Meanwhile asset condition was deteriorating and affecting service delivery against a background where more people were being carried. There was also a suspicion that London Underground was unable to manage large projects efficiently, a view partly fuelled by late and overspent delivery of the Jubilee Line extension.

There had already been a number of initiatives funded via the Private Finance regime and the post 1997 labour government determined that the principle could be much expanded under the new PPP name. The concept was simple enough. The assets would be transferred to the private sector who would upgrade them having borrowed the money to invest. The Underground would identify what the outputs were that were important, and the private companies would lease back the trains, track and other assets on a daily basis meeting the rising level of outputs that had been specified. Incentives were put in place to reward overperformance and discourage underperformance. The maintenance and project staff would all transfer to the private sector while operations would remain in the public sector.

The mechanism by which all this would work is subtle. The benefits were that the private sector could borrow as much money as it needed to upgrade the network and begin to rebuild it much faster than LUL would have been able to. New techniques and the private sector magic touch would improve quality and speed of delivery. The private sector would carry all the project risk. LUL would pay pretty much constant leasing charges, making its cash far easier to manage. The investment funds would not appear as a government debt. The downside was that private money was more expensive than public money and in addition the private sector would need to make profits. Additional costs would arise simply to manage the contracts, and there might be some duplication. It would be harder to make changes once contracts had been agreed. There would be friction with existing PFI contracts. There would be high reorganization costs. The government thought that the benefits would outweigh the disbenefits.

The reality was that the PPP mechanism was really all about getting modernization work done sooner than it might have been by borrowing future money on the basis an ongoing business would eventually pay it all back. Two companies were formed. Metronet (Balfour Beatty, Thames Water, SeeBoard and Bombardier and WS Atkins) and Tubelines (Bechtel, Amey and Jarvis). The latter took over the Northern, Piccadilly and Jubilee Lines and Metronet had the rest. The 30 year contracts started in 2003. Subsequently Jarvis pulled out and Amey was taken over by Spanish firm Ferrovial, who own the majority of Tubelines shares.

This hasn't really worked. Debts are now counted as public debt. It is in practice very difficult to do too many projects at once because of the Underground environment, difficulties in gaining access and public reaction to excessive closures. Costs were higher than anticipated for lots of reasons. It hasn't been a 'partnership' and because so many existing staff transferred and LUL found it hard to 'let go' the amount of innovation was limited. Metronet failed in 2007 was subsequently taken over by London Underground, though the PPP contract is still in force. Tubelines appeared likely to go the same way and was recently purchased by London Underground. Although the contracts are still alive as a technicality, the reality is that engineering has all been brought back 'in house' and further pain will be endured reorganizing the various functions.


Passenger Transport Authority. Established under Transport Act 1968 to provide control of transport policy and planning in six areas of Britain, known as 'the conurbations'. See also ITA.


Passenger Transport Executive. Established under Transport Act 1968 to provide day to day management of transport services in those areas under the control of a PTA. Local authority bus services in those areas were transferred to the PTE. Local rail services generally remained in the ownership of British Rail but branding, funding and service specification was set by the PTE and ticketing was often integrated with wider PTE ticketing practice. Some PTEs have come to operate their own tram and Metro services as well. PTEs exist in the six Metropolitan areas of Greater Manchester (GMPTE), Merseyside (Merseytravel), South Yorkshire, Tyne & Wear (Nexus), West Midlands (Centro), West Yorkshire (Metro). Following bus deregulation from 1986, the PTEs were required to divest themselves of direct bus operations, setting up arms-length companies supervised by the PTAs; these were subsequently sold in the early nineties. Tram operations were usually procured via design-build-operate entities and directly-operated Newcastle Metro (part of Nexus) is currently being put out to tender. Under the 2008 Local Transport Act PTEs are again allowed to run their own vehicles but it is too soon to say how this policy will evolve.


Railway and Other Guided Transport (Safety) Regulations. ROGS implements within the UK the requirements of the Safety Directive issued in 2004 on behalf of the European Union which is intended to harmonize the safety requirements placed on guided transport systems, primarily railways. The regulations came into force in 2006 and replace earlier regulations which required railways to hold a 'safety case'.

The new regulations apply to anyone operating main line railway infrastructure (the infrastructure owner) and to people operating the infrastructure and its stations or operating vehicles over that infrastructure or serving its stations. Collectively these may be called Transport Operators.

ROGS requires Transport Operators to: develop a safety management system, operate safety verification procedures, have safety certificates and authorizations, undertake risk assessments, produce annual safety reports, work together to make sure the system as a whole is safely run, and have special procedures in place when staff carry out safety critical work. The new system expects people to document systems and processes proportionately to size and risk, unlike 'one size fits all' arrangements that applied previously.

The safety certificate is issued by the Office of Rail Regulation in response to an application which must contain all the necessary information required to show the nature of the railway system and how the various safety issues will be managed. This needs to be supplied at a higher level than the former safety case. For main line railways the application must include separate details about how European safety obligations are to be met, in addition to obligations applying only to UK (for non main line systems only the latter is required).


Rolling Stock Leasing Company - These are the bodies set up at the time of rail privatization to take ownership of the existing rail fleet and to lead the purchase of new passenger rolling stock and locomotives for the industry. Three companies were set up, in each case being given for responsibility for ownership of about a third of the ex BR fleet. Stock was distributed in such a way that there was 9in theory) competition for the various types of train each of the train operators leased, intended to reduce the risk of monopoly supply.

There were originally three leasing companies, Angel Trains, Eversholt and Porterbrook. Since these were more financing than engineering companies, it is perhaps not surprising to find them soon taken over by Banks - Angel going to Royal Bank of Scotland, Eversholt to HSBC and Porterbrook to Abbey National (later Santander). Porterbrook was recently sold to a consortium of Deutchbank, Lloyds and Antin Partners (BNP Parisbas Bank). Angel was sold at about the same time to Babcock & Brown European Infrastructure Fund, AMP Capital and Deutsche Bank. Angel had developed an international business and at time of sale the international side of the business was renamed Alpha Trains.


Statement of Funds Available. A periodic statement issued by the DfT at or about the same time as the HLOS. This is a statement of the expected revenues of the various public-sector managed rail businesses coupled with additional funds that the DfT is prepared to pledge to the industry for political reasons. The SOFA is intended to pay for the service levels demanded by the HLOS, and getting the two to balance is a lengthy and iterative process. The process will leave a number of challenges to be met, particularly in the case of Network Rail funding, which is inclined to be lower than requested. It is important to get this process right. The office of rail regulation determines the charges Network Rail makes to operators for access to the Network, and higher than expected charges have to met by government.


Trans-European Network:  Within the European Union there is an aspiration for the whole of the European rail network to become a single system developing to meet the needs of the community as a whole. This requires huge changes to operating practices so that trains from one country can operate safely and conveniently along the metals of another. The process has started with the definition of a Trans-European Network (TEN). In fact TEN is divided into a high speed network (only applicable in UK to the St Pancras - Channel Tunnel HS1 route) and the conventional network, which is a significant proportion of the UK network and includes all inter city and long distance routes, but not what might be called inner or outer suburban services.

In order to ensure harmonization of methods the EU is issuing various Technical Standards for Interoperability, introduced in stages beginning with those for the High Speed network, and followed up by TSIs for freight and then passenger services. A number of these have already been issued and UK legislation has given them legal status in the UK and, where necessary, altered or removed conflicting requirements. In the UK a new species of approvals body has been required (called Notified Bodies) who will certify that new equipment and rolling stock brought into use complies with the new regulations.


Transport for London; TfL is a public authority created by the Greater London Authority Act 1999 and is classed as a local authority. TfL is an executive body intended to deliver on behalf of the Mayor and Assembly for London the Mayor's transport strategy. TfL includes responsibility for surface and waterborne transport modes, including important London streets and the licensing of cabs. Through a number of subsidiary bodies TfL procures nearly all London bus and river services and London Overground rail services. TfL has direct responsibility for operation of London Underground Ltd and Docklands Light Rail Ltd services, and has responsibility for delivering the Crossrail project in conjunction with Network Rail.

TfL is chaired by the Mayor with day to day responsibility for transport operations and delivery of the strategy in the hands of London's Transport Commissioner, Peter Hendy.


Train Protection Warning System. The pre-war Automatic Warning System could not cope well with modern signalling. Following a number of accidents where AWS inadequacies had been implicated a better system was considered necessary. The objective was to get away from the binary outputs of the AWS system and introduce one where drivers actions were checked against system expectations. TPWS works by identifying the aspects of associated signals and measuring train speed on their approach. It is anticipated that drivers will slow down appropriately on approach to signals showing various aspects (the more restrictive the aspect the lower the speed) and TPWS checks that at a suitable point the train is not exceeding a reference speed for that signal aspect. By this means the system checks that a train has responded suitably to the conditions and triggers an emergency stop if it exceeds the reference speed.

TPWS is also applied on approach to terminal platforms and where there are severe speed restrictions. Because it operates by measuring speeds between closely located beacons it is only fully operative for speeds below 70 mph, though it will severely slow down faster trains not properly under control approaching signals, thereby vastly reducing the energy in the event of a collision or derailment. It is regarded as an interim system prior to introducing ERTMS.


Transport and Works Act: Railways historically have been built with the authority of the UK Parliament by means of a private Act. All interested parties have an opportunity to influence the nature and extent of the powers as the legislation passes through its various bill stages and the resulting Act confers compulsory purchase powers, an authority to operate the enterprise as a railway and imposes various constraints upon the operator.

This process was considered rather cumbersome and unnecessarily tied up parliamentary time. In 1992 a Transport and Works Act was passed which allowed the Minister to authorize railway construction and operation if he were satisfied it was in the public interest. To establish whether this was so, transport operators must submit a detailed application that conforms to certain rules, and a public enquiry is held during which interested parties can participate. Generally parties are mainly concerned about protecting property and property values, or that disturbance is kept to an absolute minimum. The inspector then makes his own recommendations and once everyone is as happy as is reasonable the document goes to the Minister who will then (usually) make the necessary Order. The Order takes the form of a statutory instrument (covering the same ground as previously covered by private Act) and once made provides all the necessary statutory authority.

Exceptionally a private Act is still required, usually for very large schemes or schemes involving private interests that require a so-called hybrid bill. Crossrail would be such an example. Private Acts are still necessary where parliamentary authority is required other than construction and operational powers.


Technical Standard for Interoperability: TSIs are drafted by the European Association for Railway Interoperability (AEIF), in consultation with interested parties throughout the industry. The AEIF is a joint body of the International Union of Railways (UIC) and the European Railway Industry Association (UNIFE). The TSI approval process is co-ordinated by an AEIF committee with representatives from all EU nations including the UK. In the UK the process is co-ordinated through the Rail Safety and Standards Board and the DfT. See also 'TEN' (above).

As it will be extremely difficult to apply some TSIs to only part of the national network (for example those that will influence the railway rulebook) it is likely that the whole of the mainline network will eventually be susceptible to the majority of TSIs. Local railway administrations may impose more stringent requirements than TSIs require, but these must be notified to and are challengeable by the EU where it appears restrictions may impose barriers to freedom of train access or trade.