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Republic of Ireland

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Whistle boards comprise a rectangular sign with black and yellow diagonal stripes, below which is mounted a circular white reflector [IE.34]. This style of whistle board was introduced in 1967. The more modern design is reflectorised all over the face of the sign [IE.35].

[IE.34] Whistle Board. [IE.35] Whistle Board.

The standard form of target fitted to level crossing gates in Ireland comprises a white rectangular board with a red diagonal cross [IE.36].

Marker boards comprising a white circle bearing a black letter "V" may be installed on either side of a user-worked level crossing to enable engineering staff to check that sighting distances for crossing users have not been compromised by vegetation growth [IE.37]. These boards were introduced in 2011 on a trial basis following a collision between a freight train and a tractor at a level crossing between Castlerea and Roscommon in 2010.

[IE.36] Gate Target. [IE.37] Vegetation Marker Board.

Most main lines in Ireland have a system of cab signalling called "Continuous Automatic Warning System" (CAWS), first introduced in the Dublin Suburban area in 1984 in conjunction with electrification. CAWS repeats the aspects displayed by lineside colour light signals on a unit in the driver's cab. This "Aspect Display Unit" (ADU) continuously displays the aspect that was shown by the previous main signal. As the train approaches the next main signal ahead, the ADU will show the aspect displayed by that signal. Any change of aspect on the ADU is accompanied by an audible indication. A downgrade to a more restrictive aspect has to be acknowledged by the driver in a similar fashion to the British AWS system. An advantage of the 'continuous' nature of CAWS is that an upgrade in aspect is immediately indicated to the driver when conditions ahead improve. The CAWS system mostly uses coded track circuits to pass the aspect information from the signalling system to the train. On electrified lines, this operates on a different carrier frequency, and drivers of diesel trains must select the appropriate setting when entering or leaving an electrified area. Signs are provided, which show the carrier frequency to be selected ("C1" on non-electrified lines or "C2" on electrified lines) [IE.38]. Another sign marks the end of a CAWS-fitted area [IE.39]. Signs relating to CAWS are distinguished by blue bands across their top and bottom edges.

[IE.38] CAWS Commencement Board (e.g. Carrier 2). [IE.39] CAWS Termination Board.

The coded track circuits in the Dublin Suburban area include additional codes that provide Automatic Train Protection (ATP) functionality for electric multiple unit trains. Where the codes required for CAWS and ATP operation are temporarily unavailable within a defined area, CAWS commencement and termination boards (see [IE.38 & IE.39]) are provided and are accompanied by ATP commencement and termination boards. An ATP commencement board has the letters "ATP" [IE.40], and a similar sign with a diagonal red stripe denotes the termination of ATP [IE.41]. Both signs have blue bands across their top and bottom edges.

[IE.40] ATP Commencement Board. [IE.41] ATP Termination Board.

Where radio coverage begins, a sign is installed to show the correct radio channel to be selected [IE.42]. Another sign is placed at the exit from a radio area [IE.43]. Signs relating to radio are distinguished by yellow bands across their top and bottom edges.

[IE.42] Radio Commencement Board (e.g. Channel 71). Click Here for Photo [IE.43] Radio Termination Board.

The Dublin Suburban lines were electrified on the 1,500 V DC overhead wire system from 1984. Signs are provided to denote the limits of working for electric multiple unit trains [IE.44]. From 1991, on occasions when a substation or switchhouse has to be temporarily put out of use, special coasting boards [IE.45 & IE.46] will be erected at the site concerned. Drivers of EMU trains should avoid drawing power while passing between the coast area boards; otherwise, damage to the overhead line equipment or pantograph could result. Signs relating to electrification are distinguished by orange bands across their top and bottom edges.

[IE.44] Limit of Working for Electric Trains. [IE.45] Coast Area Commencement Board. [IE.46] Coast Area Termination Board.

From c.2000, signs have been provided at the start of single lines worked by the "Electric Train Staff" (ETS) system [IE.47]. A similar sign with a diagonal red stripe [IE.48] marks the end of ETS working. Signs relating to ETS are distinguished by red bands across their top and bottom edges.

[IE.47] ETS Commencement Board. [IE.48] ETS Termination Board.

Stop boards have a white light in the centre [IE.49] or a red spot [IE.50].

"Single Line Working by Remote Pilotman" (SLWRP) is a form of single line working on a double track railway that is established by a pilotman who remains stationed at the signalling control centre. In connection with SLWRP, stop boards are permanently installed at places with crossovers to mark the end of a pilot section for wrong-direction movements. A plate below each stop board displays a two-letter code identifying the location, followed by the letters "Dn" for a Down direction board or "Up" for an Up direction board [IE.51].

[IE.49] Stop Board. [IE.50] Stop Board. [IE.51] Remote Pilotman Working Board (e.g. "PE–DN" for Portlaoise, Down direction).