******** Signs & Symbols Used In Railway Tracks *******
1 Speed Limit Number on triangular yellow board : speed limit in km/h. 'KMPH' or 'KM/H' may optionally appear below the number. Black text.Sometimes the board has additional text, for instance 'RAJDHANI ONLY' may appear at the bottom, indicating that the speed is restricted for the Rajdhani service on this stretch.
2 Speed Limit - Rajdhani/Shatabdi Number on blue board: indicates a special speed limit (in km/h) for Rajdhani and Shatabdi trains. Text is in white. (But see above -- sometimes the...
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normal speed limit board is used with additional annotations for these trains.)
3 Termination Indicator T (painted on a yellow circular board) : Termination of speed limit
4 Termination Indicators T/P, T/G, or T/BOXN (painted on a yellow circular board) : Termination of speed zone for, respectively, passenger trains, goods trains, and goods trains with BOXN wagon rakes. In urban areas similar signs such as T/EMU, T/EMU-9, etc., may be seen (termination of speed limit for EMU rakes, EMU rakes with 9 coaches, respectively). Other termination indicators seen include T/PG (for both passenger and goods trains, seen on ECoR), T/P24 (for 24-coach or longer passenger trains), and T/L (for local, i.e., suburban trains, usually EMU or DMU trains). The Hyderabad area MMTS system uses a T/M sign for its trains. T/R is sometimes seen for railbuses. Occasionally, the sign T by itself is shown to indicate a termination of speed limit for all trains. A T/Raj sign was in use for Rajdhani trains when they were first introduced but is no longer used now. WR used T/Raj indicators for the 8-coach Bombay - New Delhi Rajdhani, and its EMUs used the same sign as a termination indicator.
5 Whistle Indicators 'W', or 'W/L' on a square yellow board. The 'W' is a general whistle indicator while the 'W/L' stands for Whistle for Level Crossing. The latter is also seen in Hindi with the characters 'see/pha' == 'seetee bajao - phatak'). Usually provided on approach to unmanned level crossings (and for manned level crossings without a clear view) about 250m away from the level crossing. Similarly, a 'W/B' sign is seen (less often) on approach to a bridge.
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