SIGNALS A GENERAL PROVISIONS

3.01 GENERAL USE OF SIGNALS.—
The signals prescribed in these rules shall be used for controlling the movement of train in all cases in which exceptions are not allowed by approved special instructions.
3.02 KINDS OF SIGNALS.—
The signals to be used for controlling the movement of trains shall be—
(a) fixed signals,
(b) hand signals,
(c) detonating signals and
(d) flare signals.
3.03 USE OF NIGHT SIGNALS BY DAY.—
The signals prescribed in these rules for use by night shall also be used by day in tunnels and in thick, foggy or tempestuous weather impairing visibility.
3.04 PLACING OF SIGNALS AND SIGNAL ARMS; PAINTING OF SIGNAL ARMS.—
(1) Fixed signals shall be clearly visible to the Loco Pilots of trains approaching them and shall be placed immediately to the left of or above the line to which they refer, unless otherwise authorised by special instructions.
(2) In the case of semaphore signals, signal arms shall be placed on left hand side of the post as seen by the Loco Pilot of any approaching train to which they refer.
(3) (a) Except as provided for in clauses (b) and (c), signal arms shall be painted with the same colour as the light exhibited in the ‘on’ position with a white bar on the side facing trains to which they refer and white with a black bar on the other side. Such bars shall be parallel with the end of the arms.
(b) In the case of a yellow arm, a black bar shall take the place of the white bar on the side facing trains.
(c) Calling-on arms shall be painted white with a red bar on the side facing trains to which they refer and white with a black bar on the other side.
B. DESCRIPTION OF FIXED SIGNALS
3.05 USE OF FIXED SIGNALS.—
(1) Except under approved special instructions, all railways shall be equipped with fixed signals as prescribed in these rules.
(2) The aspects of a semaphore signal shall be displayed by the position of the arm by day and by a light or lights by night.
Note: - In the illustrations given in this Chapter, which are not drawn to scale, the day aspect of the semaphore signal is shown by the position of the arm and the night aspect is shown by the light or lights to the right of the signal concerned.
(3) The aspects of a colour light and position light signal both by day and by night shall be the same and shall be displayed by fixed light or lights.
(4) The arm of a semaphore signal shall work in –
(a) the lower quadrant in two – aspect signalling and
(b) the upper quadrant in manually operated multiple-aspect signalling.
(5) The ‘off’ position of a semaphore signal shall be displayed by day by the inclined position of the arm from 450 to 600 below the horizontal in case of two-aspect lower quadrant signals and 450 or 900 above the horizontal in case of multiple-aspect upper quadrant signals.
3.06 DESCRIPTION OF WARNER SIGNALS AND THEIR INDICATIONS.—
(1) A semaphore Warner signal has a fish-tailed arm.
(2) A Warner signal is intended to warn a Loco Pilot—
(a) of the condition of the block section ahead, or
(b) that he is approaching a Stop signal.
(3) A Warner signal may be placed either—
(a) on a post by itself with a fixed green light 1.5 to 2 metres above it by night, or
(b) on the same post below the first Stop signal or the last Stop signal.
(4) When placed in accordance with clause (b) of sub-rule (3), the variable light of the Stop signal shall take the place of the fixed green light of the Warner signal and the mechanical arrangement shall be such that the Warner signal cannot be taken ‘off’ while the Stop signal above it is ‘on’.
(5) The aspects and indications of a semaphore Warner signal are shown below: -
(a) Semaphore Warner signal in Two-Aspect Signalling Territory – on a post by itself

(6) The aspects and indications of a colour light Warner signal are shown below: -
(a) Colour Light Warner signal in Two-Aspect Signalling Territory on a post by itself

(b) Colour Light Warner Signal in Two – Aspect Signalling Territory-below a Stop signal

(7) A Warner signal with a fixed green light above it by night, on a post by itself, shall be located at an adequate distance in rear of the Stop signal, the aspect of which it pre-warns:
Provided that when such a Warner signal applies to a gate Stop signal it shall not display the ‘Proceed’ aspect unless there is adequate distance between the gate Stop signal and the first Stop signal of the station ahead. The adequate distance in such a case shall never be less than 1200 metres.
(8) Where special circumstances justify the use of an unworked Warner, it shall be secured in the ‘on’ position and not be coupled or duplicated for directing purposes.
3.07 DESCRIPTION OF DISTANT SIGNALS AND THEIR INDICATIONS.—
(1) A semaphore Distant signal has a fish-tailed arm.
(2) The aspects and indications of a semaphore Distant signal working in the lower quadrant are shown below: -

Note: - This signal shall be provided only in Modified Lower Quadrant signalling.
(3)The aspects and indications of a semaphore Distant signal working in the upper quadrant are shown below: -

Note: - The distance between the two yellow lights shall be 1.5 metres when this signal displays ‘Attention’ aspect at night.
(4) The aspects and indications of a colour light Distant Signal are shown below: - Colour light Distant signal in Multiple-Aspect Signallin Territory

(5) A Distant signal shall be located at an adequate distance in rear of the Stop signal, the aspect of which it pre-warns.
(6) Where necessary more than one Distant Signal may be provided. In such a case, the outermost signal, to be located at an adequate distance from the first Stop signal, shall be called the Distant Signal and the other called the Inner Distant signal, with the Distant signal capable of displaying ‘Attention’ or ‘Proceed’ aspect only.
(5) A Distant signal shall be located at an adequate distance in rear of the Stop signal, the aspect of which it pre-warns.
(6) Where necessary more than one Distant Signal may be provided. In such a case, the outermost signal, to be located at an adequate distance from the first Stop signal, shall be called the Distant Signal and the other called the Inner Distant signal, with the Distant signal capable of displaying ‘Attention’ or ‘Proceed’ aspect only.
(7) Under approved special instructions, a colour light Distant Signal may be combined with the last Stop signal of a station in rear or with a Stop signal protecting a level-crossing.
When a colour light Distant signal is combined with the last Stop signal of a station in rear or with a Stop signal protecting a level–crossing, arrangements shall be such that the signal shall not display a less restrictive aspect than the ‘Stop’ aspect till Line Clear had been obtained from the station ahead in the former case and until the level-crossing gates have been closed and locked for the passage of trains in the latter case.
3.08 DESCRIPTION OF STOP SIGNALS AND THEIR INDICATIONS.—
(1) A semaphore Stop signal has a square ended arm.
(2) The aspects and indications of a semaphore Stop signal, working in the lower quadrant are shown below: - Semaphore Stop signal in Two-Aspect Signalling Territory.

(4) The aspects and indications of a colour light Stop signal are shown below: -
(a) Colour light Stop signal in Two-Aspect Signalling Territory

(b) Colour light Stop signal in Multiple Three-Aspect Signalling Territory

(c) Colour light Stop signal in Multiple Four—Aspect Signalling Territory

3.09 KINDS OF FIXED STOP SIGNALS FOR APPROACHING TRAINS.—
(1) The Stop signals which control the movement of trains approaching a station are of three kinds, namely-Outer, Home and routing signals.
(2) The Outer Signal, where provided, is the first Stop Signal of a station and is located at an adequate distance outside the point up to which the line may be obstructed, after Line Clear has been granted to, or obtained by the station in rear.
(3) The Home signal is the first Stop signal of a station at which an Outer signal is not provided and the second Stop signal of a station at which an Outer signal is provided. It shall be located outside all connections on the line to which it refers.
(4) The Routing signal is a signal used to indicate to a Loco Pilot which of two or more diverging routes is set for him, when the Home signal is, in consequence of its position, inconvenient for this purpose.
3.10 KINDS OF FIXED STOP SIGNALS FOR DEPARTING TRAINS.—
(1) The Stop signals which control the movement of trains leaving a station are of two kinds, namely-Starter and Advanced Starter.
(2) When a train leaving a station is guided by only one starting signal, it is the last Stop signal of the station and is called the Starter.
(3) When a train leaving a station is guided by more than one Starter Signal, the outermost starting signal is the last Stop Signal of the station and is called the Advanced Starter.
(4) The Starter, where only one such signal is provided, or the Advanced Starter, shall be fixed at the limit, beyond which no train may pass, unless the Loco Pilot is given the authority to proceed required under the system of working and shall be placed outside all connections of the line, to which it refers except where otherwise allowed by approved special instructions. Shunting operations beyond this limit shall be carried out only in accordance with special instructions.
(5) Where an Advanced Starter is provided, the Starter referring to any line shall be placed so as to protect the first facing points or fouling mark of the connections, to another running line.
3.11 INTERMEDIATE BLOCK STOP SIGNAL.—
Intermediate Block Stop signal is the Home signal provided at an Intermediate Block Post.
3.12 KINDS OF FIXED STOP SIGNALS IN AUTOMATIC BLOCK TERRITORIES.—
(1) Stop signals in Automatic Block territory shall be colour light signals and may be of the following kinds-
(a) an Automatic Stop signal which is not dependent upon manual operation but is controlled automatically by the passage of a train into, through and out of the automatic block signalling sections;
(b) a Semi-Automatic Stop signal which is capable of being operated either as an Automatic Stop signal or as a Manual Stop signal,as required;
(i) when a Semi-Automatic Stop signal works as an Automatic Stop signal, it assumes ‘on’ and ‘off’ aspects automatically according to the condition of the automatic block signalling sections ahead;
(ii) when a Semi-Automatic Stop signal works as a Manual Stop signal, it assumes ‘on’ aspect automatically on the occupation of the automatic block signalling section ahead, but assumes ‘off’ aspect when operated manually, provided the relevant automatic block signalling sections ahead are clear;
(iii) when a Semi-Automatic Stop signal works as an Automatic Stop signal, the ‘A’ marker provided under the signal is illuminated. When the ‘A’ marker is extinguished, the signal shall be deemed to work as a Manual Stop signal;
(b) a Modified Semi-Automatic Stop signal by converting one of the Automatic stop signal in mid-section under special instructions; when the ‘A’ marker is illuminated the signal works as Automatic stop signal, and when the ‘A’ marker is extinguished it works as modified Semi-Automatic stop signal and assumes ‘off’ aspect automatically or is taken ‘off’ manually as required; and
(c) A Manual Stop signal operated manually and which cannot work as an Automatic or a Semi-Automatic Stop signal.
(2) Colour light signals in automatic Block territory shall be threeaspect or four-aspect.
3.13 CALLING-ON SIGNALS.—
(1) A Calling-on signal is a subsidiary signal, which has no independent aspect in the ‘on’ position and shall be-
(a) a short square ended semaphore arm, or (b) a miniature colour light provided with a ‘C’ marker.
(2) A Calling-on signal, where provided, shall be fixed below a Sto signal governing the approach of a train. Under approved special instructions, a calling-on signal may be provided below any other Stop signal except the last Stop signal.
(3) A Calling-on signal, when taken ‘off’ calls on the Loco Pilot of a train to draw ahead with caution, after the train has been brought to a stop, even though the Stop signal above it is at ‘on’ and indicates to the Loco Pilot that he should be prepared to stop short of any obstruction.
(4) A Calling-on signal shall show no light in the ‘on’ position.
(5) The aspects and indications of a semaphore Calling-on signal are shown below: -
(a) Miniature Semaphore Arm type Calling-on signal in TwoAspect Signalling Territory.