Page 289 - IRSEM_Main Book

(b) A repeating signal shall be of a square ended Semaphore arm.

(i) The arm of a semaphore repeating signal shall be square ended. The front
of the arm shall be yellow with a black bar. The back of the arm shall be
white with a black bar. The bars shall be parallel to the end of the arm.

(ii) By day, the arm shall be horizontal in the 'ON' position and 45° to 60°
below the horizontal in the 'OFF' position. By night the signal shall exhibit a
yellow light in the 'ON' position and a green Light in the 'OFF' position.

12.5.11 Co-acting Signals: Co-acting signals are duplicate signals fixed below Stop
Signals and are provided where, in consequence of the height of the signal
post or of there being an over-bridge or other obstacle, the main arm or light
is not in view of the Driver during the whole time that he is approaching it.

Multiple Aspect Signalling

12.5.12 Distant Signals

(a) Electric Lighting of Distant Signal: Distant Signals shall be electrically
lit on all the Trunk routes and important main lines.
(b) Location: On both double and single line sections, the Distant Signal
shall be placed at an adequate distance in rear of the First Stop Signal,
the adequate distance being not less than 1 kilometre.

(c) Semaphore arm: The Semaphore arm of a Distant Signal shall be fish-
tailed. The front of the arm shall be yellow with a fish-tailed black bar. The
back of the arm shall be white with a fish-tailed black bar.

(d) Day and night indications

(i) By day, the arm of a Distant Signal shall be horizontal in the 'ON'
position displaying the 'Caution' aspect. It shall be 40° to 45° above
the horizontal in the 'OFF' position displaying 'Attention' aspect. It shall
be 85° to 90° above the horizontal in the 'OFF' position displaying the
'Proceed' aspect.

(ii) By night, the signal shall display one yellow light for the 'Caution'
aspect, two yellow lights in a vertical line 1.5 meters apart for the
'Attention' aspect and one green light for the 'Proceed' aspect.

12.5.13 Stop Signals

(a) The Semaphore arm of a Stop Signal shall be square ended. The front of
the arm shall be red with a white bar. The back of the arm shall be white
with a black band. The bars shall be parallel to the end of the arm.

(b) Day and night indications

(i) By day, the arm of a Stop Signal shall be horizontal in the 'ON' position
displaying the 'STOP' aspect. It shall be 40° to 45° above the horizontal in
the 'OFF' position displaying the 'Caution' aspect. It shall be 85° to 90°
above the horizontal in the 'OFF' position displaying the 'Proceed' aspect.

Chapter 12: Installation, Testing & Maintenance of Mechanical Signalling Equipment Page 243 of 535