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GENERAL DESCRIPTION OF SIGNALS
Aspects of fixed signals are shown by the position of
semaphore arms, color of lights, flashing of lights, position of lights,
or any combination thereof. They may be qualified by number plate, letter
plate, marker, shape and color of semaphore arms, or any combination thereof.
Block and interlocking signals, as far as practicable,
are located to the right of, and adjacent to, or directly over the track
which they govern.
When it is not practicable to locate signals to the right of, or directly
above the track which they govern, two signals may be bracketed and located
on the supporting mast for displaying indications on two tracks, right-hand
signal governing right-hand track and left—hand signal governing
left-hand track.
When a track intervenes to the right between a signal and the track governed,
a stub post with the prescribed marker will be placed to the right of
the signal.
When a track intervenes to the left between a signal and the track governed,
a stub post with the prescribed marker will be placed to the left of the
signal.
Fixed signals of the semaphore type display their indications by arm,
or arms, to the right of the signal mast and in addition, by night, display
lights of the prescribed color as viewed from an approaching train.
Fixed signals of the color light type display their indications by lights
of prescribed color or flashing of such lights as viewed from an approaching
train.
Fixed signals of the position-light type display their indication by lights
arranged in the prescribed position.
Stop signals have no number plates. Stop-and-proceed signals are designated
by number plates.
Block signal numbers indicate their location approximately in miles and
tenths according to mile posts.
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Reduce speed limits are designated
by Advance-warning signs (diagonally upwards), Reduce speed signs
(square with clipped corners) and Resume speed signs (vertical).
The Advance-warning signs are, as far as feasible,
located approximately 3000 feet in advance of the Reduce speed signs,
and the numerals on both signs indicate in miles per hour the maximum
speed permitted from the Reduce speed sign to another Reduce speed
limit, or to a sign indicating a higher speed, or to a Resume speed
sign.
lf speeds authorized by zones or by Reduce speed signs,
are greater than that prescribed in Special Instructions for certain
trains or engines, such trains or engines must not exceed the prescribed
speeds.
Locations where reduced speeds are required, but which
are not indicated by signs, are listed in Special Instructions for
each subdivision.
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UNION PACIFIC BLOCK AND INTERLOCKING
SIGNAL INDICATIONS
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Stop |
Stop
and proceed |
Stop; then proceed at restricted
proceed speed to next home signal. |
Flashing
stop and proceed |
Stop.; then proceed at restricted
stop and speed to next signal keeping close proceed lookout
for track car. |
Permissive |
Proceed at restricted speed to next home signal. |
Approach |
Proceed prepared to stop at next signal. Train
exceeding 30 miles per hour must immediately reduce to that
speed. |
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UNION PACIFIC BLOCK AND INTERLOCKING
SIGNAL INDICATIONS
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Advance |
Proceed on route indicated prepared to pass next
signal at not exceeding 40 miles per hour. |
Clear |
Proceed on main route. |
Restricting |
Proceed on route indicated at restricted speed. |
Diverging approach |
Proceed on diverging route pre-
pared to stop at next signal. |
Dlverging clear |
Proceed on diverging route. |
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UNION PACIFIC INDICATORS
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NAME |
INDICATION |
Operate switch |
Hand operate switch to enter or leave main track. |
Hold |
Communicate with operator or dispatcher before
proceeding. |
Advance |
Proceed on main track to train order signal at
restricted speed, then be governed by train orders or instructions
received. See Rule 87 (A). |
Occupied |
Track occupied. (Governs main track unless otherwise
designated)
See Rule 5l2. |
unoccupied |
Track unoccupied(Governs main track unless otherwise
designated) See Rule 512. |
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