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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.

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

Stop 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

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.

UNION PACIFIC INDICATORS

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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