AUTOMATIC BLOCK SIGNAL SYSTEM RULES
505. Block signals, cab signals, or both govern the use of the blocks but do not supersede the superiority of trains unless Rule 251 or Rule 261 is in effect. They do not dispense with the use or observance of other signals whenever and wherever required.
506. When an interlocking is in use in ABS territory, interlocking rules govern movements through the interlocking.
507. When signals in ABS territory are withdrawn from service trains will be governed by instructions from the train dispatcher.
508. A station protection signal affords protection against all trains in the direction in which the signal applies, and movements may be made in either direction in the block at restricted speed. When a station protection signal does not form part of an ABS, protection extends only to the “Block End” sign, and Rules 512 and 513 must be observe.
Where approach signals are not provided, approach signs will be placed one mile from station protection signals.
509. When a train or engine is stopped by a signal indicating “STOP” and no conflicting movement is evident:
(a) A member of the crew must immediately communicate with the train dispatcher, stating his name, occupation, location and train or engine number.
(b) On information from the train dispatcher that there is no conflicting train movement, the train or engine may proceed at restricted speed to the next signal.
(c) If unable to secure the information that there is no conflicting train movement, it may proceed only under flag protection (as prescribed for OUTSIDE ABS TERRITORY) to the next signal displaying a less restrictive indication than Stop or Stop and Proceed.
(d) Instruction received from train dispatcher must be in writing and repeated before being acted on, and train dispatcher must make the proper record immediately.
510. A train or engine which is to enter a siding or yard track at a point where the switch to be used is not more than 500 feet beyond a Stop and Proceed signal may pass such signal at restricted speed without stopping provided the switch is lined for the track to be used and the track between the signal and the switch is seen to be clear.
512. Where block indicators are provided, the indicator must be observed immediately before a main track switch is opened. When indication shows “track occupied” the switch must not be opened unless the movement is protected as prescribed by Rule 99 for OUTSIDE ABS TERRITORY, except at meeting points on single track when the train to be met has cleared the switch and is occupying the block. The indication “track unoccupied” does not authorize a train or engine movement, and does not relieve employees from protecting their train or engine as prescribed by the rules.
513. Where block indicators are not provided or when declared out of service, a train or engine which is to foul or enter a main track from a crossover, siding, or other track, must wait three minutes after the main track switch has been opened before moving foul, except at meeting points on single track when the train to be met has cleared the switch and is occupying the block. This will not relieve employees from protecting their train or engine as prescribed by the rules.
514. A train or engine entering a block between signals must be protected as required by the rules and must proceed at restricted speed to the next signal unless the track is seen to be clear to the next signal and such indicates proceed.
EXCEPTION: This rule does not apply in CTC when entering a block in CTC where an electrically-locked hand operated switch is provided.
515. When a train or engine has passed a signal permitting it to proceed at other than restricted speed and is delayed in the block, it must proceed at restricted speed to the next signal unless the track is seen to be clear to the next signal and such indicates proceed.
516. A train or engine having passed beyond the limits of a block must not back into the block except under protection.
517. If any part of a train or engine overruns a signal indicating STOP, front of train or engine must be protected immediately under Rule 99 for OUTSIDE ABS TERRITORY, and member of crew must immediately communicate with train dispatcher and be governed by his instructions.
518, To avoid holding main track signals at stop, cars or engines must not be allowed to stand between the standing point and a main track switch.