In ABS territory, how long must a train maintain restricted speed due to being delayed within a block?

In Automatic Block Signal (ABS) territory, a train must maintain restricted speed after being delayed within a block until it reaches a signal that displays a proceed indication and the track ahead is clear. This requirement is in place to ensure safety by allowing the train operator to have control over train movements in case of obstacles or signals that need to be respected.

Restricted speed means that a train must not exceed a certain speed, typically allowing time to react if a stop is required. This is particularly important when operating in ABS territory where signals guide train movements. By requiring that the train continues at restricted speed until given a clear and proceed indication from the signal, the protocol ensures that drivers remain vigilant and prepared for any potential dangers or restrictions that may still be present ahead.

The other choices do not correctly encompass the safety measures necessary in this situation. For example, maintaining speed until the next signal is visible could lead to unnecessary risks if the signal is still at stop. Similarly, maintaining speed until the next station is reached does not take into account the operational conditions that could change before reaching that station, and staying at restricted speed until the end of a block might not provide enough clarity about the track condition ahead. Therefore, the expectation is that the train waits for a clear signal