What speed must be maintained if cab signals are inoperative while approaching the next home signal?

When cab signals are inoperative, it is critical for the safety of the train and its passengers to reduce speed. The requirement to maintain restricted speed ensures that the train can stop within half the distance of the sighting area, allowing the engineer to respond to any signal indications or obstacles in a safe and timely manner. Restricted speed is a precautionary measure that accounts for the inability to receive continuous signal information, which is crucial for safe train operation.

By adhering to this speed limitation, the train crew is prepared to navigate the situation effectively, ensuring they can halt the train safely in case of unexpected signals or conditions ahead, such as signals showing stop or an obstruction on the track. This approach minimizes the risks associated with potential signal failures and contributes to overall rail safety.

Other speed options do not appropriately address the safety needs in the absence of functioning cab signals. For instance, operating at maximum speed or normal operating speed does not provide the necessary precautions for dealing with emergencies or signal indications when the technology guiding the train is compromised. In contrast, maintaining restricted speed while prepared to stop is a standard response in such scenarios.