What does a GREEN OVER GREEN (IRT) signal signify?

A GREEN OVER GREEN signal in the context of IRT (Interborough Rapid Transit) operations is an indication that the next signal is clear for passage. This means that the train can continue its journey without restriction, as the signal allows for safe and unrestricted movement along the track.

When train operators observe this signal, it reassures them that the route ahead is clear, allowing them to maintain their speed and momentum. This is crucial for efficient train operations, as unnecessary stops can cause delays and impacts downstream traffic.

Understanding the significance of signal indicators is essential for tower operators and train crews in ensuring smooth and safe transit, as they must make real-time decisions based on those signals. In the context of this question, "next signal is clear for passage" directly reflects that operational clarity and efficiency.