All train and engine service employees must be equipped with what for passing signals?

For passing signals, train and engine service employees are required to be equipped with a white light. This requirement is crucial because the white light serves as a clear signal to indicate that a train is authorized to proceed past a signal that would typically restrict its movement. In the context of railroad operations, signaling is vital for safety and communication on the tracks; using the correct signaling device helps ensure that both the crew and other personnel on the ground are aware of the train's intentions.

The white light is particularly important because it is universally recognized across various railroad systems and denotes a clear and safe indication for movement. Employees must know this to maintain a high standard of operational safety and comply with LIRR rules and regulations. The other options—red light, yellow flag, and green light—are associated with differing instructions or signals that do not apply to the authorization of passing signals in the same way as a white light does.