What is the first action to take when ascertaining the exact location of a train?

The most appropriate first action when ascertaining the exact location of a train is to ascertain the exact location of the train and inform the Rail Control Center (RCC). This step is crucial because knowing the precise position of the train allows for proper coordination and response to the situation at hand.

Understanding the train's exact location is foundational for ensuring safety and efficient management of train operations. Once the train's position is identified, the RCC can take necessary actions, such as dispatching assistance or making route adjustments to avoid potential conflicts or delays with other trains.

While informing passengers and communicating with neighboring stations are important aspects of train operations, these actions should follow the confirmation of the train's exact location. Checking the train's speed could be relevant in certain contexts but does not directly contribute to determining its location, which is the primary concern in this scenario. Therefore, the first priority must be to accurately ascertain the train's position and relay that information to the RCC.