What should be the response if an engineer cannot see a signal while pushing cars?

The appropriate response when an engineer cannot see a signal while pushing cars is to stop the movement immediately. This procedure is vital for ensuring safety on the tracks. Signals are critical for communication between the railway infrastructure and the train crew, providing essential information regarding track conditions, speed limits, and potential hazards ahead.

If an engineer cannot see a signal, it indicates a lack of clear information about the upcoming track status, which could pose safety risks, such as running into a stop signal or encountering unexpected obstacles. Stopping immediately allows the engineer to reassess the situation and safely communicate with the crew and any relevant control personnel to determine the next steps, ensuring that any movement made afterward is informed and secure.

The other options, while suggesting precautionary measures, do not prioritize safety effectively in cases where visibility is completely compromised. Reducing speed and proceeding with caution could still result in unsafe conditions if the engineer does not have signal information. Continuing to move while checking visibility is also unsafe and could lead to accidents. Alerting other crew members might be necessary, but it should only follow the immediate step of halting movement to prevent any risks.