What should an employee do if they do not understand a signal?

When an employee encounters a signal they do not understand, the appropriate action is to call for clarification before taking any action. This approach emphasizes the importance of safety and communication within the rail operations environment. Signals are critical indicators of the conditions ahead, and misinterpreting them can lead to unsafe situations, accidents, or disruptions in operations.

By seeking clarification, the employee ensures that they fully comprehend the meaning of the signal and can act accordingly. This practice aligns with the fundamental principles of maintaining safety on the railway, where clear understanding and communication are vital. Taking any action without clarity can lead to unintended consequences, such as assuming a signal means one thing when it actually requires a different response.

The other options could lead to serious safety risks. Acting as if it's a proceed signal without understanding could result in moving forward into a dangerous situation. Ignoring the signal entirely neglects the indication meant to guide the crew, while assuming the signal is for another crew member can lead to miscommunication and potential accidents. Being proactive about understanding signals plays a crucial role in the effective operation and safety of rail systems.