What must a train do if it encounters an improperly displayed signal?

When a train encounters an improperly displayed signal, the appropriate response is to regard it as showing the most restrictive indication. This procedure is crucial for maintaining safety on the railway. The rationale behind this response is that a signal can be improperly displayed due to a malfunction or other issues, which might compromise the safety of train operations. By treating the signal as indicating the most restrictive condition, the train crew is ensuring that they are acting with the highest level of caution, minimizing the risk of accidents or collisions.

This approach aligns with the operating principles of ensuring safety above all else. It is a preventative measure designed to protect not only the train and its crew but also other trains and infrastructure on the railway network. Safe practices dictate that if there is doubt about a signal's indication, erring on the side of caution is vital, and interpreting the signal as the most restrictive option is the best way to do that.

This strategy emphasizes the importance of strict adherence to safety protocols in train operations and reflects the critical nature of communication and signal integrity on the railway.