What must trains adhere to when approaching a Speed Limit Sign?

When trains approach a Speed Limit Sign, it is essential for them to proceed at the speed indicated on the sign until the entire train has passed the Resume Speed Sign. This is crucial for maintaining safety on the tracks, as speed limits are established based on various factors such as track conditions, curves, and surrounding environment. Adhering to this guidance ensures that the train does not exceed the safe operating speed and mitigates the risk of accidents or derailments.

Once the entire train has cleared the Resume Speed Sign, it is then safe to accelerate back to higher speeds, provided that it does not exceed any other speed limits that may be in effect. This sequence helps maintain a consistent and safe flow of train traffic, which is fundamental in railway operations.

The other answers present options that do not align with standard operating procedures for train handling and safety protocols. Stopping immediately at a signal can lead to unnecessary delays and potential hazards, while proceeding at maximum speed or ignoring the sign undermines the importance of adhering to established speed limits.