What procedure must be followed to transition into ATC Bypass mode?

Transitioning into ATC Bypass mode involves a specific procedure to ensure safety and compliance with operational protocols. The correct procedure is to break the seal on the Bypass switch with the appropriate authorization. This step is critical because it prevents unauthorized access and helps maintain operational integrity. The process of breaking the seal indicates that necessary precautions and protocols have been followed, ensuring that the train operates in a safe manner under the bypass conditions.

Each action within this procedure is governed by safety regulations, thus requiring proper authorization before activating the Bypass mode. This emphasizes the importance of communication and control within the train operation framework.

Other options, while they may seem relevant in emergency contexts, do not align with the established protocol for transitioning into ATC Bypass mode. Immediate activation of emergency brakes or proceeding without notifying relevant personnel would not only jeopardize safety but also violate operational procedures. Calling for permission from other engineers captures a collaborative approach but does not align with the necessary established protocol regarding the Bypass switch. Therefore, breaking the seal with authorization is the correct procedure.