What must the train engineer do to start train movement in MATC?

To initiate train movement in a MATC (Multiple Aspect Train Control) system, the train engineer must depress the ATC Start button after ensuring that all doors are properly secured. This procedure is crucial because it activates the train control system that monitors various operational parameters, ensuring that all safety protocols are adhered to before the train begins its journey. The ATC system helps prevent accidents by managing speeds, stopping distances, and monitoring compliance with operational signals.

Securing the doors is a fundamental safety step, as it prevents potential accidents that could occur if passengers are not safely inside the train before departure. Therefore, the action of depressing the ATC Start button directly relates to engaging the safety mechanisms within the train's operation. This aligns with the stringent safety protocols that are paramount in rail operations to protect passengers and operational integrity.