What should be activated during an emergency to stop the train?

Activating the emergency feature on the ETD (Electronic Train Management System) is crucial during an emergency to stop the train effectively. When the red cover is lifted and the emergency is activated, it communicates with the train's braking system to engage the emergency brakes, ensuring the train can stop as quickly and safely as possible.

This procedure is specifically designed for emergencies, allowing the crew to take immediate action in critical situations that require rapid response. The ETD system is integrated into the train's overall safety protocols, providing automated braking when needed, which is essential for preventing accidents or mitigating their impact.

The other options may not provide the immediate response required in an emergency situation. For example, pressing the emergency relay button may be a valid action, but using the ETD is specifically tailored for stopping the train. Reducing speed by 5 MPH or engaging dynamic brakes can be useful under normal operations but are insufficient for quickly halting the train during an emergency.