TN 303.2- Subway Emergency Power Cuts

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Questions and Answers

What is the purpose of shutting down power at track level to the traction power rail?

To perform routine maintenance on the traction power rail

To respond to an emergency situation at track level (correct)

To allow personnel to travel along the track safely

To increase the power supply to subway trains

Where are Emergency Alarm Stations located?

At the ends of all Subway and Rapid Transit platforms, and at 150-metre intervals in track level tunnels and open cut sections (correct)

Only in track level tunnels and open cut sections

Near exit points only

Only at the ends of Subway and Rapid Transit platforms

What is the purpose of the blue lights at each EAS?

To identify the location of the EAS (correct)

To signal an emergency

To provide lighting in dark tunnels

To indicate whether the power is on or off

What contains a PAX phone and an emergency power cut/trip device?

Emergency Alarm Station (EAS) (C) Signup and view all the answers

What happens when an EAS emergency power cut/trip device is activated?

Power is cut to both tracks, in both directions (D) Signup and view all the answers

What information is displayed above each EAS at track level?

The distance to the closest exit in green, the distance to the alternative exit in yellow, the EAS identification number, and the power cut/trip number (B) Signup and view all the answers

What happens to power in adjacent storage tracks during an emergency?

It is cut (D) Signup and view all the answers

What is the purpose of PAX phones in subway tunnels and stations?

For internal communication (A) Signup and view all the answers

What should firefighters use to report their location at an emergency scene?

The information on the PAX phone (A) Signup and view all the answers

What is the function of Power Control in the TTC Transit Control Centre?

To monitor electrical substations (B) Signup and view all the answers

What step should be taken before proceeding from platform level to track level during an emergency?

Locate the EAS and utilize the PAX phone (B) Signup and view all the answers

What happens to vehicle movement in the area after a power cut/trip?

It stops (B) Signup and view all the answers

Why should firefighters leave the PAX phone off the hook?

To keep the line open with TTC staff (C) Signup and view all the answers

What should firefighters be aware of regarding track switches?

They can create a pinch hazard (A) Signup and view all the answers

How long do trains have backup power after a power cut?

3 hours (D) Signup and view all the answers

What happens to passengers on a train in a tunnel when power is cut?

Evacuation of passengers may be required (C) Signup and view all the answers

Study Notes

Emergency Procedures in the Subway System

An emergency power cut/trip is the process of shutting down power at track level to the traction power rail (third rail), which powers subway trains.

Emergency Alarm Stations (EAS)

EAS are located at the ends of all Subway and Rapid Transit platforms and at 150-metre (500 ft.) intervals in track level tunnels and open cut sections.
Blue lights identify the location of every Emergency Alarm Station.
Each EAS contains a PAX phone and an emergency power cut/trip device.
The emergency power cut/trip device is a power disconnect that disengages the traction power rail (third rail) power breakers.

Types of Emergency Power Cut/Trip Devices

There are three types of Emergency Power Cut/Trip Devices that immediately cut power on both tracks in both directions and to adjacent storage tracks.
A visual and audible alarm is triggered at TTC Transit Control Center.

PAX Phones

PAX is an abbreviation for 'Passenger' and refers to phones spaced throughout subway tunnels and stations for internal communication.
To call any internal TTC phone, dial the last four digits of the number (e.g., '3555' for TTC Transit Control Centre).
Firefighters should use the information on the PAX phone when reporting their location at an emergency scene.

Power Control

Power Control, located within the TTC Transit Control Centre, controls the Subway ventilation system and monitors electrical substations that generate and distribute 600 Volt DC traction power.
Power Control advises on the extent of power cuts and when vehicle movement in the area has stopped.

Emergency Power Cut/Trip Protocol

Locate the EAS and utilize the PAX phone to connect with TTC Transit Control Centre before cutting power.
Provide name, position, location, and reason for the power cut/trip to TTC Transit Control Centre.
TTC Power Control advises on the location and ensures that vehicle movement in the area has stopped.
Record the name of the TTC staff confirming the power cut/trip.
Leave the PAX phone off the hook and transmit via radio to the TFS Incident Commander or TFS Communications that power has been cut.
Activate the power cut/trip at each EAS when traveling further into the tunnel.

Safety Precautions

The power traction rail (third rail) should always be treated as live.
Firefighters should remain between the running rails and be aware that track switches can continue to operate, even with power cut, creating a severe pinch hazard.

Emergency Backup Power on Trains

Trains have three hours of backup battery power after the power cut, which powers emergency systems, lights, heating, and air conditioning but does not allow the train to be moved.
TTC will attempt to stop trains at station platforms for ease of evacuation.