TransLink studying platform screen doors for SkyTrain stations

TransLink studying ways to limit SkyTrain track intrusions, including the installation of platform screen doors

Artistic rendering of platform screen doors installed onto the platforms of an existing London Underground station. (Transport For London)

In an effort to improve safety and reliability on SkyTrain, TransLink is now executing a study that will consider a wide range of options that limit track intrusion onto the railway system.

TransLink spokesperson Dan Mountain told Daily Hive Urbanized on Tuesday the current Trackway Intrusion Engineering Study includes an analysis on the feasibility of platform screen doors, which are commonly found on Asian and new rail public transit systems.

Platform screen doors are physical barriers, typically glass walls, that physically prevent people and other objects from falling into the tracks at stations. Automated sliding doors align with the doors of the train to enable passengers to disembark and board.

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The purpose of the study is to examine the current state of the track intrusion system, and research how peer systems around the world limit track intrusion, including looking at technologies, processes, and policies. The outcome of the study will provide recommendations to limit track intrusions, and identify potential ways to best maintain the current track intrusion systems.

“The recommendations from this study will help inform a long-term, track-intrusion plan,” stated Mountain, adding that the study is currently in the early stages, and expected to be completed in 2025.

Track intrusion generally means the entry of foreign objects, especially humans, onto the track.

Track intrusion alarms are found where track intrusions are most likely — along the length of SkyTrain station platforms.

Platform level of SkyTrain’s Brentwood Town Centre Station. (Kenneth Chan/Daily Hive)

Given that SkyTrain is a fully-automated, driverless system, effective track intrusion alarms are absolutely paramount for safety.

On the original 1980s and 1990s-built Expo Line segment between Waterfront and King George stations, the track intrusion alarms at stations detect foreign objects using a system of weight-sensing pressure plates that line the length of the track within stations.

For the stations built as part of the Millennium Line in the 2000s and 2010s and the Canada Line, a web of infrared sensors provide a comparatively more high tech track intrusion alarm solution.

When track intrusion alarms are triggered at a station, incoming trains automatically come to a halt, sometimes very suddenly if the train is already in very close proximity to a station or has already entered the platform.

But there are limitations to how fast a train can be suddenly stopped, with such a motion potentially injuring passengers onboard.

There is a very high human cost when tragic circumstances arise from individuals falling into the immediate path of an incoming train — not only for the direct victim, but also the long-term mental well-being of passengers who witness such incidents, and the deployed SkyTrain attendants, maintenance crews, and emergency responders.

As well, such incidents also have an immense impact to the regional public transit network, with particularly tragic incidents requiring up to hours of major service disruptions.

Track intrusion alarms can also be triggered by personal belongings and garbage, which adds to delays. In other cases, there are false alarms.

SkyTrain Mark I cars. (Kenneth Chan/Daily Hive)

In 2021, TransLink completed the installation of 265 guideway cameras on the platforms of the Expo and Millennium lines to cut down the response times to intrusion alarms, allowing the SkyTrain control room to give an “all-clear” after a flag instead of solely relying on deploying SkyTrain attendants to visually inspect a platform.

As the region’s SkyTrain network grows in length — with the opening of the Millennium Line’s Broadway Extension to Arbutus and eventually UBC, and the Expo Line’s Surrey-Langley Extension — and as more regional residents depend on SkyTrain to move around, the resiliency, reliability, safety, and capacity of the system deserves greater attention.

Platform screen doors, which are sliding glass barriers affixed to the edge of station platforms, are generally the most common effective solution in the world to eliminate track intrusion issues. They also help maximize waiting area capacity on the platform, as passengers can safely stand next to the protected edge.

TransLink’s new study also coincides with the forthcoming retirement of 150 old Mark I cars from the 1980s and early 1990s, and the retirement of the initial batch of Mark II cars that entered service in the early 2000s in time for the opening of the Millennium Line.

Daily Hive Urbanized has covered the feasibility of installing platform screen doors on SkyTrain on two other separate occasions over the past decade, and each time TransLink explained the main challenge on the Expo and Millennium lines is its diverse fleet of varying generations of cars.

The original Mark I cars, in particular, have a wildly different door spacing than the subsequent generations.

But with the major fleet of Mark I cars being fully retired between 2024 and 2028 and the retirement of the initial Mark I fleet in the early 2030s, the technical feasibility of installing platform screen doors will likely improve.

A Mark III train at SkyTrain Edmonds Station. (TransLink)

2023 updated artistic rendering of the Mark V SkyTrain car. (TransLink)

The Mark I cars will be replaced by an order of 205 new generation Mark V cars (41 five-car-long trains), which will arrive between late 2023 and 2028. These Mark V cars are essentially an upgraded version of the Mark III cars, which is the newest generation in current use. TransLink also holds options to order more Mark V cars beyond its current order, which would give the fleet on the Expo and Millennium lines even more uniformity.

By 2032, the Mark V cars will account for 75% of the total annual mileage of the Expo and Millennium lines, followed by 13% for the four-car-long Mark III trains and 11% for the remaining Mark II cars. In contrast, currently, the Mark I cars account for 31% of the annual mileage, the Mark II cars account for 35%, and the Mark III cars account for 33%.

Installing platform screen doors wide enough to fit all types of door spacings across the generations of trains would leave a large, dangerous gap between some trains and the platform screen doors.

However, this challenge is not unique to SkyTrain, and some manufacturers are looking to innovate to overcome the door spacing issues of a diverse train fleet. Earlier this year, the world’s first adaptive shifting platform screen doors were installed at a subway station in Osaka on a pilot project basis. The platform screen doors open and close in different positions, depending on the type of train.

And varying door spacings are not an issue on the Canada Line, as this standalone train system separate from the Expo and Millennium lines, but still considered part of the region’s SkyTrain network, has just one model of car fleet. But the need to renegotiate with SNC-Lavalin to amend their operating and maintenance contract for the Canada Line would likely be an added barrier. SNC Lavalin’s contract expires in 2040.

Installation process for platform screen doors on Montreal’s new REM train system. (Alstom)

It is far easier and cheaper to install platform screen doors on a brand new train network, given the unique design specifications required to accommodate such equipment. Platform screen doors will be a key safety feature of Montreal’s new automated REM network, which is expected to see its first phase open later this year, and Toronto’s new automated standalone Ontario Line, which is scheduled to open in 2031.

In 1994, BC Transit, the predecessor to TransLink, studied the feasibility of installing platform screen doors on the Expo Line.

At the time, this previous study determined extensive retrofits would be required for the Expo Line platforms, including rebuilding the station platform edges to support the heavy weight of the platform screen doors, modifications to the ceiling line to provide an anchor to the new walls, redesigning the ends of the station to include a full wall enclosure, new electrical power distribution systems, modifications to ensure sufficient ventilation in the stations, changes to the automated train control system, and the disconnection and removal of the existing track intrusion systems at the platforms.

There would also be lengthy service disruptions to modify the stations and install the platform screen doors.

platform screen doors london underground

Artistic rendering of platform screen doors installed onto the platforms of an existing London Underground station. (Transport For London)

But platform screen doors are increasingly the standard for both new and existing rail public transit systems.

For example, Transport For London has plans to progressively install platform screen doors for many of its old London Underground stations.

In January 2023, the Toronto Transit Commission’s (TTC) new 15-year capital plan through 2037 included a program to install platform screen doors for every subway station at an estimated cost of $2.9 billion. This project is currently unfunded.

And in early June 2023, the TTC announced new details about the $1.5-billion retrofit and expansion of Bloor-Yonge Station, including the installation of platform edge doors for the Line 1 subway platforms. This will be one of the first planned platform screen door retrofits to an existing train system in North America.

Artistic rendering of the trains and platform screen doors of Toronto’s new Ontario Line. (Metrolinx)

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