“Tenders have been floated to provide automated half-height platform gates at all Metro stations of Line 7 and Line 8 of Phase III. The platform gates will be installed at the platforms on build-operate-transfer basis. The signalling system will be based on communication-based train control (CBTC) implementing driverless or unattended train operation,” a Metro spokesperson said.

Line 7 (Mukundpur-Dhaula Kuan-Maujpur-Shiv Vihar) has 38 stations, while Line 8 (Janakpuri West- Kalindi Kunj-Botanical Garden) has 25. Officials said six-coach trains will run in these corridors.

Screen doors act as protective barriers, separating the commuters standing on platforms from tracks. These automated gates will be around 1.7-metres (5.6 feet) high — the average height of a man.

The planned height would allay fears of overheating at underground sections, officials said.

Earlier, Delhi Metro chief Mangu Singh had said the platform screen doors might not be feasible at all stations. “The Metro tunnels need ventilation, and will become overtly heated if there are platform screen doors at all stations. But at crowded stations like Rajiv Chowk and Kashmere Gate, which handle footfalls of over 5 lakh commuters daily, it can be useful,” he said.

Delhi Metro considered the proposal to install the screen doors, despite being an expensive proposition, following a spate of suicides on the tracks at stations and people getting stuck in train doors.

“The device will be installed at every Metro station in underground, elevated and surface sections. The doors will be roughly of the same height of the rolling stock. This will enable proper ventilation and prevent overheating of the underground tunnel. The exact design of the automated doors will be known after the bids are finalised,” an official said.

Installation of the screen doors will prevent incidents of passengers falling on the track because of overcrowding and help contain suicide cases.

Phase-III, which expands Metro connectivity by another 119.95 km, runs through a large section of Outer Ring Road and Ring Road. It is expected to attract a higher footfall.

With the completion of Phase-III, the projected ridership figure for Delhi Metro is 39.50 lakh commuters in 2016.

The gates will be used to generate advertisement revenue.