In an ongoing effort to improve the New York City subway system, the L Train has been subjected to a series of tests by the MTA. New fold-up seats have recently made their debut and another feature may soon been introduced. According to amNewYork, the MTA will test platform doors on the L Train’s Third Avenue station.

The design is being tested following advocacy from board members and experts. Already utilized in other subway stations around the world, including in Paris and Seoul, the doors are intended to prevent commuters from falling onto the subway tracks.

“We’re in the design planning stages and working to overcome structural challenges for a small platform screen doors pilot at the Third Avenue Station along the L line,” said an MTA spokesman in a statement.

At the moment, the agency has not provided much information about the doors. However, Curbed NY notes that they will be installed during the L train shutdown, which will take place in April 2019. Thus far, the MTA has been “unreceptive” to the widespread use of platform doors, citing the age of the subway system and its lack of uniformity as the main issues preventing their installation. The MTA mentions four specific obstacles, including the space for an equipment room; curved tracks at stations; physical obstructions, such as columns, and the need for adequate power (not to mention the overall cost of project).

The Third Avenue station and L train cars, which are all the same models, were specifically selected for this trial run as they present fewer issues. If successful, the doors could debut in 2020, when the lines reopens.

Next, see A Sneak Peek at the MTA’s New Open Gangway Subway Car Prototype and read about the Phase Out of the Metrocard.