A new door system and related technology for a passenger carrying rail vehicle, such as a President's Conference Committee (PCC) streetcar rail vehicle, and a method for retrofitting a rail vehicle door system with the new door system. In some embodiments, the new door system includes an electro-mechanical angle drive motor, a solid door control pivot rod, a door leaf panel clamp that is permanently connected to the solid door control pivot rod, a lever arm that includes a positive locking device and that is coupled to the solid door control pivot rod, and a connecting rod that is attached to the electro-mechanical angle drive motor and to the lever arm to enable the connecting rod to impart motion generated by the electro-mechanical angle drive motor to the lever arm.

A controller is configured to perform a process including operating or releasing an electrically driven hermetic retention device configured to retain airtightness between a door and an opening of a railway vehicle, according to whether or not there is a possibility of an opening operation of the door within a predetermined period.

An expandable safety gate for a vehicle door opening comprising a first substantially rectangular frame and a second substantially rectangular frame slidingly engaged in the first frame such that the two frames are positioned in the same vertical plane, the second frame being extendable from the first frame to fit within the door opening; and locking mechanisms to secure the second frame in its extended position within the vehicle door opening, wherein safety gate is comprised of non-conductive material.

When a side sliding door is in a fully closed state, there is a space between a first elastic structure and a second elastic structure, and a first projecting wall portion and a second projecting wall portion are located so as to overlap each other when viewed in a thickness direction of the side sliding door. An elastic fin includes: an attaching portion detachably attached to one of the first elastic structure or the second elastic structure; and a fin portion projecting from the attaching portion. When the side sliding door is in the fully closed state, the fin portion contacts the other of the first elastic structure or the second elastic structure.