You’re right that a normal toilet can have an appropiate physical handle. Howver normal toilets are easy to push open as they aren’t moving. Opening a large (an

You’re right that a normal toilet can have an appropiate physical handle. Howver normal toilets are easy to push open as they aren’t moving. Opening a large (and thus heavy) swing door, wide enough to allow a chair to get in, manoeuvre, and close, without it smashing back when the train lurches, doesn’t work, meaning a sliding doors which isn’t appropriate. As such the solution is an electronic sliding door (as many couldn’t provide enough strength over distance to open a sliding door manually), meaning an open/close button Once you have that feature adding an electric lock makes sense. A physical lock would be trickier to incorporate.