You know, “hatch”. But it’s funnier saying door. Could a ship just dock with it, equalise pressure, and open the hatch? Or is there some sort of security? I tend to think ‘no’ because of a macabre situation where the crew are dead and the station is being recovered. But it’s amusing to think in space they don’t need to keep the doors locked.
When they eventually deorbit the space station they’ll need a way to close and lock the door from the outside when everyone else is out.
Yes, they won’t need an atmosphere if there are no people on board but undocking the station side hatch open would cause it to vent the atmosphere and anything not tied down. This could cause the station to spin uncontrollably and potentially do damage to the return craft with the crew on board.
So there must be some sort of way to manipulate the lock from the outside on at least one of the docking ports.
This would also be necessary in an event where they needed to evacuate the station.