My daughter has just phoned me up because she's locked in her flat, my son was staying with her, has gone out earlier and locked the front door with the mortice lock from the outside. It's simply because he's not used to the flat and locked the door 'automatically' as he went out.
Yes, OK, my daughter should have a key but she can't find it at the moment.
It's not a disaster at the moment because there is no danger, only some inconvenience, but the safety implications do worry me slightly.
What is the accepted/normal/safe way of dealing with this? Are there any sorts of locks one can have which are secure but always enable the door to be opened from the inside in an emergency? Alternatively is there a way of guaranteeing an accessible key?