A front door also needs an automatic rim latch
lock, sometimes called a nightlatch.
A traditional Yale-type rim latch
is not enough to secure a front door on its own; ideally it should also have a 5-lever mortice deadlock made to British Standard (BS) 3621 or the equivalent European Standard EN12209.
You will need to order the next higher assembly, the rim latch
, NSN 5340-01-285-0619.
"If they have a mortice lock as well as a rim latch
lock it means I can't get out of the house because I can't unlock the door.