This standard is intended as a basis for specifying the dimensions of mortice locks, tubular frame locks and multipoint locks, including their striking plates, as well as rules for dimensioning such locks in order to ensure their compatibility with other components that can be used in combination with the door. Components covered by the specifications pertaining to compatibility include - locking cylinders according to DIN 18252; - door lever handles, backplates and escutcheons according to DIN 18255; - door lever handle units for fire doors and smoke control doors according to DIN 18273; - security plates according to DIN 18257.