Abstract: A locking mechanism for a vault door having a plurality of independently negatable locks, each one coupled through its bolt to a respective pivoted locking arm. In the locking condition the arms are pivoted to block withdrawal of bars carried by the main boltstraps. Each lock bolt is connected to its arm by a rotatable control member having a lobe and an eccentric peg which engages in a slot in the respective arm. To negate a lock its bolt is thrown and a lever turned to rotate the respective control member. This places the lobe next to the lock case and pivots the locking arm into its unblocking position. If the door is left open with the boltwork withdrawn and unlocked unauthorized negation of a lock cannot take place because there is insufficient space to rotate the respective control member without the latter abutting the lock case.

Abstract: A vault constructed by assembling together, in demountable fashion, a plurality of separate, pre-fabricated panels. Each perpendicular corner of the assembled vault is provided in a panel which extends integrally from the respective corner to define significant portions of both of the adjacent sides of the vault, thereby avoiding the security weakness of separate orthogonally-jointed panels at those corners. In addition each panel comprises a steel plate upon which is cast a barrier material of high penetration resistance but relatively low weight, consisting of fibre-reinforced concrete.