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.

Abstract: A vault or strongroom includes unitary and self-contained equipment for providing life-support within the sealed vault-enclosure. The carbon-dioxide content of the atmosphere within the enclosure is monitored and a pump is operated if the monitored value exceeds a predetermined value, typically 1% or 2%. Operation of the pump pumps air of the atmosphere through material that absorbs carbon dioxide and this, together with operation of a fan to circulate air in the enclosure is continued until the monitored content has been reduced, typically to 0.5%. Oxygen (or air) is released from cylinders for replacing the absorbed carbon dioxide and maintaining an oxygen level of about 18% or 19% in the enclosure. Release of oxygen is regulated by a valve device to maintain a variable--pressure (or oyxgen level)--of the atmosphere within the enclosure substantially constant or within predetermined limits. The pump is operated concurrently with release of the oxygen.