Abstract: A security closures are adapted to be secured over windows or other openings in a wall of a building. The security closures are fixed to the building in a manner to substantially prevent removal of the closure from the exterior of the building. On the other hand, the security closures provide ways to secure the security closures from the interior of the building while minimizing any obstruction to work being done inside the building.

Abstract: A security closure for covering an opening, e.g., a window, in a building includes a panel having a circumferential sidewall. A support member is securable to extend across the opening in fixed relation thereto, the support member being releasably securable to the interior of the panel away from one edge thereof by a releasable securing device. The support member is fixed at the one edge by a hinged fixing structure which allows the panel to pivot substantially along the one edge away from the opening when the support member is released from the releasable securing device. As a result, an emergency release of the panel can be accomplished.

Abstract: A locking mechanism for security door assemblies, in particular but not exclusively, to a security door assembly which is fitted temporarily on a building. The locking mechanism for such a security door comprises a locking member movable between a locking state and non-locking state. A lock releasably engagable with the locking member prevents the locking member moving to the non-locking state. The lock mechanism further includes an operating device that is coupled to the locking member by a connecting structure which includes a force limiter. The force limiter limits the force the operating device can apply to the locking member without damage to any of the parts of the locking mechanism.