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Glossary

Anti-lift device. Device which prevents a door or window from being lifted in its aperture, where this lifting would decrease the effectiveness of a lock or enable the door/window to be removed.

Barrel bolt. Surface mounted fastener with a sliding part that is usually manually controlled and that secures a movable component to its frame or opening. The shoot is provided with a knob, loose key or similar for operation by hand.

Bolt (1). Movable part of a lock or latch that usually engages a component fixed to a frame and is withdrawn into the case,

Bolt (2). Fastener with a sliding part that is usually manually controlled and that secures a movable component to its frame or opening, the sliding part being provided with a knob, loose key or similar for operation. It may be surface mounted, or morticed.

Certified. A product subjected to a testing and ongoing audit programme by a MLA approved organisation.

Deadlock. Lock that contains only a deadbolt.

Escape lock. Deadlock that can be opened (even when locked) from the inside by a single action without use of a key.

Escutcheon. Surround with a shaped hole, with or without a pivoted cover plate, primarily to protect the door leaf from abrasion damage caused by key insertion. This could be for decorative purposes or to increase the security of the locking device.

Flush bolt. Recessed (flush) fastener with a sliding part that is usually manually controlled and that secures a movable component to its frame or opening, the moving part being provided with a lever, slide bar or knob.

Hasp and staple Two-piece fastening for doors which can be secured by a padlock. The hasp could be attached to a fixed or swivel bar.

Hinge bolt. Fixed projection on the hinge side of the door or window. The projection engages into a keep when the door or window is closed. Also known as dog bolt

Latch. Self engaging device, usually operable from both sides, which holds a door or window in the closed position and is released by hand without the use of a key.

Lock. Fastener that combines within one case a latch operated by a handle and a deadbolt which secures the door or window in the closed position

Mortice lock/bolt. Lock/bolt where its body is fitted in a mortice cut into the closing edge of the door or window.

Multi-point lock. Lock that has a latch bolt and a number of other bolts positioned remote from the lock case but connected by rods, which are thrown by means of a single action.

Night latch. Latch with a single bevel latch bolt that is operated internally by a knob and externally by a key which automatically engages when the door is shut.

Night vent or ventilation position. Position in which the door or window can be secured whilst slightly ajar. This usually offers only limited security.

Padbar A device spanning the full width of the door opening with supporting brackets or staples fixed to the frame and secured by a padlock

Padbolt/padlock bolt. Door bolt which can be secured in the locked position by means of a padlock.

Rim lock/bolt. Lock/bolt for fixing on the face of a door or window.

Security bolt. Mortice or barrel bolt which can only be withdrawn by the use of a key.

Security screw. Screw designed so that it either cannot be removed when fixed or which requires a restricted access tool to remove it.

Strike plate. Flat metal plate, appropriate to the latch or lock, fixed to a frame to engage a bolt(s).

Throw - bolts with linear movement - Distance that the dead bolt travels from the fore end of the lock in an outward direction under the action of a key, measured perpendicular to the fore end.

Throw - hook bolts with arctuate movement. - Distance from the tip of the bolt travels from the unlocked to the locked position measured parallel to the fore end of the lock.