Abrasive Hard granular material of varying particle size, used in grinding and/or polishing, or incorporated in non-slip surface coatings.
Active Leaf First opening leaf of a pair of doors and usually houses the lock or latch.
Addendum Changes made to the specification.
Active Door (in a pair of doors) The leaf that opens first and the one to which the lock is applied.
Alcove A recessed space connected with or at the side ot a large room.
Alloy The combination of two or more metal elements to achieve special strength, hardness, corrosion resistance or appearance characteristics.
Anneal To heat metal, glass or other materials above the critical or recrystallisation temperature, then cool it to eliminate the effects of colour working, relieve internal stresses or improve electrical, magnetic or other properties.
Anodic Coating The surface finish resulting from anodising. See anodise.
Anodise To provide a non-corrosive oxide film on the surface of a metal, particularly aluminium, by electrochemical action. Anodising is available in varying colours, as well as natural, for decorative purposes.
Anti-Friction Bearing A bearing used in a hinge for the purpose of reducing friction and improving efficiency. Normally balls, oil-impregnated or other anti-friction material is used.
Anti-Friction Latchbolt A latchbolt equipped with a device for reducing friction between the bolt and strike. Usually a small trigger attached to the bolt contacts the strike and exerts a lever action to depress the bolt. Generally incorporated in longer throw latchbolts.
Approved Schedule A schedule reviewed by the architect and stamped as approved.
Arch A curved structure that carries the weight over an opening.
Architect A person who plans buildings and oversees their construction.
Architectural Hardware A part of the decorative and functional treatment of the building, its rooms and its door openings.
Astragal A member or combination of members applied to one or both doors of a pair at their meeting edges. The astragal closes the clearance gap for the purpose of either providing a weather seal, minimising the passage of light between the doors or retarding the passage of smoke or flame during a fire.
Attack Protection Components incorporated in locks and/or lock cylinders which are designed to increase security against manipulation by picking, raking or drilling.
Automatic Deadlatch See Deadlatch.
Authorised Key Cutter A business or person authorised by the lock manufacturer or agent to cut or bit that manufacturer’s or agent’s restricted keys.
Auxiliary Bolt An additional bolt which is activated by the strike when the door is closed automatically deadlatching the latchbolt against end pressure.
Auxiliary Lock A lock having a latchbolt or a deadbolt operated by a key or a turnsnib, or both. This type of lock is often used in addition to another lock, which may or may not be key operated, but which has a latchbolt operated by knobs or levers.
Auxiliary Spring A device or an accessory containing a hub and a spring to prevent the sagging of lever handles.