Air Transfer Grille (fire and smoke)

A device that will allow the passage of air in normal use, but when activated will contain both ‘cold’, i.e. ambient smoke and hot gases – usually activated by heat and an electrical interface with the detection and alarm system.


As Low As Reasonably Practicable; a key concept in fire safety and in particular fire risk assessment, based on the Law of Diminishing Returns, whereby risks are reduced until a point is reached where the cost to reduce the risk further would be disproportionate to the benefit achieved.


An opening in a door created for a vision panel, ventilation grille or letter box.


A decorative moulding that conceals the gap between the edge of the frame and the surrounding structure (substrate). ART: Approved Repair Technique.


Available Safe Egress Time.


Association for Specialist Fire Protection.

Automatic Door Release Mechanism

A device that will automatically release either a locking mechanism on an exit route or a hold-open device to a door or roller shutter. It should operate on the actuation of the fire warning or detection system, or on failure of the power supply and be able to be manually overridden.



The moulding that frames and retains a door’s vision panel.

Bolster Software

A building surveying and inspection system.

Bottom Edge Gap

Please see ‘Threshold Gap’.


The Building Research Establishment; a former government national laboratory, now part of a charitable organisation called the BRE Trust.



An independent third-party certification scheme, operated by Warrington Fire, that audits performance, quality, reliability and traceability of products and systems.

Compartment (fire)

Part of a building, comprising one or more rooms, spaces or storeys, constructed to prevent the spread of fire and its effects to, or from, another part of the same building, or an adjoining building. (A roof space above the top storey of a compartment may be included in that compartment).

Compartment Wall

A fire-resisting wall used to separate one fire compartment from another; typically designed and intended to have a minimum period of fire resistance of 60 minutes (or 30 minutes in singlestorey buildings).

Core (of door)

The internal composition of a door leaf.


Doorstop (timber)

A rectangular or square length of wood that prevents the door from closing beyond its jamb.



A general term for a decorative plate.


Final Exit

The termination of an escape route from a building, intended to give direct access to a place of ultimate safety outside the building.

Fire (resisting) door

A door or shutter provided for the passage of persons, air or objects, which, together with its frame and furniture, is intended when closed to resist the passage of fire and/or gaseous products of combustion and is capable of meeting specified performance criteria to those ends. It may have one or more leaves, and the term can sometimes include a cover, hatch, or other form of protection to an opening in a fire-resisting wall, floor, fire barrier or ceiling, or in a structure surrounding a protected shaft.

Fire Doorset (or ‘door set’)

A door assembly, tested as a single unit and supplied, from one source, as a complete, warranted, entity.

Fire Integrity

The extent over a given time that a component, such as a fire door, can withstand and prevent fire as well as smoke from breaching the barrier. The letter for denoting integrity in fire test documents is “E”.

Fire Resistance (of a fire door)

The ability of a door to fulfil, for a stated period of time, the required fire integrity and thermal insulation as expected in a standard fire resistance test.

Fire Stop (or ‘firestop’)

A seal provided to close an imperfection of fit or design tolerance between elements or components, to restrict the passage of fire and smoke.

Fire Safety Order (or ‘FSO’)

An abbreviation of The Regulatory Reform (Fire Safety) Order 2005, which is also commonly referred to as the RRO.

Flush Bolt

A sliding bolt let into the face or edge of a door, so as not to be proud of the leaf.

Forend (face plate)

The visible part of a latch or lock mechanism once it has been morticed into the door, through which the latch or bolt protrudes.


Global Fire Resistance Assessment (GFRA)

A comprehensive document produced by a UKAS or equivalent approved organisation using established methodology, to determine the limits of manufacture and design and extend the scope of application in order to satisfy fire resistance performance based on various fire tests carried out, typically to BS 476-22 or BS EN 1634-1.

Golden Thread of Information (for fire doors)

An accurate, linked record of a fire door’s specification, fire test evidence and certification and all the information required to ensure traceability and that it has been installed to comply with Regulation 7 of the Building Regulations and can be maintained to comply with Regulation 38 of the Building Regulations and Article 17 of the FSO.



Institute of Healthcare Engineering and Estate Management.

Intumescent Material

A product that swells as a reaction to fire (heat).



The side-post or lining of a doorway or other aperture.



The Loss Prevention Certification Board; sometimes referred to as the Loss Prevention Council; part of the BRE Trust.

Ligature Point

In the context of mental healthcare setting, an anchorage point used to facilitate a suicide attempt.


Loss Prevention Standard (as in LPS 1197).


Other names for an internal door frame.


Material used to create the door edge, covering and protecting the core.


Panic Exit Device

A bolt and latch system, which should conform to BS EN 1125, operated by either a cross bar or touch bar on the inside of the door for opening a final exit door.


Personal Emergency Evacuation Plans; that is intended, in the event of a fire evacuation, to ensure persons who require assistance can escape safely.

Pesola Gauge

A spring scale that measures ‘push and pull’ opening force on a fire door, measured in Newtons.

Primary Test Evidence

A report based on a physical fire test of a manufacturer’s doorset carried out by an independent 3rd party accredited test house.

Progressive Horizontal Evacuation

An evacuation strategy, typically used in healthcare buildings, but sometimes applicable in other types of buildings when patients, staff and other relevant persons are moved away from a fire into a fire and smokefree compartment or sub-compartment, of relative immediate safety, typically on the same level of the premises.

Protected Stairway

A stairway discharging through a final exit to a place of safety (including any exit route between the foot of the stairway and the final exit) that should be adequately enclosed in fire-resisting construction.



Please see ‘Fire Safety Order’.

Rebated doors

A double doorset, with door leaves having machined edges to create a partial overlap where the leaves meet.


An area designed and intended as a place of temporary safety within a building. This may be an adjoining compartment, sub-compartment or lobby, capable of holding all those threatened for a given period, from which there may be potential for further unassisted escape should that become necessary.


Smoke Seal Door

An internal door strategically located in premises to effectively restrict the passage and spread of smoke, including ambient, cold smoke and noxious fumes to other areas of the building.


The sides of a door leaf, with the hanging stile being the hinge side, the leading stile (as in ‘leading edge’) on the opening side and the meeting stile being where double or leaf and a half doors meet.

Strike plate

A metal plate fixed to a door jamb with a hole for the bolt of the door. This protects the jamb against friction from the bolt and increases security in the case of a jamb being made of a softer material such as wood.


Areas into which the building can be divided to reduce travel distance and which are designed and intended to provide 30 minutes’ resistance to fire.

Sub-compartment wall

A fire-resisting wall used to separate one sub-compartment from another, having a designed and intended minimum period of fire resistance of 30 minutes.


Threshold Gap (door)

The gap between the bottom of the door and the floor. Sometimes also referred to as the ‘bottom edge gap’.


A horizontal structural beam or bar, or a crosspiece separating a door from a window above it.



The UK’s National Accreditation Body, responsible for determining, in the public interest, the technical competence and integrity of organisations offering conformity assessment services such as testing, calibration, inspection and certification.