Fire Door Glossary

Approved Document B: Statutory guidance on fire safety for building work in England (Wales publishes its own version). Volume 1 covers dwellings; Volume 2 covers other buildings.
Approved Document M: Guidance on access to and use of buildings. For doors it sets clear widths, vision panels and maximum opening forces.
Approved Document Q: Guidance on security in new dwellings in England, requiring doorsets that give access to a dwelling to meet PAS 24 or equivalent.
BS 476-22: The British test standard for fire resistance of non-loadbearing elements, including doors. It is the source of FD ratings and is due to be removed from Approved Document B on 2 September 2029.
BS 476-31.1: The British test for smoke leakage through doorsets at ambient temperature, behind the S in FD30S.
BS 8214: The code of practice for fire-resisting and smoke control doors. The 2026 edition, published in March 2026, covers timber, steel, glazed and composite doors.
BS EN 1634-1: The European fire resistance test for doorsets, leading to E and EI classifications under BS EN 13501-2.
BS EN 1634-3: The European smoke leakage test for doorsets, leading to Sa and S200 classifications.
BS EN 13501-2: The European classification standard for fire resistance, using codes such as E30, EI60 and E30 Sa.
BS EN 1154: The standard for controlled door closing devices such as overhead closers.
BS EN 1155: The standard for electrically powered hold-open devices that release a door when the fire alarm sounds.
BS EN 1158: The standard for door coordinators (selectors), which make pairs of doors close in the right order.
BS EN 1125: The standard for panic exit devices — push bars — for doors used by the public.
BS EN 179: The standard for emergency exit devices, such as push pads and levers, for doors used by trained staff.
BS EN 1935: The standard for single-axis hinges, including the grades used on fire doors.
Building Safety Act 2022: Legislation creating the Building Safety Regulator and a stricter regime for higher-risk buildings: 18 metres or seven storeys with at least two residential units.
Certificate reference: The number of the third-party certificate that covers a doorset. We put it on every quote so it can be checked.
Compartment wall: A fire-resisting wall dividing a building into compartments. Doors in compartment walls usually need the same rating as the wall.
Door leaf: The moving part of a door. A leaf alone is not a fire door — the rating belongs to the doorset.
Door selector: Another name for a door coordinator, which controls the closing sequence of a pair of doors with rebated meeting stiles.
Doorset: A complete assembly of leaf, frame, seals, hinges and hardware supplied and tested as one unit.
E (integrity): The European classification for a construction's ability to stop flames and hot gases passing through. E30 means 30 minutes.
EI (integrity and insulation): A European classification adding insulation: the unexposed face must stay below set temperature rises.
FD rating: The British shorthand for a fire door's integrity rating in minutes, for example FD30 or FD60.
FD30S: A 30-minute fire door that also restricts cold smoke, using tested smoke seals.
Field of application: The range of sizes, glazing and hardware a manufacturer's test evidence or assessment covers.
Fire risk assessment: The assessment a responsible person must carry out for non-domestic premises and the common parts of multi-occupied residential buildings.
Fire Safety Act 2021: Legislation confirming the Fire Safety Order covers the structure, external walls and flat entrance doors of multi-occupied residential buildings.
Fire Safety Order: The Regulatory Reform (Fire Safety) Order 2005, the main fire safety law for existing non-domestic premises in England and Wales.
Fire strategy: The design document that sets fire resistance and escape requirements for a building, including which doors need which rating.
FIRAS: A third-party certification scheme for installers of passive fire protection, including fire doors, operated by Warringtonfire.
Flat entrance door: The front door of a flat opening onto a shared corridor, lobby or stair, usually required to be FD30S and self-closing.
Flush bolt: A bolt recessed into the edge of a door leaf to hold an inactive leaf closed, usually on cupboard or plant room pairs.
Free-swing closer: A closer that lets a door move freely like an unclosed door until the fire alarm activates it.
Golden thread: The accurate, up-to-date information about a higher-risk building that must be kept under the Building Safety Act.
Hold-open device: An electromagnetic device that holds a fire door open and releases it on alarm.
HMO: A house in multiple occupation — a property let to people forming more than one household who share facilities.
Intumescent seal: A strip in the door edge or frame that swells in heat to seal the gap between leaf and frame.
Ironmongery: Door hardware: hinges, locks, latches, handles, closers, plates and seals.
Leaf-and-a-half: A pair of doors with one wide and one narrow leaf.
LPS 1175: A security standard from the Loss Prevention Certification Board that grades resistance to forced entry.
Meeting stiles: The vertical edges where the two leaves of a double door meet.
PAS 24: A UK security standard for doorsets and windows, commonly used for flat entrance and external doors.
Q-Mark: BM TRADA's third-party certification scheme, including fire door manufacture and installation.
Regulation 10: Part of the Fire Safety (England) Regulations 2022 requiring regular fire door checks in residential buildings with a storey above 11 metres.
Regulation 38: Part of the Building Regulations requiring fire safety information to be handed to the responsible person for relevant buildings in England.
Responsible person: The person with duties under the Fire Safety Order — usually the employer, owner or managing agent.
Riser: A vertical service shaft carrying cables or pipes between floors, closed off by fire-rated doors kept locked shut.
Sa: The European smoke control classification at ambient temperature, as in E30 Sa.
Self-closing device: A closer that returns a door to its closed and latched position from any angle of opening.
Smoke seal: A brush or blade seal that restricts the passage of cold smoke around a closed door.
Third-party certification: Independent ongoing certification of a product or installer by a UKAS-accredited body, beyond a one-off test.
Threshold gap: The gap under a fire door, set by the manufacturer's evidence and sometimes closed with a drop-down seal.
Vision panel: A glazed panel in a door leaf allowing people to see through. In a fire door it must use tested fire-resistant glass.

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