Fire safety glossary
Plain English definitions of the terms used in UK fire safety law, British Standards and building safety, from Accountable Person to zone plan.
A
- Accountable Person
- Anyone who owns, or has a legal obligation to repair, the common parts of a higher-risk building in England under the Building Safety Act 2022. Read the guide
- Addressable fire alarm
- A fire alarm system in which every detector and call point has its own address, so the panel shows exactly which device has operated. Read the guide
- Alarm receiving centre (ARC)
- A monitoring centre that receives signals from a fire alarm panel and passes them on to the fire and rescue service or a keyholder.
- AOV
- Automatic opening vent. A window or vent that opens automatically to release smoke from a stair or corridor when smoke is detected.
B
- BAFE
- The British Approvals for Fire Equipment, which runs third-party certification schemes for fire safety companies, such as SP203-1 for fire alarms and SP205 for fire risk assessment.
- BS 5266-1
- The British Standard code of practice for emergency lighting. Read the guide
- BS 5839-1
- The British Standard code of practice for fire detection and alarm systems in non-domestic premises. The current edition was published in 2025. Read the guide
- BS 5839-6
- The British Standard code of practice for fire detection and alarm systems in domestic premises, including HMOs. Read the guide
- BS 8629
- The British Standard for evacuation alert systems used by the fire and rescue service in residential buildings. Read the guide
- Building Safety Regulator (BSR)
- The regulator set up under the Building Safety Act 2022 to oversee the safety of higher-risk buildings in England. Read the guide
C
- Call point
- A manual device, usually a red box with a frangible element, that anyone can operate to raise the fire alarm.
- Cause and effect
- The programmed actions a fire alarm takes when a device operates, such as sounding alarms, releasing door holders, recalling lifts or opening vents.
- Cavity barrier
- A fire-resisting barrier inside a cavity, such as behind cladding or above a ceiling, that stops fire and smoke spreading through the void. Read the guide
- Compartmentation
- The division of a building into fire-resisting compartments so that a fire is contained in the area where it starts. Read the guide
- Conventional fire alarm
- A fire alarm system that groups devices into zones, showing which zone is in alarm but not which device. Read the guide
E
- EICR
- Electrical Installation Condition Report. A periodic inspection and test of a fixed electrical installation against BS 7671. Read the guide
- Emergency lighting
- Lighting that comes on automatically when the normal supply fails, so people can find their way out safely. Read the guide
- EWS1 form
- A form used by valuers and lenders to record that the external wall of a residential building has been assessed for fire safety. Read the guide
F
- FD30S
- A fire door rated to resist fire for 30 minutes, with smoke seals to restrict cold smoke. Read the guide
- Fire risk assessment (FRA)
- A structured review of the fire hazards in a building, the people at risk and the measures needed to keep them safe. Read the guide
- Fire Safety Act 2021
- Legislation confirming that the Fire Safety Order covers the structure, external walls and flat entrance doors of buildings with two or more sets of domestic premises. Read the guide
- Fire Safety Order
- The Regulatory Reform (Fire Safety) Order 2005, the main fire safety law for non-domestic premises in England and Wales. Read the guide
- Fire stopping
- Sealing gaps and service penetrations through fire-resisting walls and floors with tested products, to keep compartmentation intact. Read the guide
- FRAEW
- Fire risk appraisal of external walls, carried out to PAS 9980 to assess the fire risk of cladding and wall construction. Read the guide
G
- Golden thread
- The accurate, up-to-date digital record of a higher-risk building's safety information required by the Building Safety Act 2022. Read the guide
- Grade D1
- A BS 5839-6 domestic alarm grade: mains-powered alarms with a tamper-proof standby battery. Read the guide
H
- Higher-risk building (HRB)
- In occupation, a building in England at least 18 metres tall or with at least seven storeys, with at least two residential units. Read the guide
- HMO
- House in multiple occupation: a property let to three or more people from more than one household who share facilities. Read the guide
I
- Intumescent strip
- A strip fitted in a fire door or frame that expands when heated to seal the gap around the door. Read the guide
K
- Key building information
- Information about a higher-risk building's structure, materials and safety systems that must be submitted to the Building Safety Regulator. Read the guide
L
- L1 to L5
- The life protection categories of fire alarm under BS 5839-1, from L1 (detection throughout) to L5 (a bespoke system for a specific risk). Read the guide
- LD2
- A BS 5839-6 domestic alarm category: detection in escape routes and in rooms that pose a high fire risk, such as the living room and kitchen. Read the guide
M
- Mandatory occurrence reporting
- The duty on Accountable Persons to report safety occurrences that could cause significant harm in a higher-risk building to the Building Safety Regulator. Read the guide
- Multi-sensor detector
- A detector that combines smoke and heat sensing to reduce false alarms while still responding quickly to a real fire. Read the guide
P
- PAS 79
- The code of practice for fire risk assessment, with Part 1 for non-domestic premises and Part 2 for housing. Read the guide
- PAS 9980
- The code of practice for fire risk appraisal of external wall construction and cladding of multi-storey residential buildings. Read the guide
- Principal Accountable Person (PAP)
- The Accountable Person responsible for the structure and exterior of a higher-risk building, who leads on registration and the safety case report. Read the guide
R
- Responsible Person
- The person with duties under fire safety law for a building, usually the employer, owner or whoever controls the premises. Read the guide
S
- Safety case report
- A document prepared by the Principal Accountable Person summarising the building safety risks of a higher-risk building and how they are managed. Read the guide
- Single Building Assessment
- Scotland's approach to assessing fire risk in residential buildings with external wall concerns, looking at the whole building. Read the guide
- Stay put
- An evacuation strategy for blocks of flats in which residents not affected by a fire stay in their own flat, relying on compartmentation. Read the guide
W
- Waking watch
- Trained people patrolling a building to detect fire and raise the alarm, usually as a temporary measure while defects are fixed. Read the guide
Z
- Zone plan
- A diagram displayed next to a fire alarm panel showing the building's alarm zones, so a fire can be located quickly. Read the guide
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