Definition
BS 5839
BS 5839 is the British Standard covering the design, installation, commissioning, and maintenance of fire detection and alarm systems in the UK. It is published by the British Standards Institution (BSI) and is divided into multiple parts, each covering specific building types or system components.
BFC Training
Get qualified in this area
EAL Level 3 accredited training — the only nationally recognised qualification across all fire disciplines.
View training courseWhat Does BS 5839 Cover?
BS 5839 is not a single document — it is a family of British Standards that collectively govern fire detection and alarm systems across the full range of UK building types. The most widely referenced part is BS 5839-1, which applies to non-domestic premises such as offices, factories, schools, hotels, and warehouses.
The standard covers the full system lifecycle: initial risk assessment and system categorisation (L1–L5 for life protection, P1–P2 for property protection), engineering design, installation quality, commissioning testing, routine maintenance, and documentation.
Key Parts of BS 5839
The standard is divided into numbered parts:
- Part 1 — Non-domestic premises (offices, schools, factories, hotels)
- Part 3 — Automatic fire alarm systems for the protection of property
- Part 6 — Domestic premises (houses, flats, HMOs, sheltered housing)
- Part 8 — Replacement of fire alarm installations
- Part 9 — Emergency voice communication systems
For most commercial and industrial buildings, Part 1 (BS 5839-1:2017) is the applicable standard. It specifies system categories (L1 to L5 and P1/P2), zone sizing rules (maximum 2,000 m² per zone, one floor per zone), detector spacing, cable requirements, and the competence levels required for installation and maintenance.
Does BS 5839 Have Legal Force?
BS 5839 is a voluntary standard — it is not directly mandated by law. However, it is widely referenced in UK legislation and official guidance, which means compliance is effectively required in practice:
- The Regulatory Reform (Fire Safety) Order 2005 requires fire detection that is "appropriate" for the premises — BS 5839 defines what appropriate means
- Approved Document B references BS 5839 for new-build fire alarm provision
- The Fire and Rescue Service, fire risk assessors, and insurers all use BS 5839 as the benchmark for acceptable standards
- Non-compliance with BS 5839 would be used as evidence of negligence in any enforcement action or prosecution
Who Needs to Comply with BS 5839?
The responsible person for any non-domestic premises has a duty under the RRO to ensure fire detection is adequate. In practice this means engaging a competent fire alarm engineer — typically qualified to the BFC EAL Level 3 standard — to design, install, and maintain a system that meets BS 5839-1.
For domestic premises (including HMOs), Part 6 of BS 5839 applies. Landlords must ensure interlinked smoke and heat alarms are installed in accordance with BS 5839-6 and the Smoke and Carbon Monoxide Alarm (England) Regulations 2022.
When Was BS 5839 Last Updated?
BS 5839-1 was last comprehensively revised in 2017 (BS 5839-1:2017), incorporating changes in detector technology, false alarm management, and competence requirements. BS 5839-6 was updated in 2019. Check the BSI website for the current edition and any amendments before specifying or installing a system.
Relevant UK Standards & Legislation
- BS 5839-1:2017Non-domestic premises — design, installation, commissioning and maintenance
- BS 5839-6:2019Domestic premises — standalone and interlinked alarms and systems
- BS 5839-3Automatic fire alarm systems for the protection of property
- Regulatory Reform (Fire Safety) Order 2005Underpins the legal obligation for fire detection in non-domestic premises
Related Terms
- Addressable Fire Alarm SystemFire Alarm SystemsAn addressable fire alarm system is a type of fire detection network in which every device — including detectors, call points, and sounders — is assigned a unique electronic address, enabling the fire alarm control panel to identify the exact location of an alarm or fault within a building.View definition
- Responsible Person (Fire Safety)Fire Regulations & StandardsThe responsible person is the individual or organisation with control of a non-domestic premises who, under the Regulatory Reform (Fire Safety) Order 2005, has a legal duty to take reasonable steps to reduce the risk of fire, protect occupants, and maintain fire safety measures — including carrying out or commissioning a suitable fire risk assessment.View definition
- Emergency Response StandardFire Regulations & StandardsAn Emergency Response Standard is a risk-based target that sets the required response time and minimum number of firefighting staff to attend emergency incidents. Each UK fire and rescue service sets its own standards based on local risk assessment and publishes them in its Integrated Risk Management Plan.View definition
- Fire Safety ProtectionFire Regulations & StandardsFire safety protection is the activity undertaken by fire and rescue services to advise, inspect, and enforce fire safety standards in regulated premises, primarily under the Regulatory Reform (Fire Safety) Order 2005. Protection officers audit premises, issue enforcement notices, and prosecute non-compliant duty holders.View definition
Frequently Asked Questions
BS 5839 is the British Standard covering the design, installation, commissioning, and maintenance of fire detection and alarm systems in the UK. It is published by the British Standards Institution (BSI) and is divided into multiple parts, each covering specific building types or system components.
Requirements for bs 5839 in the UK depend on the type of premises and applicable legislation, including the Regulatory Reform (Fire Safety) Order 2005 and relevant British Standards. The responsible person for a premises must ensure adequate fire safety provisions are in place. The British Fire Consortium can provide guidance — contact our team or search our member directory to find a qualified specialist.
BS 5839 and Addressable Fire Alarm System are related fire safety concepts but serve different purposes. See our individual glossary entries for detailed definitions. For expert guidance on which applies to your premises, consult a BFC member company.
The British Fire Consortium offers EAL Level 3 accredited training covering fire safety systems including topics related to bs 5839. Our courses are the only nationally recognised Level 3 qualifications across all fire disciplines. View our training courses or use the member directory to find a qualified trainer near you.