Ajax Fire Alarm vs Intruder Alarm: UK Compliance for Combined Systems
Summary
UK installers can run Ajax fire detection and Ajax intruder detection on the same platform, but the two sides of the system are governed by different British Standards and need different certification paths. Fire detection in a commercial building must be designed, installed, commissioned and maintained to BS 5839-1:2025. Monitored intruder systems that require a Police URN must be installed to PD 6662:2017 with BS 8243:2021 for confirmation, and the product must be EN 50131 Grade 2 or higher. The Ajax EN54 Fire Hub Jeweller (SKU 125732) is the panel that unlocks both worlds — it is EN 54 certified for fire AND supports EN 50131 Grade 2 intrusion on the same Jeweller radio backbone, so one hub can carry both certifications when installed correctly.
This guide walks through how the two standards differ, which Ajax devices belong on which side of the line, and how to specify a combined system that will pass both fire risk assessment and NSI/SSAIB inspection.
Why combined fire and intruder systems are a compliance minefield
A fire alarm and an intruder alarm look superficially similar — wireless sensors, a central panel, a monitoring link — but they are held to completely different standards and are often inspected by different bodies. Mixing them on one panel without understanding that split is the fastest way to produce a system that passes neither.
Fire detection in UK non-domestic premises is governed by BS 5839-1:2025, the code of practice for design, installation, commissioning and maintenance (IET Wiring Matters — Key changes to BS 5839-1:2025, Sep 2025). BS 5839-1:2025 came into effect on 30 April 2025 and replaces the 2017 edition. The product itself must be certified to EN 54, the European product standard for fire detection and fire alarm systems.
Monitored intruder alarms that need a Police URN are governed by PD 6662:2017, the UK application standard that sits over the EN 50131 product series, plus BS 8243:2021 for alarm confirmation (NSI — PD 6662:2017, effective 1 June 2019). The product itself must be certified to EN 50131, typically Grade 2 for a standard commercial site.
Fire sits under fire risk assessment and the Regulatory Reform (Fire Safety) Order 2005. Intruder sits under insurance requirements and, where Police response is required, under the National Police Chiefs' Council policy. The two audit trails almost never overlap.
Which Ajax panel covers which standard
The Ajax range effectively splits into three panel families, and choosing the right one is the single biggest compliance decision on a combined install.
The Ajax Hub 2 Plus (SKU 22925 in white or 22924 in black) is an EN 50131 Grade 2 intruder control panel. It supports up to 200 wireless devices, four communication channels (Ethernet, Wi-Fi and two cellular SIMs) and meets PD 6662:2017 / BS 8243:2021 when configured correctly (Ajax Hub 2 Plus specifications, ajax.systems). It is a pure security panel — it will not drive EN 54 fire detection on its own.
The Ajax EN54 Fire Hub Jeweller (SKU 125732 in white — black variant also stocked) is the EN 54 certified control and indicating equipment (CIE) introduced when Ajax launched its commercial fire line (Ajax press release — EN54 Line for commercial and municipal sites). It carries a 10.1-inch touchscreen, takes up to 200 wireless devices on the Jeweller and Wings radio protocols, and — critically for installers — also supports EN 50131 Grade 2 intrusion, video surveillance and automation on the same platform (EN54 Fire Hub Jeweller product page, ajax.systems). This is the only Ajax panel that can legitimately host both certifications.
The Ajax Hub 2 (2G) and Hub 2 (4G) are single-SIM variants of the Hub 2 family. They are EN 50131 Grade 2 for intruder only, not EN 54 certified, and cannot be used as a fire panel even with Ajax fire sensors paired to them. If a site needs both certifications on one platform, the specification starts at the EN54 Fire Hub Jeweller — there is no downgrade path.
For a legacy intruder-only site being extended with CCTV but no fire work, the Hub 2 Plus remains the installer default. For any new-build or refurb where fire is in scope, the EN54 Fire Hub is the right starting point even if the fire side is phased.
What counts as a fire device and what counts as an intruder device
Every device on the Ajax platform is certified for exactly one of the two worlds, and installers cannot cross the boundary. Putting a domestic-range FireProtect 2 onto a commercial fire install is a BS 5839-1 failure; putting an EN54 FireProtect (Smoke) onto a purely domestic kit is over-engineered and over-priced. The split is explicit in Ajax's product naming — any device in the EN54 sub-range is commercial fire, any device without that prefix is domestic fire or intruder.
On the fire side, the commercial-grade devices for a BS 5839-1 system are the EN54 FireProtect (Smoke/Sounder) Jeweller (SKU 119919), EN54 FireProtect (Heat/Sounder) Jeweller (SKU 119915), the EN54 ManualCallPoint Jeweller in red (SKU 60815) and the EN54 FireProtect (VAD) visual alarm devices. These detectors carry EN 54 certification (Parts 5, 7 and 23 as applicable) and are the only ones that should sit under a commercial fire risk assessment.
On the intruder side, the EN 50131 Grade 2 devices are the MotionProtect U Jeweller PIR (SKU 121295), the DoorProtect U Jeweller opening detector (SKU 121293), the GlassProtect U Jeweller acoustic glass-break detector, the MotionProtect Plus U Jeweller dual-sensor PIR and the Wireless KeyPad TouchScreen arming station (SKU 58455). These will not drive fire evacuation signalling and should never be specced as part of a fire system.
The domestic FireProtect 2 RB (Heat/Smoke/CO) Jeweller (SKU 52252) is a different animal — it is a dual-spectrum optical smoke, heat and CO detector aimed at residential and light commercial use, with a 5-year replaceable-battery life (FireProtect 2 product page, ajax.systems). It pairs with the Hub 2 family and is the right spec for an HMO, a flat conversion or a Part 1 domestic install, but is not EN 54 certified and should not be used in a BS 5839-1 commercial scheme.
How the Ajax platform lets one system do both jobs
The reason combined systems are possible at all on Ajax is the Jeweller and Wings radio protocols, which are the shared wireless backbone for every device family. The EN54 Fire Hub Jeweller uses the same two-way encrypted radio as the Hub 2 Plus, which means fire detectors, intruder sensors, sirens and keypads are all addressable on the same panel under a single account.
Device counts run to 200 wireless endpoints on both the EN54 Fire Hub and the Hub 2 Plus, with a Jeweller radio range of up to 2,000 m line-of-sight — extendable via EN54 Fire ReX Jeweller range extenders (SKU 135975 white, 135976 black) for the fire side or the standard REX 2 Jeweller range extenders for the intruder side. In practice a single commercial site rarely exceeds half the 200-device budget, which leaves plenty of headroom for a staged intruder rollout after the fire install completes.
Management is unified through the Ajax PRO Desktop and Ajax apps. Installers see fire events and intruder events in a single event log, but the two subsystems arm and disarm independently — a fire system must by definition be armed 24/7, while the intruder side follows the customer's schedule. Both can be routed to the same alarm receiving centre over Ajax Cloud, with separate signalling contracts if required.
For a CCTV-led site that already has Hikvision, HiLook or Ruijie gear on network, the Ajax system sits alongside rather than replacing it. There is no native fire/CCTV integration at protocol level, but ARC monitoring, email/SMS events and SIA-IP signalling bridge the two stacks in the ARC rather than on site.
Commissioning and certification: the installer paperwork
A combined Ajax fire + intruder system requires two separate commissioning certificates and typically two different inspection bodies — this is the part installers most often underestimate.
For the fire side, the installer issues a BS 5839-1:2025 Design, Installation and Commissioning Certificate, and most commercial clients will additionally require a third-party certification from a UKAS-accredited scheme such as BAFE SP203-1 or LPCB. The responsible person under the Fire Safety Order is then handed the user manual, zone plans and log book.
For the intruder side, a monitored Grade 2 system requiring Police response needs a PD 6662:2017 certificate of compliance plus a BS 8243:2021 confirmation configuration, and the installer company itself must typically be NSI Gold/Silver or SSAIB approved for the URN to be issued (NSI — Approval schemes). An ARC certified to BS 5979 is the acceptable signalling endpoint.
The Ajax EN54 Fire Hub exposes both certification paths, but it cannot carry them for you — an installer company that is BAFE-approved for fire but not NSI-approved for intruder can only certify half of the system, and vice versa. On larger commercial jobs this is why fire and intruder installs are often tendered separately even when the same panel is in use.
Maintenance is also governed separately: BS 5839-1 calls for at least quarterly fire alarm inspection and annual servicing, while PD 6662 / BS EN 50136 calls for at least annual intruder maintenance with remote monitoring verification. Both intervals should be booked into the client's planned preventative maintenance schedule at handover.
When to pick EN54 Fire Hub vs Hub 2 Plus vs a domestic kit
The specification decision comes down to three questions: is fire detection in scope at all, is the building commercial or domestic, and does the intruder side need Police response? The combinations fall out cleanly into four installer scenarios.
| Site type | Fire in scope? | Police URN needed? | Recommended Ajax panel | Certifications in play |
|---|---|---|---|---|
| Commercial office / retail with full fire cover | Yes (EN 54) | Yes (EN 50131 Grade 2) | EN54 Fire Hub Jeweller | BS 5839-1:2025 + PD 6662:2017 |
| Commercial office, fire only | Yes (EN 54) | No | EN54 Fire Hub Jeweller | BS 5839-1:2025 |
| Commercial office, intruder only with URN | No | Yes (EN 50131 Grade 2) | Hub 2 Plus | PD 6662:2017 + BS 8243:2021 |
| Domestic / HMO with smoke + intruder | Yes (BS 5839-6) | Optional (Grade 2) | Hub 2 Plus + FireProtect 2 | BS 5839-6 + PD 6662:2017 |
| Starter domestic kit | No | No | Ajax Hub 2 Kit 3 | PD 6662:2017 optional |
The most expensive mistake is speccing a Hub 2 Plus on a site that later adds a commercial fire requirement — the Hub 2 Plus cannot be upgraded to EN 54 certification, which means ripping out the panel and replacing it with an EN54 Fire Hub Jeweller if fire is later brought into scope. On any site where commercial fire is even a possibility within 12 months, the EN54 Fire Hub is the future-proof spec.
Signalling, ARC and the Police response question
Police response is an intruder-only concept in UK — fire alarms do not generate a Police URN, they generate a fire brigade call via the ARC if monitored. The two signalling paths are run in parallel but certified separately.
For the intruder side, the Hub 2 Plus and EN54 Fire Hub both signal to the ARC over Ajax Cloud and, on larger sites, directly via SIA-IP. Dual-path signalling is built in (Ethernet + cellular, with Wi-Fi and a second SIM on the Hub 2 Plus), which is what EN 50131-1 Grade 2 ATS 2 expects. The ARC itself must be BS 5979 or equivalent, and the URN is applied for via the local Police force after commissioning.
For the fire side, signalling to the ARC is via Ajax Cloud and, where the client requires L1/L2 BS 5839-1 cover, often bridged to a dedicated fire ARC using the EN54 I/O Module (2X2) Jeweller. Fire signalling is not police-response — it routes to the fire brigade via the ARC under ARC standard BS 5979 and BS EN 50136 for ATS, but the approval trail goes through BAFE / LPCB rather than NSI.
This is why the combined certification bundle is so valuable on commercial sites: a single EN54 Fire Hub replaces what would otherwise be two physically separate panels, two wireless bubbles, and two separate site-survey visits — while still preserving the two independent audit trails both standards demand.
Frequently asked questions
Can I use Ajax FireProtect 2 on a commercial BS 5839-1 fire system?
No. FireProtect 2 is a domestic/residential detector designed for BS 5839-6 category installs and is not EN 54 certified. For a commercial BS 5839-1 fire system, use the Ajax EN54 FireProtect (Smoke/Sounder) Jeweller, EN54 FireProtect (Heat/Sounder) Jeweller, or EN54 FireProtect (Smoke) Jeweller devices paired to the EN54 Fire Hub Jeweller.
Does the EN54 Fire Hub Jeweller replace a Hub 2 Plus?
Yes on a combined commercial site. The EN54 Fire Hub Jeweller is EN 54 certified for fire AND supports EN 50131 Grade 2 intruder, so it functionally covers both certifications on one panel. The Hub 2 Plus remains the right choice for intruder-only sites, domestic installs, or sites where fire is out of scope.
Will Ajax pass Police URN inspection?
Yes when installed by an NSI Gold/Silver or SSAIB approved installer, commissioned to PD 6662:2017 with BS 8243:2021 confirmation, and configured as EN 50131 Grade 2 with two-stage arming and alarm transmission delay set per the standard.
What is the difference between Jeweller and Wings?
Jeweller is the two-way radio protocol used for event transmission between the hub and devices, with an operational range of up to 2 km line-of-sight. Wings is the parallel high-bandwidth radio used for photo verification from the MotionCam range and longer-range fire signalling. The EN54 Fire Hub uses both.
Can I retrofit the EN54 Fire Hub into a site that already has a Hub 2 Plus?
Devices are not transferable between panels — they must be paired to one hub at a time. A retrofit means replacing the Hub 2 Plus and re-pairing every device, or running the EN54 Fire Hub alongside the Hub 2 Plus as a separate system (fire on the new hub, intruder on the old). Most installers elect a clean cutover at the same time as the fire install.
Is the EN54 Fire Hub EN 54-2 and EN 54-4 certified?
Yes — the EN54 Fire Hub Jeweller is certified to EN 54-2 (control and indicating equipment) and EN 54-4 (power supply equipment) as required for a commercial fire panel, along with EN 54-21 for alarm transmission and EN 54-25 for radio links (Ajax EN54 Fire Hub specifications, ajax.systems).
Where Netview can help
Netview stocks the full Ajax EN54 commercial fire range plus the Hub 2 family for intruder, alongside Pyronix, Hikvision AX PRO and the rest of the Ajax wireless portfolio. All Ajax products ship same-day from our Leicester warehouse when ordered before 3pm, and we carry both white and black variants of every mainstream SKU.
Installers starting a combined commercial project can browse the Ajax EN54 Wireless Fire Alarm System range and the Hub 2 Plus intruder panel on the Netview site. For earlier context on the Ajax EN54 line, see our Ajax EN54 Fire Detection installer guide. For deeper technical resources across our other supported platforms — including Hikvision firmware, the Hikvision Tools Hub and the iVMS-4200 installer hub — our Blog Hub pages carry the full technical reference set.
For spec advice on a combined fire + intruder project or a BAFE/NSI-scope tender, call the Netview trade desk on 01163 800 838 or email the team — we can recommend the right Ajax panel for the job, flag compatibility gotchas before you order and ship the same day from stock.
Netview is an authorised UK wholesaler for Hikvision, HiLook and Ruijie, and stocks Ajax, Pyronix, Vigitron, Veracity and Securiflex alongside. All compliance claims in this post are sourced from the cited standards bodies and manufacturer specifications — always verify against the current published standard before certifying a commissioning.
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