Frequently Asked Questions

The category depends on your building's use, occupancy, and fire risk assessment. Category L systems protect life — ranging from L1 (full coverage) through to L5 (site-specific). Category P systems protect property. Category M is manual-only (call points without automatic detection). Your fire risk assessment should specify the required category. If you don't have a fire risk assessment, you'll need one carried out by a qualified fire risk assessor before a system can be designed. We can point you in the right direction if you need help finding one.

L1 provides automatic detection throughout all areas of the building. L2 covers defined areas beyond escape routes (typically high-risk rooms). L3 covers escape routes only — corridors, stairways, and landings. L4 covers escape routes within residential accommodation only. L5 is a bespoke category designed for a specific fire engineering solution. The right category comes from your fire risk assessment. Read our full guide to fire alarm categories.

P1 provides automatic detection throughout the building for property protection, while P2 covers only defined areas of high fire risk. P2 is more common in commercial premises where specific high-value or high-risk areas need protecting.

BS 5839-1 requires a minimum of six-monthly servicing by a competent person. This is also a requirement under the Regulatory Reform (Fire Safety) Order 2005. Some premises with higher risk profiles may benefit from quarterly inspections. Between professional visits, the responsible person should carry out weekly alarm tests.

Almost all commercial premises require some form of fire detection and alarm system. The Regulatory Reform (Fire Safety) Order 2005 places a duty on the responsible person to ensure adequate fire detection and warning. The type and extent of the system is determined by your fire risk assessment.

BS 5839-1 is the British Standard code of practice for the design, installation, commissioning, and maintenance of fire detection and fire alarm systems in non-domestic premises. It sets out the requirements for system categories, device spacing, cable types, testing procedures, and documentation. All our work is carried out to this standard.

It depends entirely on the size and complexity of the premises. A small office might take a day or two, while a large multi-building site could take a year or more. We can provide a programme of works so you know what to expect and can plan around any disruption.

Yes — we routinely install fire alarm systems in occupied buildings. We plan the work around your operations, carrying out noisy or disruptive tasks outside business hours where needed. For schools, we schedule major works during holidays wherever possible.

Conventional systems identify which zone has activated but not the specific device. Addressable systems identify the exact device, giving you pinpoint location information at the panel. Addressable systems are generally more suitable for larger buildings and offer better false alarm management through device sensitivity adjustment.

Yes. Wireless fire alarm systems are particularly useful for listed buildings, historic properties, and premises where running cables would be impractical or damaging. We specify wireless systems from leading manufacturers that meet the same BS 5839-1 requirements as wired systems. We also install hybrid systems, where only part of the building uses wireless — useful when most of the site is wired but one area is difficult or impractical to cable.

Our engineers test every device on the system — detectors, call points, sounders, and interfaces. They check the panel for faults, inspect batteries, verify cause and effect programming, and test the system's response. All results are logged digitally using NimbusGO for full audit traceability. You receive a complete service report after each visit.

Frequent false alarms usually indicate a problem that needs investigating — dirty detectors, incorrect detector type for the environment, or a system fault. Don't be tempted to isolate devices, as this leaves you unprotected. Contact us and we'll diagnose the issue and recommend a solution, whether that's cleaning, relocating, or changing detector types.

Absolutely. We maintain fire alarm systems from all manufacturers, regardless of who installed them. We'll carry out an initial survey to assess the system's condition and familiarise ourselves with the installation before taking over the maintenance contract.

Installation is the physical fitting of cables, devices, and panels. Commissioning is the systematic testing and verification process that proves the installed system works correctly and meets its design specification. Commissioning is a separate discipline — we can commission systems installed by others, and some clients bring us in specifically for independent commissioning. Learn more about commissioning.

An Emergency Voice Communication System (EVCS) provides two-way communication between firefighters and building occupants during an evacuation. Any multi-storey building with disabled refuge areas needs EVCS so that people waiting in a refuge can communicate with the building's control point. It's also required in buildings with firefighting shafts, buildings above 18m, sports stadia, and other complex buildings. EVCS is covered by BS 5839-9. We design, install, and commission EVCS — it's one of our specialist areas. Learn more about EVCS.

Yes. We install intrinsically safe (IS) fire detection in environments where flammable gases, vapours, or dusts may be present — such as fuel stores, spray booths, and similar hazardous areas. IS detection uses ATEX-rated devices and barriers to ensure the detection circuit cannot generate enough energy to ignite the surrounding atmosphere. If your fire risk assessment identifies a hazardous zone, we can specify and install the right IS detection for your environment.

You receive a Certificate of Conformity for design, installation, verification, and commissioning — as specified in BS 5839-1. You also receive as-fitted drawings showing all device locations, cable routes, and system zoning, plus an Operation and Maintenance manual and system logbook.