Gas Suppression Systems

A gas suppression system extinguishes a fire by displacing or absorbing oxygen and heat with a clean agent: no water, no residue, no clean-up. They’re used wherever water-based suppression would do more damage than the fire itself: data centres, comms rooms, switchgear rooms, archives, museum stores, MRI rooms and laboratories. If your asset register includes equipment that can’t be replaced overnight or data that can’t be re-keyed, gas is the right answer.

Inert gas (e.g. ProInert IG-55, Inergen IG-541) is a blend of naturally-occurring gases (argon, nitrogen, CO₂) that reduces oxygen below the combustion threshold while remaining breathable. Larger cylinder banks, slower discharge, environmentally neutral. Chemical agents (FM-200 / HFC-227ea, Novec 1230) are synthetic clean agents stored as a liquid that vaporise on discharge, absorbing heat and interrupting the combustion reaction. Smaller cylinder count, faster discharge (typically 10 seconds), but higher global-warming potential (FM-200) or premium cost (Novec 1230). Choice depends on room volume, environmental policy and budget.

A site survey establishes room volume, integrity, ventilation, occupancy and existing detection. From the survey we model agent quantity to BS EN 15004 (gaseous extinguishing systems) and BS 6535-2 (clean-agent selection), specify the cylinder room, draft pipework and nozzles, and integrate the detection and release control. Typical timelines: small single-zone install 2–3 weeks on site; mid multi-zone 4–6 weeks; large data centres phased over maintenance windows. Design and procurement add 4–6 weeks before site work begins.

Indicative ranges from real UK commercial jobs: small single-zone server room £15k–£25k; mid multi-zone data centre £40k–£80k; large data centre with redundant agents and full integrity reporting £80k–£200k+. Drivers: room volume (the single biggest factor), agent choice, enclosure integrity, integration scope with the existing fire alarm and BMS, access difficulty, and commissioning depth. Annual integrity testing and servicing typically from £1,800 per zone. Your site survey produces a fixed quote.

Properly designed systems are designed for human-occupiable spaces at their design concentration. Inert systems reduce oxygen to a level that no longer supports combustion but remains breathable; Inergen specifically contains a small CO₂ component that stimulates deeper breathing during discharge. Chemical agents at design concentration are safe for occupants. All systems include a pre-discharge alarm with an evacuation period so the room can be vacated before agent release.

Yes, we integrate with every major fire alarm platform (Apollo, Hochiki, Advanced, Gent Vigilon, Honeywell). The fire alarm provides cross-zoned detection; the suppression release control sits alongside it on its own listed-and-approved release panel, with the cause-and-effect engineered to require confirmation from two independent detectors before discharge. That prevents accidental discharge from a single false alarm.

BS EN 15004 / BS ISO 14520 require an annual service: cylinder weight check, agent batch verification, detection circuit verification and discharge-release proving. Hose pressure tests are typically every 5 years. Room integrity testing (often called the “door fan test”) should be done at install, then every 5 years or after any alteration that might affect room sealing: cable penetrations, new ductwork, removed walls. Servicing contracts from £1,800 per zone per year.

Yes. We run a free transition audit when we take over an existing system: compliance gap analysis, asset register reconciliation, and a one-off catch-up service if anything has slipped through the previous contractor. Our maintenance contracts have no long lock-in (90 days’ notice) and no hidden recharge clauses. Whatever your incumbent has on the system, we’ll service it: we’re cross-trained on every major manufacturer.