Data centres are the backbone of the digital economy. This guide covers VESDA detection, clean agent suppression, lithium-ion battery risks, and emergency planning for mission-critical facilities.. Protecting Digital Infrastructure The UK data centre market is worth over £4.5 billion annually, with more than 450 facilities processing the data that powers modern society. A single fire incident can cause billions in economic damage, data loss, and service disruption affecting millions of users. Unique Fire Risks High Density Electrical Equipment Server racks generating 20 40 kW per rack in high performance computing Power distribution units carrying thousands of amps Cable density — tens of thousands of cables in risers and trays Arc flash — potential for electrical arcing in switchgear Battery Storage (UPS) Lithium ion batteries — thermal runaway risk, toxic gas production VRLA batteries — hydrogen off gassing, electrolyte leakage Energy density — modern UPS rooms contain megawatt hours of stored energy Charging cycles — increased failure risk during charge/discharge transitions Cooling Systems Refrigerants — some classified as combustible (R 32, R 454B) Hot aisle containment — trapping heat that could accelerate fire development Water cooling — liquid cooled servers creating electrical short circuit risks Free cooling — bringing external contaminants into the facility Detection Strategy VESDA (Very Early Smoke Detection Apparatus) Aspirating detection sampling air continuously from the protected space Sensitivity : detecting smoke at 0.005% obscuration/metre Response time : typically 30 90 seconds faster than point detectors Sampling : network of pipes with calibrated holes in ceiling void and server aisles Multi level alarm : Alert → Action → Fire stages allowing graduated response Supplementary Detection In rack smoke detectors — point detectors within individual rack enclosures Thermal imaging cameras — real time hot spot monitoring in server rooms Gas detection — hydrogen sensors in battery rooms, refrigerant leak detection Power monitoring — anomaly detection in electrical consumption patterns Suppression Systems System Agent Suitable For Residue Ozone Impact FK 5 1 12 (Novec 1230) Fluoroketone Server rooms None Zero IG 541 (Inergen) N₂/Ar/CO₂ blend Server rooms None Zero IG 55 (Argonite) N₂/Ar blend Server rooms None Zero Water mist Fine water spray Cable tunnels Minimal None Pre action sprinkler Water Low risk areas Significant None Clean Agent Design Considerations Room integrity — door fan test to BS EN 15004, <50% loss in 10 minutes Agent concentration — minimum 5.3% for Novec 1230, held for 10+ minutes Discharge time — maximum 10 seconds from activation to design concentration Hold time — minimum 10 minutes at design concentration Personnel safety — NOAEL limits, pre discharge alarm, time delay Emergency Response 1. Automated response — detection → suppression → HVAC shutdown → notification (all within 30 seconds) 2. Remote monitoring — 24/7 NOC (Network Operations Centre) with fire alarm integration 3. Fire service liaison — pre incident plans with local fire crews 4. Business continuity — automatic failover to redundant facility 5. Post incident — clean agent removal, air quality testing, equipment inspection before restart Tier Classification Impact on Fire Safety Tier Uptime Fire Safety Requirement I 99.671% Basic detection + portable extinguishers II 99.741% VESDA + clean agent, single path III 99.982% Redundant detection + suppression, dual path IV 99.995% Fully redundant, fault tolerant, 2N suppression Lithium Ion Battery Room Protection The growing use of lithium ion UPS introduces specific fire risks: Thermal runaway detection — multi spectrum IR sensors monitoring cell temperatures Gas detection — electrolyte vapour and hydrogen fluoride monitoring Ventilation — dedicated mechanical extraction for battery rooms Separation — fire rated enclosure with minimum REI 120 Suppression — water based systems (clean agents ineffective on lithium fires) Blast relief — venting panels for vapour cloud ignition scenarios Magnus Opifex SEVEN LTD — UK's Leading Fire Safety & Fire Engineering Consultancy 🌐 magnus opifex.co.uk 📞 +44 7486 691724 ✉️ office@magnus opifex.co.uk Founders: Nicoleta Vasile, Baroness of Brattleby — CEO, Lawyer and Barrister, Legal & Administrative Director Alina — Technical Director & Expert Fire Engineer (BEng) Head Office: Ealing Cross, 85 Uxbridge Road, London W5 5BW Magnus Opifex SEVEN LTD delivers engineering led fire engineering, fire risk assessments, CFD modelling, and building safety consultancy across the United Kingdom and internationally. With over 20 years of combined experience and a UK portfolio spanning healthcare, residential and infrastructure, we bring truly engineered solutions with a personal touch. © 2026 Magnus Opifex SEVEN LTD. All rights reserved.